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Castellvi Corrons X, Gummel J, Smets J, Berti D. Liquid-liquid phase separated microdomains of an amphiphilic graft copolymer in a surfactant-rich medium. J Colloid Interface Sci 2022; 615:807-820. [PMID: 35180629 DOI: 10.1016/j.jcis.2022.02.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/29/2022] [Accepted: 02/06/2022] [Indexed: 11/28/2022]
Abstract
The liquid-liquid phase separation (LLPS) of amphiphilic thermoresponsive copolymers can lead to the formation of micron-sized domains, known as simple coacervates. Due to their potential to confine active principles, these copolymer-rich droplets have gained interest as encapsulating agents. Understanding and controlling the conditions inducing this LLPS is therefore essential for applicative purposes and requires thorough fundamental studies on self-coacervation. In this work, we investigate the LLPS of a comb-like graft copolymer (PEG-g-PVAc) consisting of a poly(ethylene glycol) backbone (6 kDa) with ∼2-3 grafted poly(vinyl acetate) chains, and a PEG/PVAc weight ratio of 40/60. Specifically, we report the effect of various water-soluble additives on its phase separation behavior. Kosmotropes and non-ionic surfactants were found to decrease the phase separation temperature of the copolymer, while chaotropes and, above all, ionic surfactants increased it. We then focus on the phase behavior of PEG-g-PVAc in the presence of sodium citrate and a C14-15 E7 non-ionic surfactant (N45-7), defining the compositional range for the generation of LLPS microdomains at room temperature and monitoring their formation with fluorescence confocal microscopy. Finally, we determine the composition of the microdomains through confocal Raman microscopy, demonstrating the presence of PEG-g-PVAc, N45-7, and water. These results expand our knowledge on polymeric self-coacervation, clarifying the optimal conditions and composition needed to obtain LLPS microdomains with encapsulation potential at room temperature in surfactant-rich formulations.
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Affiliation(s)
- Xavier Castellvi Corrons
- Department of Chemistry "Ugo Schiff" University of Florence, CSGI, Via della Lastruccia 3, 50019 Sesto Fiorentino Florence, Italy
| | - Jeremie Gummel
- Strategic Innovation and Technology, Procter & Gamble Brussels Innovation Center, Temselaan 100, 1853 Grimbergen, Belgium
| | - Johan Smets
- Strategic Innovation and Technology, Procter & Gamble Brussels Innovation Center, Temselaan 100, 1853 Grimbergen, Belgium
| | - Debora Berti
- Department of Chemistry "Ugo Schiff" University of Florence, CSGI, Via della Lastruccia 3, 50019 Sesto Fiorentino Florence, Italy
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Granatto CF, Grosseli GM, Sakamoto IK, Fadini PS, Varesche MBA. Influence of cosubstrate and hydraulic retention time on the removal of drugs and hygiene products in sanitary sewage in an anaerobic Expanded Granular Sludge Bed reactor. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 299:113532. [PMID: 34614559 DOI: 10.1016/j.jenvman.2021.113532] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/24/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Diclofenac (DCF), ibuprofen (IBU), propranolol (PRO), triclosan (TCS) and linear alkylbenzene sulfonate (LAS) can be recalcitrant in Wastewater Treatment Plants (WWTP). The removal of these compounds was investigated in scale-up (69 L) Expanded Granular Sludge Bed (EGSB) reactor, fed with sanitary sewage from the São Carlos-SP (Brazil) WWTP and 200 mg L-1 of ethanol. The EGSB was operated in three phases: (I) hydraulic retention time (HRT) of 36±4 h; (II) HRT of 20±2 h and (III) HRT of 20±2 h with ethanol. Phases I and II showed no significant difference in the removal of LAS (63 ± 11-65 ± 12 %), DCF (37 ± 18-35 ± 11 %), IBU (43 ± 18-44 ± 16 %) and PRO (46 ± 25-51 ± 23 %) for 13±2-15 ± 2 mg L-1, 106 ± 32-462 ± 294 μg L-1, 166 ± 55-462 ± 213 μg L-1 and 201 ± 113-250 ± 141 μg L-1 influent, respectively. Higher TCS removal was obtained in phase I (72 ± 17 % for 127 ± 120 μg L-1 influent) when compared to phase II (51 ± 13 % for 135 ± 119 μg L-1 influent). This was due to its greater adsorption (40 %) in the initial phase. Phase III had higher removal of DCF (42 ± 10 % for 107 ± 26 μg L-1 influent), IBU (50 ± 15 % for 164 ± 47 μg L-1 influent) and TCS (85 ± 15 % for 185 ± 148 μg L-1 influent) and lower removal of LAS (35 ± 14 % for 12 ± 3 mg L-1 influent) and PRO (-142 ± 177 % for 188 ± 88 μg L-1 influent). Bacteria similar to Syntrophobacter, Smithella, Macellibacteroides, Syntrophus, Blvii28_wastewater-sludge_group and Bacteroides were identified in phase I with relative abundance of 3.1 %-4.7 %. Syntrophobacter was more abundant (15.4 %) in phase II, while in phase III, it was Smithella (12.7 %) and Caldisericum (15.1 %). Regarding the Archaea Domain, Methanosaeta was more abundant in phases I (84 %) and II (67 %), while in phase III it was Methanobacterium (86 %).
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Affiliation(s)
- Caroline F Granatto
- Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Ave Trabalhador São-Carlense, No. 400, Zipcode 13566-590, São Carlos, SP, Brazil.
| | - Guilherme M Grosseli
- Federal University of São Carlos, Washington LuizHighway, Km 235, Zipcode 13565-905, São Carlos, SP, Brazil.
| | - Isabel K Sakamoto
- Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Ave Trabalhador São-Carlense, No. 400, Zipcode 13566-590, São Carlos, SP, Brazil.
| | - Pedro S Fadini
- Federal University of São Carlos, Washington LuizHighway, Km 235, Zipcode 13565-905, São Carlos, SP, Brazil.
| | - Maria Bernadete A Varesche
- Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Ave Trabalhador São-Carlense, No. 400, Zipcode 13566-590, São Carlos, SP, Brazil.
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3
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Ribeiro C, Scheufele FB, Alves HJ, Kroumov AD, Espinoza-Quiñones FR, Módenes AN, Borba CE. Evaluation of hybrid neutralization/biosorption process for zinc ions removal from automotive battery effluent by dolomite and fish scales. ENVIRONMENTAL TECHNOLOGY 2019; 40:2373-2388. [PMID: 29448890 DOI: 10.1080/09593330.2018.1441332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 02/11/2018] [Indexed: 06/08/2023]
Abstract
This work focused in the evaluation of Oreochromis niloticus fish scales (FS) as biosorbent material in the removal of Zn from a synthetic effluent based on automotive battery industry effluent and, further, a hybrid neutralization/biosorption process, aiming at a high-quality treated effluent, by a cooperative use of dolomite and FS. For this, a physicochemical and morphological characterization (i.e. SEM-EDX, FTIR, XRD, and TXRF) was performed, which helped to clarify a great heterogeneity of active sites (phosphate, carbonate, amide, and hydroxyl) on the biosorbent; also the inorganic constituents (apatites) leaching from the FS was identified. Biosorption results pointed out to a pH-dependent process due to changes in the functional group's anionic character (i.e. electrostatic interactions), where an initial pH = 3 favored the Zn uptake. Kinetic and equilibrium studies confirmed the heterogeneous surface and cooperative sorption, wherein experimental data were described by Generalized Elovich kinetic model and the favorable isotherm profile by Langmuir-Freundlich isotherm ( qmax = 15.38 mg g-1 and 1/n>1 ). Speciation diagram of Zn species along with the leached species demonstrated that, for the studied pH range, the biosorption was the most likely phenomena rather than precipitation. Finally, the hybrid neutralization/biosorption process showed great potential since both the Zn concentration levels and the pH reached the legislation standards (CZn = 4 mg L-1; pH = 5). Hence, based on the characterization and biosorption results, a comprehensive evaluation of the involved mechanisms in such complex system helped to verify the prospective of FS biosorbent for the Zn treatment from solution, in both individual and hybrid processes.
