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Bierbaum T, Hansen SK, Poudel B, Haslauer C. Investigating rate-limited sorption, sorption to air-water interfaces, and colloid-facilitated transport during PFAS leaching. Environ Sci Pollut Res Int 2023; 30:121529-121547. [PMID: 37957494 PMCID: PMC10724089 DOI: 10.1007/s11356-023-30811-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/28/2023] [Indexed: 11/15/2023]
Abstract
Various sorption processes affect leaching of per- and polyfluoroalkyl substances (PFAS) such as PFOA and PFOS. The objectives of this study are to (1) compare rate-limited leaching in column and lysimeter experiments, (2) investigate the relevance of sorption to air-water interfaces (AWI), and (3) examine colloid-facilitated transport as a process explaining early experimental breakthrough. A continuum model (CM) with two-domain sorption is used to simulate equilibrium and rate-limited sorption. A random walk particle tracking (PT) model was developed and applied to analyze complex leaching characteristics. Results show that sorption parameters derived from column experiments underestimate long-term PFOA leaching in lysimeter experiments due to early depletion, suggesting that transformation of precursors contributes to the observed long-term leaching in the lysimeters (approximately 0.003 µg/kg/d PFOA). Both models demonstrate that sorption to AWI is the dominant retention mechanism for PFOS in lysimeter experiments, with retardation due to AWI being 3 (CM) to 3.7 (PT) times higher than retardation due to solid phase sorption. Notably, despite a simplified conception of AWI sorption, the PT results are closer to the observations. The PT simulations demonstrate possible colloid-facilitated transport at early time; however, results using substance-specific varying transport parameters align better with the observations, which should be equal if colloid-facilitated transport without additional kinetics is the sole mechanism affecting early breakthrough. Possibly, rate-limited sorption to AWI is relevant during the early stages of the lysimeter experiment. Our findings demonstrate that rate-limited sorption is less relevant for long-term leaching under field conditions compared to transformation of precursors and that sorption to AWI can be the dominant retention mechanism on contaminated sites. Moreover, they highlight the potential of random walk particle tracking as a practical alternative to continuum models for estimating the relative contributions of various retention mechanisms.
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Affiliation(s)
- Thomas Bierbaum
- Research Facility for Subsurface Remediation (VEGAS), University of Stuttgart, Institute for Modelling Environmental Systems (IWS), Pfaffenwaldring 61, 70569, Stuttgart, Germany.
| | - Scott K Hansen
- Ben-Gurion University of the Negev, Zuckerberg Institute for Water Research, 8499000, Midreshet Ben-Gurion, Israel
| | - Bikash Poudel
- Research Facility for Subsurface Remediation (VEGAS), University of Stuttgart, Institute for Modelling Environmental Systems (IWS), Pfaffenwaldring 61, 70569, Stuttgart, Germany
| | - Claus Haslauer
- Research Facility for Subsurface Remediation (VEGAS), University of Stuttgart, Institute for Modelling Environmental Systems (IWS), Pfaffenwaldring 61, 70569, Stuttgart, Germany
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Zhang W, Liang Y, Sun H, Wang X, Zhou Q, Tang X. Initial soil moisture conditions affect the responses of colloid mobilisation and associated cadmium transport in opposite directions. J Hazard Mater 2023; 448:130850. [PMID: 36764259 DOI: 10.1016/j.jhazmat.2023.130850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 12/19/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
The effects of initial soil moisture on colloid-associated transport are still poorly understood given the well-recognized significance of colloid-facilitated transport of strongly-sorbing contaminants. In this study, Cd leaching was sequentially conducted in an intact soil column under three initial moisture conditions (near saturation, field capacity and dryness). Soil colloids were always the dominant carriers for Cd. However, upon the lowering of initial soil moisture, increased transport of colloids (96.2→101.0→168.2 mg) was observed, surprisingly, along with decreased transport of colloid-associated Cd (C-Cd) (23.9→10.7→8.2 µg) and enrichment factor (248.4→105.9→48.8 mg/kg) of Cd on colloids, resulting from pH reduction which increased Cd desorption and colloid size increase and/or ζ-potential decrease that showed lower affinity for Cd. Correlation, redundancy analysis and structural equation modelling revealed the dominantly positive role of colloids, EC plus cations (Ca2+ and Mg2+) in the release of C-Cd and dissolved Cd (D-Cd), respectively, under initial moistures of near saturation and field capacity. Under initially dry conditions, soil water potential showed dominantly negative effects on the transport of both C-Cd and D-Cd. These findings highlighted the critical role of initial moisture conditions in modulating colloid-facilitated Cd mobilisation, providing insights into the environmental risk assessment of heavy metals in other leaching scenarios.
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Affiliation(s)
- Wei Zhang
- Department of Land Resources Management, School of Public Administration, Chongqing Technology and Business University, Chongqing 400067, China; Chongqing Key Laboratory of Spatial Data Mining and Big Data Integration for Ecology and Environment, Chongqing 400067, China
| | - Yun Liang
- School of Environment and Resources, Chongqing Technology and Business University, Chongqing 400067, China
| | - Honglei Sun
- Yunnan Hexu Environmental Technology Co., Ltd., Mianyang 621002, China
| | - Xingmin Wang
- School of Environment and Resources, Chongqing Technology and Business University, Chongqing 400067, China
| | - Qigang Zhou
- Chongqing Key Laboratory of Spatial Data Mining and Big Data Integration for Ecology and Environment, Chongqing 400067, China
| | - Xiangyu Tang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou 311300, China.