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Affiliation(s)
- C Ribeiro
- a Department of Chemical Engineering - Post graduate Program, West Parana State University - UNIOESTE , Toledo , Brazil
| | - F B Scheufele
- b Department of Engineering and Exact Sciences, Federal University of Paraná , Palotina , Brazil
| | - H J Alves
- b Department of Engineering and Exact Sciences, Federal University of Paraná , Palotina , Brazil
| | - A D Kroumov
- c Department of Applied Microbiology, Division 'Microbial Synthesis and Ecology' The 'Stephan Angeloff' Institute of Microbiology - Bulgarian Academy of Sciences , Sofia , Bulgaria
| | - F R Espinoza-Quiñones
- a Department of Chemical Engineering - Post graduate Program, West Parana State University - UNIOESTE , Toledo , Brazil
| | - A N Módenes
- a Department of Chemical Engineering - Post graduate Program, West Parana State University - UNIOESTE , Toledo , Brazil
| | - C E Borba
- a Department of Chemical Engineering - Post graduate Program, West Parana State University - UNIOESTE , Toledo , Brazil
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de Santana da Silva J, Heck MC, Buzo MG, Almeida IV, Vicentini VEP. Evaluation of textile laundry effluents and their cytotoxic effects on Allium cepa. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:27890-27898. [PMID: 30056543 DOI: 10.1007/s11356-018-2813-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 07/20/2018] [Indexed: 06/08/2023]
Abstract
Industrial laundries have water as one of their main inputs and they release effluents in large amounts, with a high polluting load, which are usually discarded into the environment, or they are insufficiently treated for release into the neighboring water bodies. The aim of this study was to evaluate the efficiencies of the biological treatments in an industrial textile laundry and their environmental impact on the surface waters of the stream where the dump is usually made, by using cytotoxicity tests on the meristematic root cells of Allium cepa L. The results have shown, for the most part, that the treated effluents over a period of 24 h showed reductions in their mitotic index. The treatments on the raw effluents showed cytotoxic effects when compared to control, with cell division recoveries after 24 h in the waters. Cytotoxic effects were additionally observed in the stream waters, at a point before the dump, indicating that they received a pollutant load, before the effluent disposal site of the evaluated industrial laundry. Notably, the treatments that were being applied by the industrial laundry were effective throughout the processing, reducing the concentrations of the toxic substances. When considering the data presented, it is now understood that there is a constant need for the evaluation of industrial effluents, as well as for the waters of the streams and the rivers that receive these disposals, in order to preserve and maintain the quality of the waters, the organisms, and consequently, the ecosystems.
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Affiliation(s)
- Jaqueline de Santana da Silva
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Avenida Colombo, 5.790, Bloco H67, Sala 11, Jardim Universitário, Maringá, Paraná, 87020-900, Brazil
| | - Michele Cristina Heck
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Avenida Colombo, 5.790, Bloco H67, Sala 11, Jardim Universitário, Maringá, Paraná, 87020-900, Brazil
| | - Matheus Gimenez Buzo
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Avenida Colombo, 5.790, Bloco H67, Sala 11, Jardim Universitário, Maringá, Paraná, 87020-900, Brazil
| | - Igor Vivian Almeida
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Avenida Colombo, 5.790, Bloco H67, Sala 11, Jardim Universitário, Maringá, Paraná, 87020-900, Brazil.
| | - Veronica Elisa Pimenta Vicentini
- Department of Biotechnology, Genetics and Cell Biology, State University of Maringá, Avenida Colombo, 5.790, Bloco H67, Sala 11, Jardim Universitário, Maringá, Paraná, 87020-900, Brazil
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Guan R, Yuan X, Wu Z, Wang H, Jiang L, Li Y, Zeng G. Functionality of surfactants in waste-activated sludge treatment: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 609:1433-1442. [PMID: 28800686 DOI: 10.1016/j.scitotenv.2017.07.189] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 07/21/2017] [Accepted: 07/21/2017] [Indexed: 06/07/2023]
Abstract
Proper treatment of waste-activated sludge (WAS) involves three pivotal processes, dewatering, anaerobic digestion, and pollutants removal, which need to be re-assessed urgently. Although many traditional sludge treatments have been developed, it is prudent to enhance the efficiency of sludge treatment using multifunctional, flexible, and environmentally friendly surfactants. With regard to sludge dewatering, surfactants can weaken the binding interaction between sludge flocs and promote the dissolution of extracellular polymeric substances (EPSs), resulting in the release of bound water. Using surfactants in anaerobic digestion promotes the release of enzymes trapped in sludge and improves the activity of enzymes during hydrolysis. Owing to their characteristic encapsulation of hydrophobes into self-assembled aggregates (micelles), surfactants can form host-guest complexes with polycyclic aromatic hydrocarbons (PAHs). Additionally, surfactants can enhance the desorption of heavy metals and prevent the emergence of heavy metal residue. This review summarizes the current surfactant-based sludge treatment technologies according to their roles in sludge disposal solutions. Then, possible mechanisms of surfactants in sludge dewatering, anaerobic digestion, and the removal of organic pollutants and heavy metals are analysed systemically. Finally, changes to sludge treatment via the aid of surfactants are highlighted. This review presents the comprehensive advances in the use of surfactants in WAS reduction, recycling, and risk relief, underscoring their roles in increasing economic efficiency and ensuring environmental quality.
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Affiliation(s)
- Renpeng Guan
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Xingzhong Yuan
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
| | - Zhibin Wu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Hou Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China; School of Chemical & Biomedical Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Longbo Jiang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Yifu Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environment Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China
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6
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Garcia MT, Ribosa I, Perez L, Manresa A, Comelles F. Micellization and Antimicrobial Properties of Surface-Active Ionic Liquids Containing Cleavable Carbonate Linkages. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:6511-6520. [PMID: 28605906 DOI: 10.1021/acs.langmuir.7b00505] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Imidazolium-based ionic liquids (ILs) containing cleavable carbonate linkages, 1-alkyloxycarbonyloxyethyl-3-methylimidazolium chlorides with alkyl chains of 10, 12, and 14 carbon atoms, were synthesized, and their self-assembly behavior and antimicrobial activity were investigated. Differential scanning calorimetry and polarized optical microscopy studies reveal that carbonate-functionalized ILs form stable thermotropic smectic liquid-crystalline phases over a wide range of temperature. The surface activity and aggregation behavior of these new ILs were investigated by tensiometry, conductometry, potentiometry, and spectrofluorimetry. The size of aggregates was examined by dynamic light scattering (DLS). Carbonate-functionalized ILs display a higher adsorption efficiency and a lower critical micelle concentration (cmc) than simple alkyl-chain-substituted ILs. The insertion of a carbonate ester moiety in the alkyl side chain favors adsorption at the air-water interface and micellization in the bulk solution when compared to nonfunctionalized ILs. DLS measurements show that small micellelike aggregates are spontaneously formed above the cmc. Furthermore, carbonate-functionalized ILs were examined for their antimicrobial activity against a panel of clinically relevant microorganisms. Biological activity was found to increase with hydrophobicity. The presence of a carbonate ester moiety significantly enhances the antimicrobial efficiency as compared to nonfunctionalized ILs, with the susceptibility of Staphylococcus sp. toward the action of these compounds being particularly remarkable. It has been demonstrated that the functionalization of the alkyl side chain of the imidazolium salts can not only modify the aggregation behavior but also lead to differences in both efficiency and the spectrum of antimicrobial activity of amphiphilic ILs.
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Affiliation(s)
- M Teresa Garcia
- Department of Chemical and Surfactants Technology, Institute of Advanced Chemistry of Catalonia IQAC- CSIC , Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Isabel Ribosa
- Department of Chemical and Surfactants Technology, Institute of Advanced Chemistry of Catalonia IQAC- CSIC , Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Lourdes Perez
- Department of Chemical and Surfactants Technology, Institute of Advanced Chemistry of Catalonia IQAC- CSIC , Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Angeles Manresa
- Facultat de Farmacia, Universitat de Barcelona , Joan XXIII, 08028 Barcelona, Spain
| | - Francesc Comelles
- Department of Chemical and Surfactants Technology, Institute of Advanced Chemistry of Catalonia IQAC- CSIC , Jordi Girona 18-26, 08034 Barcelona, Spain
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Ríos F, Lechuga M, Fernández-Serrano M, Fernández-Arteaga A. Aerobic biodegradation of amphoteric amine-oxide-based surfactants: Effect of molecular structure, initial surfactant concentration and pH. CHEMOSPHERE 2017; 171:324-331. [PMID: 28027477 DOI: 10.1016/j.chemosphere.2016.12.070] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 12/08/2016] [Accepted: 12/15/2016] [Indexed: 06/06/2023]
Abstract
The present study was designed to provide information regarding the effect of the molecular structure of amphoteric amine-oxide-based surfactants and the initial surfactant concentration on their ultimate biodegradation. Moreover, given this parameter's pH-dependence, the effect of pH was also investigated. Three amine-oxide-based surfactants with structural differences in their hydrophobic alkyl chain were tested: Lauramine oxide (AO-R12), Myristamine oxide (AO-R14) and Cocamidopropylamine oxide (AO-Cocoamido). We studied the ultimate biodegradation using the Modified OECD Screening Test at initial surfactant concentrations ranged from 5 to 75 mg L-1 and at pH levels from 5 to 7.4. The results demonstrate that at pH 7.4, amine-oxide-based surfactants are readily biodegradable. In this study, we concluded that ω-oxidation can be assumed to be the main biodegradation pathway of amine-oxides and that differences in the biodegradability between them can be explained by the presence of an amide group in the alkyl chain of AO-Cocoamido; the CN fission of the amide group slows down their mineralization process. In addition, the increase in the concentration of the surfactant from 5 to 75 mg L-1 resulted in an increase in the final biodegradation of AO-R12 and AO-R14. However, in the case of AO-Cocoamido, a clear relationship between the concentration and biodegradation cannot be stated. Conversely, the biodegradability of AO-R12 and AO-R14 was considerably lower in an acid condition than at a pH of 7.4, whereas AO-Cocoamido reached similar percentages in acid conditions and at a neutral pH. However, microorganisms required more time to acclimate.
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Affiliation(s)
- Francisco Ríos
- Department of Chemical Engineering, Faculty of Science, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain.
| | - Manuela Lechuga
- Department of Chemical Engineering, Faculty of Science, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Mercedes Fernández-Serrano
- Department of Chemical Engineering, Faculty of Science, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Alejandro Fernández-Arteaga
- Department of Chemical Engineering, Faculty of Science, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
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Ríos F, Fernández-Arteaga A, Lechuga M, Jurado E, Fernández-Serrano M. Kinetic study of the anaerobic biodegradation of alkyl polyglucosides and the influence of their structural parameters. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:8286-8293. [PMID: 26820643 DOI: 10.1007/s11356-016-6129-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
This paper reports a study of the anaerobic biodegradation of non-ionic surfactants alkyl polyglucosides applying the method by measurement of the biogas production in digested sludge. Three alkyl polyglucosides with different length alkyl chain and degree of polymerization of the glucose units were tested. The influence of their structural parameters was evaluated, and the characteristics parameters of the anaerobic biodegradation were determined. Results show that alkyl polyglucosides, at the standard initial concentration of 100 mgC L(-1), are not completely biodegradable in anaerobic conditions because they inhibit the biogas production. The alkyl polyglucoside having the shortest alkyl chain showed the fastest biodegradability and reached the higher percentage of final mineralization. The anaerobic process was well adjusted to a pseudo first-order equation using the carbon produced as gas during the test; also, kinetics parameters and a global rate constant for all the involved metabolic process were determined. This modeling is helpful to evaluate the biodegradation or the persistence of alkyl polyglucosides under anaerobic conditions in the environment and in the wastewater treatment.
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Affiliation(s)
- Francisco Ríos
- Department of Chemical Engineering, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Alejandro Fernández-Arteaga
- Department of Chemical Engineering, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain.
| | - Manuela Lechuga
- Department of Chemical Engineering, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Encarnación Jurado
- Department of Chemical Engineering, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Mercedes Fernández-Serrano
- Department of Chemical Engineering, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
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Gotoh K, Horibe K, Mei Y, Tsujisaka T. Effects of Water Hardness on Textile Detergency Performance in Aqueous Cleaning Systems. J Oleo Sci 2016; 65:123-33. [PMID: 26782305 DOI: 10.5650/jos.ess15168] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effects of water hardness on textile detergency in aqueous solutions were systematically investigated using four surfactants: sodium oleate (OLNa), linear dodecylbenzene sulfonate (LAS), sodium dodecyl sulfate (AS), and polyoxyethylene (10) dodecyl ether (AE). Water hardness was adjusted according to the standard procedure described in IEC 60734:2012. As expected, by adding hardness salts the surface tension of the OLNa solution increased. Surprisingly, the addition of hardness salts lowers the surface tension for the LAS and AS solutions. In the case of the AE solution, hardness salt did not affect the surface tension. A decrease in transmittance and foamability after adding hardness salts was observed for every anionic surfactant solution, indicating that anionic surfactants can combine with divalent ions to form insoluble precipitates. Detergency experiments were performed using cotton plain-woven and towel fabrics soiled with a carbon black and oleic acid mixture. One piece each of untreated and soiled fabric were stacked and placed horizontally in detergent solution with or without hardness salts. As a mechanical action of soil removal, the shaking of 190 spm was applied. Soil removal and redeposition due to washing were evaluated from changes in values of the Kubelka-Munk function for both fabrics. With increasing water hardness, soil removal decreased and redeposition increased. In order of decreasing detergency, the surfactants were as follows: LAS > OLNa ≈ AS > AE. The results indicate that precipitates, formed by reaction of LAS or AS with hardness salts, are strongly adsorbed on the water surface because of their hydrophobicity, but they have no detergency power. The field emission scanning electron microscopic observation and X-ray photoelectron spectroscopic analysis showed that Ca(LAS)2 precipitation clung to fiber surfaces, and remained on the surfaces after washing. Significant changes in the cotton fabric due to washing were observed in mechanical properties and water absorbency.
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Affiliation(s)
- Keiko Gotoh
- Faculty of Human Life and Environment, Nara Women's University
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γ-H2AX induced by linear alkylbenzene sulfonates is due to deoxyribonuclease-1 translocation to the nucleus via actin disruption. Mutat Res 2015; 777:33-42. [PMID: 25938903 DOI: 10.1016/j.mrfmmm.2015.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 04/02/2015] [Accepted: 04/07/2015] [Indexed: 12/25/2022]
Abstract
Phosphorylation of histone H2AX (γ-H2AX) occurs following formation of DNA double strand breaks (DSBs). Other types of DNA damage also generate DSBs through DNA replication and repair, leading to the production of γ-H2AX. In the present study, we demonstrated that linear alkylbenzene sulfonates (LAS), the most widely used and non-genotoxic anionic surfactants, could generate γ-H2AX via a novel pathway. Breast adenocarcinoma MCF-7 cells were treated with five kinds of LAS with alkyl chains ranging from 10 to 14 carbon units (C10-C14LAS). The generation of DSBs and subsequent production of γ-H2AX increased in a manner that depended on the number of carbon units in LAS. γ-H2AX could also be generated with non-cytotoxic doses of LAS and was independent of the cell cycle, indicating the non-apoptotic and DNA replication-independent formation of DSBs. The generation of γ-H2AX could be attenuated by EGTA and ZnCl2, deoxyribonuclease-1 (DNase I) inhibitors, as well as by the knockdown of DNase I. LAS weakened the interaction between DNase I and actin, and the enhanced release of DNase I was dependent on the number of carbon units in LAS. DNase I released by the LAS treatment translocated to the nucleus, in which DNase I attacked DNA and generated γ-H2AX. These results suggested that the LAS-induced generation of γ-H2AX could be attributed to the translocation of DNase I to the nucleus through the disruption of actin, and not to LAS-induced DNA damage.
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Netskina OV, Tayban ES, Moiseenko AP, Komova OV, Mukha SA, Simagina VI. Removal of 1,2-dichlorobenzene from water emulsion using adsorbent catalysts and its regeneration. JOURNAL OF HAZARDOUS MATERIALS 2015; 285:84-93. [PMID: 25497020 DOI: 10.1016/j.jhazmat.2014.10.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 09/27/2014] [Accepted: 10/04/2014] [Indexed: 06/04/2023]
Abstract
Purification of emulsions of 1,2-dichlorobenzene (1,2-DCB) by carbon-based adsorbent catalysts has been studied. The cycle of purification includes: (1) adsorption of 1,2-DCB from the aqueous phase and (II) reductive regeneration by hydrodechlorination of the adsorbed 1,2-DCB by molecular hydrogen in the liquid phase. 1,2-DCB adsorption from aqueous solutions has been found to proceed by the mechanism of volume filling of pores. The rate of hydrodechlorination was shown to correlate with the particle size of the active component: the finer the particles, the higher the activity of the adsorbent catalyst. Pd/FAS with an average Pd particle size of 2.8 nm was found to be the most efficient catalyst.
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Affiliation(s)
- O V Netskina
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia.
| | - E S Tayban
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - A P Moiseenko
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia; Department of Chemistry and Chemical Technology, Novosibirsk State Technical University, Pr. Karla Marksa 20, Novosibirsk 630092, Russia
| | - O V Komova
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - S A Mukha
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - V I Simagina
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia; Siberian Branch of the Russian Presidential Academy of National Economy and Public Administration, Nizhegorodskaya 6, Novosibirsk 630102, Russia
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12
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Self-assembly and antimicrobial activity of long-chain amide-functionalized ionic liquids in aqueous solution. Colloids Surf B Biointerfaces 2014; 123:318-25. [DOI: 10.1016/j.colsurfb.2014.09.033] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 09/04/2014] [Accepted: 09/15/2014] [Indexed: 11/20/2022]
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13
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Okada DY, Esteves AS, Delforno TP, Hirasawa JS, Duarte ICS, Varesche MBA. Influence of co-substrates in the anaerobic degradation of an anionic surfactant. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2013. [DOI: 10.1590/s0104-66322013000300008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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García MT, Campos E, Sánchez-Leal J, Comelles F. Structure-Activity Relationships for Sorption of Alkyl Trimethyl Ammonium Compounds on Activated Sludge. TENSIDE SURFACT DET 2013. [DOI: 10.3139/113.100229] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Association of quaternary ammonium based surfactants with activated sludge from wastewater treatment plants has been studied. Adsorption isotherms on activated sludge particles and surface properties of a series of alkyl trimethyl ammonium compounds have been investigated. The effect of alkyl chain length and the water hardness in those physical-chemical properties have been evaluated. Adsorption on sludge increased with increasing the alkyl chain length in the cationic surfactant molecule. Linear relationships between critical micelle concentration (-log CMC) and efficiency of adsorption at the liquid/gas interface (pC20), and the number of carbon atoms in the alkyl chain length were found for the alkyl trimethyl ammonium compounds. Water hardness decreased the CMC values of the tested alkyl trimethyl ammonium homologues and the extent of their sorption to activated sludge. Langmuir and Freundlich adsorption isotherms described satisfactorily the equilibrium adsorption of the cationic surfactants on activated sludge.
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15
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Okbah MA, Ibrahim AMA, Gamal MNM. Environmental monitoring of linear alkylbenzene sulfonates and physicochemical characteristics of seawater in El-Mex Bay (Alexandria, Egypt). ENVIRONMENTAL MONITORING AND ASSESSMENT 2013; 185:3103-15. [PMID: 22851193 PMCID: PMC3586065 DOI: 10.1007/s10661-012-2776-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2011] [Accepted: 07/05/2012] [Indexed: 05/12/2023]
Abstract
In the present work, the influence of different physicochemical characteristics on the distribution of anionic detergents, linear alkylbenzene sulfonates (LAS), was studied. Surface and bottom water samples were collected from eight different sites from a small bay near the main sewage discharge of Alexandria City (El-Max Bay). The results showed great variations in the concentrations, as a function of the regional and seasonal variations. The study revealed that the pH values lie in the normal side, with a range of 8.0-8.5 inside the bay and 7.5-7.7 at El-Umum Drain effluent. Wide variations, observed between the surface and the bottom water of the bay, salinity, dissolved oxygen, oxidizable organic matter, total hardness, and total alkalinity, were scattered in the ranges (3.33-42.73 practical salinity unit), (0.42-8.27 mg O2/l), (0.12-10.49 mg/l), (1.39-8.99 mg/l), and (0.23-0.48 mg/l), respectively. The regional variations of LAS concentrations in the bay waters showed that the concentration decreased as the distance from the source of drainage water (El-Umum Drain). The seasonal average variations of LAS cleared out that summer and spring periods had the highest concentrations at surface (0.13 ± 0.04 mg LAS/l) and bottom (0.12 ± 0.10 mg LAS/l) layer, which is attributed to increase in population density and human activities. The inverse relationships between total LAS concentration and salinity, dissolved oxygen, and calcium ions concentration are r = -0.78, 0.50, and 0.67, respectively. This is related to the occurrence of the untreated wastewater containing detergents, the biodegradation rate of surfactants, and strong precipitation of LAS as Ca.
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Affiliation(s)
- M A Okbah
- National Institute of Oceanography and Fisheries, Alexandria, Egypt.
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16
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Garcia MT, Ribosa I, Perez L, Manresa A, Comelles F. Aggregation behavior and antimicrobial activity of ester-functionalized imidazolium- and pyridinium-based ionic liquids in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:2536-45. [PMID: 23360222 DOI: 10.1021/la304752e] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Two series of long chain imidazolium- and pyridinium-based ionic liquids containing an ester functional group in the alkyl side chain, 3-methyl-1-alkyloxycarbonylmethylimidazolium bromides (C(n)EMeImBr) and 1-alkyloxycarbonylmethylpyridinium bromides (C(n)EPyrBr), were synthesized and their thermal stability, aggregation behavior in aqueous medium, and antimicrobial activity investigated. The introduction of an ester group decreased the thermal stability of the functionalized ILs compared to simple alkyl chain containing ILs (1-alkyl-3-methylimidazolium bromides and 1-alkylpyridinium bromides). Tensiometry, conductimetry, and spectrofluorimetry were applied to study the self-aggregation of the amphiphilic ILs in aqueous solution. The ILs investigated displayed surface activity and the characteristic chain length dependence of the micellization process of surfactants. As compared to simple alkyl chain containing ILs bearing the same hydrocarbon chain, ester-functionalized ILs possess higher adsorption efficiency (pC(20)) and significantly lower critical micelle concentration (cmc) and surface tension at the cmc (γ(cmc)), indicating that the incorporation of an ester group promotes adsorption at the air/water interface and micelle formation. The antimicrobial activity was evaluated against Gram-negative and Gram-positive bacteria and fungi. ILs containing more than eight carbon atoms in the alkyl chain showed antimicrobial activity. Their efficiency as antimicrobial agents increased with the hydrophobicity of the amphiphilic cation being the C(12) homologous the most active compounds. The incorporation of an ester group particularly increased the biological activity against fungi.
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Affiliation(s)
- M Teresa Garcia
- Department of Chemical and Surfactant Technology, Institut de Quimica Avançada de Catalunya IQAC-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
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17
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Renaud F, Oberhänsli F, Teyssié JL, Miramand P, Temara A, Warnau M. Sorption-desorption kinetics and toxic cell concentration in marine phytoplankton microalgae exposed to Linear Alkylbenzene Sulfonate. MARINE POLLUTION BULLETIN 2011; 62:942-947. [PMID: 21435668 DOI: 10.1016/j.marpolbul.2011.02.051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 02/18/2011] [Accepted: 02/24/2011] [Indexed: 05/30/2023]
Abstract
Linear Alkylbenzene Sulfonates (LAS) are ubiquitous surfactants. Traces can be found in coastal environments. Sorption and toxicity of C(12)-LAS congeners were studied in controlled conditions (2-3500 μg C(12)LAS/L) in five marine phytoplanktonic species, using standardized methods. IC(50) values ranged from 0.5 to 2 mg LAS/L. Sorption of (14)C(12)-6 LAS isomer was measured at environmentally relevant trace levels (4μg/L) using liquid scintillation counting. Steady-state sorption on algae was reached within 5h in the order dinoflagellate>diatoms>green algae. The sorption data, fitted a L-type Freundlich isotherm, indicating saturation. Desorption was rapid but a low LAS fraction was still sorbed after 24h. Toxic cell concentration was 0.38±0.09 mg/g for the studied species. LAS toxicity results from sorption on biological membranes leading to non-specific disturbance of algal growth. Results indicate that LAS concentrations in coastal environments do not represent a risk for these organisms.
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Affiliation(s)
- Florent Renaud
- International Atomic Energy Agency-Marine Environment Laboratories (IAEA-MEL), 4 Quai Antoine 1er, MC-98000 Principality of Monaco, Monaco, France.
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18
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Moldovan Z, Avram V, Marincas O, Petrov P, Ternes T. The determination of the linear alkylbenzene sulfonate isomers in water samples by gas-chromatography/mass spectrometry. J Chromatogr A 2010; 1218:343-9. [PMID: 21159344 DOI: 10.1016/j.chroma.2010.11.043] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 10/17/2010] [Accepted: 11/22/2010] [Indexed: 10/18/2022]
Abstract
A number of 20 compounds of linear alkylbenzene sulfonates (LASs) family were identified by electron impact mass spectrometry (EI-MS) in water samples collected from wastewater treatment plants (WWTP). This paper presents the mass spectra of 20 compounds, the proposed mechanism of formation of the diagnostic ions obtained by EI-MS and the distribution of individual isomers in water samples collected from compartments of WWTP. The individual isomers from four homolog series C(10)-, C(11)-, C(12)- and C(13)-LAS were analyzed as methyl derivatives.
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Affiliation(s)
- Zaharie Moldovan
- National Institute of Research and Development for Isotopic and Molecular Technology (INCDTIM), Donath Street 65-103, 400293 Cluj-Napoca, Romania.
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19
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Cornellas A, Perez L, Comelles F, Ribosa I, Manresa A, Garcia MT. Self-aggregation and antimicrobial activity of imidazolium and pyridinium based ionic liquids in aqueous solution. J Colloid Interface Sci 2010; 355:164-71. [PMID: 21186035 DOI: 10.1016/j.jcis.2010.11.063] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 11/18/2010] [Accepted: 11/20/2010] [Indexed: 11/18/2022]
Abstract
Two series of long-chain imidazolium and pyridinium based ionic liquids (1-alkyl-3-methylimidazolium and 1-alkylpyridinium bromides) were synthesised and the effect of the alkyl chain length and the nature of the cationic head group on micellization and antimicrobial activity of the ionic liquids (ILs) were investigated. Tensiometry, conductometry, spectrofluorimetry and PGSE-NMR were applied to study the self-aggregation of the amphiphilic ILs in aqueous solution. The ILs investigated displayed surface activity and the characteristic chain length dependence of the micellization process of surfactants. The antimicrobial activity was evaluated against Gram-negative and Gram-positive bacteria and fungi. ILs containing more than eight carbon atoms in the alkyl chain showed antimicrobial activity. Their efficiency as antimicrobial agents increased with the hydrophobicity of the amphiphilic cation being the C(14) homologous the most active compounds.
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Affiliation(s)
- Anna Cornellas
- Department of Chemical and Surfactant Technology, Institut de Quimica Avançada de Catalunya (IQAC), CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
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20
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Rico-Rico A, Droge STJ, Hermens JLM. Predicting sediment sorption coefficients for linear alkylbenzenesulfonate congeners from polyacrylate-water partition coefficients at different salinities. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:941-947. [PMID: 20058863 DOI: 10.1021/es902453s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The effect of the molecular structure and the salinity on the sorption of the anionic surfactant linear alkylbenzenesulfonate (LAS) to marine sediment has been studied. The analysis of several individual LAS congeners in seawater and of one specific LAS congener at different dilutions of seawater was carried out after extraction by polyacrylate solid-phase microextraction (SPME) fibers. Sorption isotherms for the tested LAS congeners on marine sediment and at different ionic composition were all nonlinear with a constant Freundlich exponent (n(F)) of 0.78 +/- 0.05. Differences in LAS sorption of a number of congeners were similar to the differences among the linear partition coefficients (K(fw)) observed for the polyacrylate SPME fibers in seawater. The sorption of LAS to both the sediment and the SPME fiber significantly decreased in media with lower salinity. Dissolved calcium could fully account for the changed affinity of LAS for the SPME fiber, although the high sorption in seawater was also equaled by a corresponding dissolved concentration of NaCl only. Sediment sorption coefficients of a single LAS congener at varying ionic composition was not as strongly related to the K(fw) values as the relation observed for different LAS compounds in seawater, likely because sorption mechanisms are different in both phases. In the absence of experimental data for octanol-water coefficients (K(ow)) of (i) individual LAS congeners at (ii) different ionic compositions, the use of K(fw) as a tool to predict sorption and other hydrophobicity-related processes is suggested.
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Affiliation(s)
- Angeles Rico-Rico
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
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21
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Coll C, Martínez-Máñez R, Marcos MD, Sancenón F, Soto J, Mahajan RK. Efficient Removal of Anionic Surfactants Using Mesoporous Functionalised Hybrid Materials. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900391] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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Samper E, Rodríguez M, De la Rubia M, Prats D. Removal of metal ions at low concentration by micellar-enhanced ultrafiltration (MEUF) using sodium dodecyl sulfate (SDS) and linear alkylbenzene sulfonate (LAS). Sep Purif Technol 2009. [DOI: 10.1016/j.seppur.2008.11.013] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Hampel M, Canário J, Branco V, Vale C, Blasco J. Environmental levels of Linear alkylbenzene Sulfonates (LAS) in sediments from the Tagus estuary (Portugal): environmental implications. ENVIRONMENTAL MONITORING AND ASSESSMENT 2009; 149:151-161. [PMID: 18228153 DOI: 10.1007/s10661-008-0190-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 01/14/2008] [Indexed: 05/25/2023]
Abstract
Sediments from the Tagus estuary (Portugal) were collected at 40 stations in July and December 2004. Total LAS concentrations ranged between 0.03 and 17.76 mg LAS.kg(-1) dry weight in July, and between 0.09 and 9.57 mg LAS.kg(-1) in December. Highest LAS concentrations were found at the upper northern part of the estuary, coincident with the localisation of an important waste water treatment station. According to the Predicted No Effect Concentration (PNEC) of 8.1 mg.kg(-1) derived for this compound, Environmental Risk Assessment (ERA) identified a hazard for the ecosystem at the station with the highest LAS concentration, and similar results are obtained by Equilibrium Partitioning Method (EPM). Nevertheless, LAS concentrations decreased significantly between samplings in the stations with the highest LAS concentrations in July, whereas increased LAS concentrations at adjacent stations were found in December. In the remaining stations, LAS concentrations were up to three orders of magnitude lower, representing no hazard for the sediment community.
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Affiliation(s)
- M Hampel
- Institute of Aquaculture, University of Stirling, Stirling, UK.
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24
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Wang P, Keller AA. Partitioning of hydrophobic pesticides within a soil-water-anionic surfactant system. WATER RESEARCH 2009; 43:706-714. [PMID: 19026434 DOI: 10.1016/j.watres.2008.10.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 10/23/2008] [Accepted: 10/30/2008] [Indexed: 05/27/2023]
Abstract
Surfactants can be added to pesticide-contaminated soils to enhance the treatment efficiency of soil washing. Our results showed that pesticide (atrazine and diuron) partitioning and desorbability within a soil-water-anionic surfactant system is soil particle-size dependent and is significantly influenced by the presence of anionic surfactant. Anionic surfactant (linear alkylbenzene sulphonate, LAS) sorption was influenced by its complexation with both the soluble and exchangeable divalent cations in soils (e.g. Ca2+, Mg2+). In this study, we propose a new concept: soil system hardness which defines the total amount of soluble and exchangeable divalent cations associated with a soil. Our results showed that anionic surfactant works better with soils having lower soil system hardness. It was also found that the hydrophobic organic compounds (HOCs) sorbed onto the LAS-divalent cation precipitate, resulting in a significant decrease in the aqueous concentration of HOC. Our results showed that the effect of exchangeable cations and sorption of HOC onto the surfactant precipitates needs to be considered to accurately predict HOC behavior within soil-water-anionic surfactant systems.
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Affiliation(s)
- Peng Wang
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106, USA
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25
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Probabilistic risk assessment for linear alkylbenzene sulfonate (LAS) in sewage sludge used on agricultural soil. Regul Toxicol Pharmacol 2007; 49:245-59. [DOI: 10.1016/j.yrtph.2007.09.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Revised: 09/06/2007] [Accepted: 09/06/2007] [Indexed: 11/20/2022]
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26
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Jensen J, Smith SR, Krogh PH, Versteeg DJ, Temara A. European risk assessment of LAS in agricultural soil revisited: species sensitivity distribution and risk estimates. CHEMOSPHERE 2007; 69:880-92. [PMID: 17765285 DOI: 10.1016/j.chemosphere.2007.07.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 06/13/2007] [Accepted: 07/15/2007] [Indexed: 05/17/2023]
Abstract
Linear alkylbenzene sulphonate (LAS) is used at a rate of approximately 430,000 tons/y in Western Europe, mainly in laundry detergents. It is present in sewage sludge (70-5,600 mg/kg; 5-95th percentile) because of its high usage per capita, its sorption and precipitation in primary settlers, and its lack of degradation in anaerobic digesters. Immediately after amendment, calculated and measured concentrations are <1 to 60 mg LAS/kg soil. LAS biodegrades rapidly in soil with primary and ultimate half-lives of up to 7 and 30 days, respectively. Calculated residual concentrations after the averaging time (30 days) are 0.24-18 mg LAS/kg soil. The long-term ecotoxicity to soil microbiota is relatively low (EC10 >or=26 mg sludge-associated LAS/kg soil). An extensive review of the invertebrate and plant ecotoxicological data, combined with a probabilistic assessment approach, led to a PNEC value of 35 mg LAS/kg soil, i.e. the 5th percentile (HC5) of the species sensitivity distribution (lognormal distribution of the EC10 and NOEC values). Risk ratios were identified to fall within a range of 0.01 (median LAS concentration in sludge) to 0.1 (95th percentile) and always below 0.5 (maximum LAS concentration measured in sludge) according to various scenarios covering different factors such as local sewage influent concentration, water hardness, and sewage sludge stabilisation process. Based on the present information, it can be concluded that LAS does not represent an ecological risk in Western Europe when applied via normal sludge amendment to agricultural soil.
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Affiliation(s)
- John Jensen
- Department of Terrestrial Ecology, National Environmental Research Institute, Ministry of the Environment, P.O. Box 314, Vejlsøvej 25, DK-8600 Silkeborg, Denmark.
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Schouten N, van der Ham LGJ, Euverink GJW, de Haan AB. Selection and evaluation of adsorbents for the removal of anionic surfactants from laundry rinsing water. WATER RESEARCH 2007; 41:4233-41. [PMID: 17614119 DOI: 10.1016/j.watres.2007.05.044] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 05/22/2007] [Accepted: 05/29/2007] [Indexed: 05/06/2023]
Abstract
Low-cost adsorbents were tested to remove anionic surfactants from laundry rinsing water to allow re-use of water. Adsorbents were selected corresponding to the different surfactant adsorption mechanisms. Equilibrium adsorption studies of linear alkyl benzene sulfonate (LAS) show that ionic interaction results in a high maximum adsorption capacity on positively charged adsorbents of 0.6-1.7 gLAS/g. Non-ionic interactions, such as hydrophobic interactions of LAS with non-ionic resins or activated carbons, result in a lower adsorption capacity of 0.02-0.6 gLAS/g. Negatively charged materials, such as cation exchange resins or bentonite clay, have negligible adsorption capacities for LAS. Similar results are obtained for alpha olefin sulfonate (AOS). Cost comparison of different adsorbents shows that an inorganic anion exchange material (layered double hydroxide) and activated carbons are the most cost-effective materials in terms of the amount of surfactant adsorbed per dollar worth of adsorbent.
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Affiliation(s)
- Natasja Schouten
- Wetsus, Centre for Sustainable Water Technology, Agora 1, PO Box 1113, 8900 CC Leeuwarden, The Netherlands.
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Duarte ICS, Oliveira LL, Saavedra NKD, Fantinatti-Garboggini F, Oliveira VM, Varesche MBA. Evaluation of the microbial diversity in a horizontal-flow anaerobic immobilized biomass reactor treating linear alkylbenzene sulfonate. Biodegradation 2007; 19:375-85. [PMID: 17647084 DOI: 10.1007/s10532-007-9143-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2006] [Accepted: 07/02/2007] [Indexed: 10/23/2022]
Abstract
The purpose of this work was to assess the degradation of linear alkylbenzene sulfonate (LAS) in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor. The reactor was filled with polyurethane foam where the sludge from a sanitary sewage treatment was immobilized. The hydraulic detention time (HDT) used in the experiments was of 12 h. The reactor was fed with synthetic substrate (410 mg l(-1) of meat extract, 115 mg l(-1) of starch, 80 mg l(-1) of saccharose, 320 mg l(-1) of sodium bicarbonate and 5 ml l(-1) of salt solution) in the following stages of operation: SI-synthetic substrate, SII-synthetic substrate with 7 mg l(-1) of LAS, SIII-synthetic substrate with 14 mg l(-1) of LAS and SIV-synthetic substrate containing yeast extract (substituting meat extract) and 14 mg l(-1) of LAS, without starch. At the end of the experiment (313 days) a degradation of approximately 35% of LAS was achieved. The higher the concentration of LAS, the greater the amount of foam for its adsorption. This is necessary because the isotherm of LAS adsorption in the foam is linear for the studied concentrations (2 to 50 mg l(-1)). Microscopic analyses of the biofilm revealed diverse microbial morphologies, while Denaturing Gradient Gel Eletrophoresis (DGGE) profiling showed variations in the population of total bacteria and sulphate-reducing bacteria (SRB). The 16S rRNA gene sequencing and phylogenetic analyses revealed that the members of the order Clostridiales were the major components of the bacterial community in the last reactor operation step.
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Affiliation(s)
- I C S Duarte
- Department of Hydraulics and Sanitation, School of Engineering of São Carlos, University of São Paulo, Brazil. Av. Trabalhador São-Carlense, no. 400, São Carlos, SP 13566-590, Brazil.
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29
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Kannan N, White SM, Whelan MJ. Predicting diffuse-source transfers of surfactants to surface waters using SWAT. CHEMOSPHERE 2007; 66:1336-45. [PMID: 16908048 DOI: 10.1016/j.chemosphere.2006.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Revised: 06/14/2006] [Accepted: 07/03/2006] [Indexed: 05/11/2023]
Abstract
Chemicals present in domestic wastewater can adsorb to solid phase materials during sewage treatment. If biosolids (or sewage sludge) are applied to land, these chemicals can be transferred to soil. Under some circumstances they can also be transferred to surface waters during storm events either in solution or attached to sediment. In this paper we describe the utility of the SWAT 2000 model to estimate diffuse-source surface water exposure to "down-the-drain" chemicals. The model was applied hypothetically to predict the behaviour of linear alkylbenzene sulphonate (LAS), an anionic surfactant commonly used in household detergents, in a small catchment in Bedfordshire, UK, where it has previously been successfully validated for stream flow, sediments and pesticides. LAS transfers were estimated for two scenarios: (1) realistic and (2) reasonable worst case, based on assumptions on sludge application rates and the concentration of LAS in sludge. In addition, the sensitivity of the model output to the proportion of the catchment to which sludge is applied was established. Soil wetness and the total quantity of biosolids applied were the biggest determinants of chemical transport from the catchment. The potential of SWAT as a higher-tier tool in environmental risk assessments is discussed.
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Affiliation(s)
- N Kannan
- Texas A&M University, Blackland Research and Extension Centre, 720, East Blackland Road, Temple, TX 76502, USA.
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Perales JA, Manzano MA, Garrido MC, Sales D, Quiroga JM. Molecular structure and biodegradation kinetics of linear alkylbenzene sulphonates in sea water. Biodegradation 2006; 18:567-78. [PMID: 17149657 DOI: 10.1007/s10532-006-9088-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2006] [Accepted: 10/26/2006] [Indexed: 10/23/2022]
Abstract
The present paper describes the results of the application of the biodegradation test proposed by the United States Environmental Protection Agency (USEPA) "Biodegradability in sea water" Office of Prevention, Pesticides, and Toxic Substances (OPPTS) 835.3160, to Linear Alkylbenzene Sulphonate (LAS), the synthetic surfactant with the highest consumption volume on a world-wide basis. High performance liquid chromatography (HPLC) has been employed for the separation and quantification of the different homologues and isomers of the surfactant. Water from the Bay of Cádiz (South-West of the Iberian peninsula) has been used as test medium. The results indicate how both lag and t (50) time shows a significant linear relationship with the length of the alkyl chain of the homologue; the effect of this is that the homologues of longer chain length not only begin to degrade first but also degrade at a faster rate. Regarding the isomeric composition, it is observed that as the percentage of biodegradation increases, there is an increase in the proportion of internal isomers, in comparison with the isomeric relationships of the original test substance.
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Affiliation(s)
- Jose A Perales
- Area of Environmental Technologies, Faculty of Marine and Environmental Sciences, University of Cadiz, Campus de Puerto Real, 11500 Puerto Real, Cadiz, Spain.
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Garcia MT, Campos E, Sánchez-Leal J, Ribosa I. Effect of linear alkylbenzene sulphonates (LAS) on the anaerobic digestion of sewage sludge. WATER RESEARCH 2006; 40:2958-64. [PMID: 16844184 DOI: 10.1016/j.watres.2006.05.033] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 05/11/2006] [Accepted: 05/18/2006] [Indexed: 05/10/2023]
Abstract
Batch anaerobic biodegradation tests with different alkylbenzene sulphonates (LAS) at increasing concentrations were performed in order to investigate the effect of LAS homologues on the anaerobic digestion process of sewage sludge. Addition of LAS homologues to the anaerobic digesters increased the biogas production at surfactant concentrations 5-10 g/kg dry sludge and gave rise to a partial or total inhibition of the methanogenic activity at higher surfactant loads. Therefore, at the usual LAS concentration range in sewage sludge, no adverse effects on the anaerobic digesters functioning of a wastewater treatment plant (WWTP) can be expected. The increase of biogas production at low surfactant concentrations was attributed to an increase of the bioavailability and subsequent biodegradation of organic pollutants associated with the sludge, promoted by the surfactant adsorption at the solid/liquid interface. When the available surfactant fraction in the aqueous phase instead of the nominal surfactant concentration was used to evaluate the toxicity of LAS homologues, a highly significant relationship between toxicity and alkyl chain length was obtained. Taking into account the homologue distribution of commercial LAS in the liquid phase of the anaerobic digesters of a WWTP, an EC(50) value of 14 mg/L can be considered for LAS toxicity on the anaerobic microorganisms.
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Affiliation(s)
- M T Garcia
- Department of Surfactant Technology, IIQAB-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
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Teresa García M, Campos E, Sánchez‐Leal J, Comelles F. Sorption of Alkyl Benzyl Dimethyl Ammonium Compounds by Activated Sludge. J DISPER SCI TECHNOL 2006. [DOI: 10.1080/01932690600662554] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Prats D, López C, Vallejo D, Varó P, León VM. Effect of temperature on the biodegradation of linear alkylbenzene sulfonate and alcohol ethoxylate. J SURFACTANTS DETERG 2006. [DOI: 10.1007/s11743-006-0377-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Garcia MT, Campos E, Dalmau M, Illán P, Sánchez-Leal J. Inhibition of Biogas Production by Alkyl Benzene Sulfonates (LAS) in a Screening Test for Anaerobic Biodegradability. Biodegradation 2006; 17:39-46. [PMID: 16453170 DOI: 10.1007/s10532-005-2798-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2005] [Indexed: 10/25/2022]
Abstract
The effect of the inoculum source on the digestion of linear alkylbenzene sulfonates (LAS) under anaerobic conditions has been investigated. The potential for primary and ultimate LAS biodegradation of anaerobic sludge samples obtained from wastewater treatment plants (WWTPs) of different geographical locations was studied applying a batch test system. It was found that only 4-22% of the LAS added to the batch anaerobic digesters was primarily transformed suggesting a poor primary degradation of the LAS molecule in anaerobic discontinuous systems. Regarding ultimate biodegradation, the addition of LAS to the batch anaerobic digesters caused a reduction on the extent of biogas production. Significant differences in the inhibition extent of the biogas production were observed (4-26%) depending on the sludge used as inoculum. Effect of the surfactant on the anaerobic microorganisms was correlated with its concentration in the aqueous phase. Sorption of LAS on anaerobic sludge affects its toxicity by depletion of the available fraction of the surfactant. LAS content on sludge was related to the total amount of calcium and magnesium extractable ions. The presence of divalent cations promote the association of LAS with anaerobic sludge reducing its bioavailability and the extent of its inhibitory effect on the biogas production.
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Affiliation(s)
- M Teresa Garcia
- Department of Surfactant Technology, IIQAB/CSIC, Barcelona, Spain.
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Conrad A, Cadoret A, Corteel P, Leroy P, Block JC. Adsorption/desorption of linear alkylbenzenesulfonate (LAS) and azoproteins by/from activated sludge flocs. CHEMOSPHERE 2006; 62:53-60. [PMID: 15950257 DOI: 10.1016/j.chemosphere.2005.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2004] [Revised: 03/22/2005] [Accepted: 04/06/2005] [Indexed: 05/02/2023]
Abstract
Our study investigated the adsorption/desorption by/from activated sludge flocs, dispersed in river water or in diluted wastewater, of organic compounds (C(11)-LAS, azoalbumin and azocasein) at concentrations relevant to environmental conditions. Activated sludge flocs, used as a model of biological aggregates, are characterized by a very heterogeneous matrix able to sorb the three organic compounds tested at 4 degrees C. The adsorbed amount of C(11)-LAS by activated sludge flocs was higher than that of azocasein or azoalbumin, as shown by the Freundlich parameters (K(ads)=8.6+/-1.7, 1.6+/-0.3 and 0.3+/-0.1 micromol(1-1/n)g(-1)l(1/n) for C(11)-LAS, azocasein and azoalbumin, respectively; n=3 sludges). C(11)-LAS sorption from activated sludge appeared to be partially reversible in river water, while a marked hysteresis phenomenon was observed for azocasein and azoalbumin, implying a low degree of reversibility in their exchange between activated sludge and river water. It has also been displayed that the conductivity variation of bulk water (comprised between 214 and 838 microS cm(-1)) exerted no dramatic effect on the C(11)-LAS desorption from activated sludge flocs, while a little effect of it on azocasein desorption was observed. Thus, biological aggregates as activated sludge flocs can serve as an intermediate carrier for C(11)-LAS, while it represents a sink for proteins.
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Affiliation(s)
- A Conrad
- LCPME, UMR 7564 CNRS-Université Henri Poincaré Nancy 1, Faculté de Pharmacie, Pôle de l'Eau, 15 avenue du Charmois, 54500 Vandoeuvre-lès-Nancy, France
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García MT, Campos E, Ribosa I, Latorre A, Sánchez-Leal J. Anaerobic digestion of linear alkyl benzene sulfonates: biodegradation kinetics and metabolite analysis. CHEMOSPHERE 2005; 60:1636-43. [PMID: 16083770 DOI: 10.1016/j.chemosphere.2005.02.048] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2004] [Revised: 02/01/2005] [Accepted: 02/14/2005] [Indexed: 05/03/2023]
Abstract
In the present work the effect of the alkyl chain length and the position of the sulfophenyl substituent of the linear alkylbenzene sulfonates (LAS) on their anaerobic biodegradability have been investigated. Degradation kinetics of the linear alkyl benzene sulfonates homologues, 2phiC10LAS, 2phiC12LAS and 2phiC14LAS, have been studied. It has been also investigated the effect of the isomer type on the degradation rate of the LAS molecule through the comparative study of the 2phiC10LAS and 5phiC10LAS isomers. Batch anaerobic biodegradation tests were performed using sludge from the anaerobic digester of a wastewater treatment plant as microorganisms source. Ultimate biodegradation was evaluated from the biogas production whereas primary biodegradation was determined by specific analysis of the surfactant. LAS homologues and isomers showed a negligible primary biodegradation under anaerobic conditions. Furthermore, analysis of sulfophenyl carboxilates (SPC) by LC-MS indicated a low and constant level of these LAS degradation metabolites over the test period. These data are consistent with a minimal transformation of the LAS parent molecule in the anaerobic digesters. On the other hand, the addition of the shortest alkyl chain length homologues, decyl and dodecylbenzene sulfonates, reduces the biogas production whereas the most hydrophobic homologue, the tetradecylbenzene sulfonate, enhances the biogas production. This LAS homologue seems to increase the availability of organic compounds sorbed on the anaerobic sludge promoting their biodegradation.
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Affiliation(s)
- M T García
- Department of Surfactant Technology, IIQAB-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
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Jacobsen AM, Mortensen GK, Hansen HCB. Degradation and mobility of linear alkylbenzene sulfonate and nonylphenol in sludge-amended soil. JOURNAL OF ENVIRONMENTAL QUALITY 2004; 33:232-240. [PMID: 14964377 DOI: 10.2134/jeq2004.2320] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Degradation and mobility of the surfactants linear alkylbenzene sulfonate (LAS) and nonylphenol (NP) were investigated in a lysimeter study using a sandy loam soil and 45-cm soil columns. Anaerobically digested sewage sludge was incorporated in the top-15-cm soil layer to an initial content of 38 mg LAS and 0.56 mg NP kg(-1) dry wt., respectively. Spring barley (Hordeum vulgare L.) was sown onto the columns. The lysimeters were placed outdoors and therefore received natural precipitation, but were also irrigated to a total amount of water equivalent to 700 mm of precipitation. Leachate and soil samples from three soil layers were collected continuously during a growth period of 110 d. Leachate samples and soil extracts were concentrated by solid-phase extraction (SPE) and analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. The concentrations in the top-15-cm soil layer declined to 25 and 45% of the initial contents for LAS and NP, respectively, within the first 10 d of the study. At the end of the study, less than 1% LAS was left, while the NP content was below the detection limit. Assuming first-order degradation kinetics, half-lives of 20 and 37 d were estimated for LAS and NP, respectively. The surfactants were not measured in leachate samples in concentrations above the analytical detection limits of 4.0 and 0.5 microg L(-1) for LAS and NP, respectively. In addition, neither LAS nor NP were measured in concentrations above the detection limits of 150 and 50 microg kg(-1) dry wt., respectively, in soil layers below the 15 cm of sludge incorporation, indicating negligible downward transport of the surfactants in the lysimeters.
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Affiliation(s)
- Anne Marie Jacobsen
- Risø National Laboratory, Plant Research Department, Building PRD-301, Post Office Box 49, DK-4000 Roskilde, Denmark.
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