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Tan B, Liu C, Tan X, You X, Dai C, Liu S, Li J, Li N. Heavy metal transport driven by seawater-freshwater interface dynamics: The role of colloid mobilization and aquifer pore structure change. Water Res 2022; 217:118370. [PMID: 35405553 DOI: 10.1016/j.watres.2022.118370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/13/2022] [Accepted: 03/25/2022] [Indexed: 06/14/2023]
Abstract
Co-transport of colloidal substances and pollutants is a pivotal link that significantly affects the environment of coastal groundwater. The effect of colloid mobilization and aquifer pore structure change on heavy metal transport driven by seawater-freshwater interface dynamics is not fully understood. In this study, packed column experiments were conducted to model the seawater intrusion (SWI) and freshwater replenishment (FWR) processes using a sampled medium from a coastal sandy aquifer. Hydrodynamic, hydrochemical variables, and heavy metal (Pb, Cu, Cd) transport during the propagation of the seawater-freshwater interface were tested and analyzed. During the SWI stage, cation exchange induced heavy metal liberations, and it developed peak concentrations synchronized with the seawater-freshwater interface at the pore volume of 1.00. The colloid-facilitated transport for heavy metals was the predominant mechanism in the FWR stage, characterized by a peak release lagging the interface propagation by approximately 0.5 pore volumes. Because the colloidal fraction was mobilized during aquifer desalination, it lagged behind the decline of the salinity gradient. Furthermore, Derjaguin-Landau-Verwey-Overbeek (DLVO) calculations explained that the replenishment decreased the depth of the secondary energy minimum of the colloids; meanwhile, the thickness of the electrical double layer increased from 0.63 nm to 10.14 nm, resulting in a repulsive energy barrier up to 3,213 kT. The transport of colloids led to a reduction in porosity from 18.16% to 2.28% of the total immobile domain. At these times, the dimension of the transported colloids evolved, showing a size-selective transport and therefore regulating the total emission fluxes of the heavy metals. These mechanisms were proposed to be incorporated in colloid filtration theory for targeting the coastal scenario.
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Affiliation(s)
- Bo Tan
- State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower, Sichuan University, 610065 Chengdu, Sichuan, China
| | - Chao Liu
- State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower, Sichuan University, 610065 Chengdu, Sichuan, China
| | - Xiao Tan
- State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower, Sichuan University, 610065 Chengdu, Sichuan, China
| | - Xueji You
- Department of Hydraulic Engineering, College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Chaomeng Dai
- Department of Hydraulic Engineering, College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Shuguang Liu
- Department of Hydraulic Engineering, College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Jun Li
- State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower, Sichuan University, 610065 Chengdu, Sichuan, China.
| | - Naiwen Li
- State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resource & Hydropower, Sichuan University, 610065 Chengdu, Sichuan, China
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Borthakur A, Cranmer BK, Dooley GP, Blotevogel J, Mahendra S, Mohanty SK. Release of soil colloids during flow interruption increases the pore-water PFAS concentration in saturated soil. Environ Pollut 2021; 286:117297. [PMID: 33971474 DOI: 10.1016/j.envpol.2021.117297] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/28/2021] [Accepted: 04/30/2021] [Indexed: 06/12/2023]
Abstract
Groundwater flow through aquifer soils or packed bed systems can fluctuate for various reasons, which could affect the concentration of natural colloids and per- and polyfluoroalkyl substances (PFAS) in the pore water. In such cases, PFAS concentration could either decrease due to matrix diffusion of PFAS or increase by the detachment of colloids carrying PFAS. Yet, the effect of flow fluctuation on PFAS transport or release in porous media has not been examined. To examine the relative importance of either process, we interrupted the flow during an injection of groundwater spiked with perfluorobutanoic acid (PFBA), perfluorooctanoic acid (PFOA), and bromide as conservative tracer through clay-rich soil, so that diffusive transport would be prominent during flow interruption. After flow interruption, the PFAS concentration did not decrease indicating an insignificant contribution of matrix diffusion. The concentration increased, potentially due to enhanced release of colloid-associated PFAS. Analysis of samples before and after flow interruption by particle size analysis and SEM confirmed an increase in soil colloid concentration after the flow interruption. XRD analysis of soil and the colloids proved that PFAS were associated with specific sites of the colloids. Due to a higher affinity of PFOA to soil colloids, the total PFOA concentration in the effluent samples increased more than PFBA after the flow interruption process. The results indicate that colloids may have a disproportionally higher role in the transport of PFAS in conditions that release colloids from porous media. Thus, fluctuations in groundwater flow can increase this colloid facilitated mobility of PFAS.
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Affiliation(s)
- Annesh Borthakur
- Department of Civil and Environmental Engineering, University of California, Los Angeles, USA
| | - Brian K Cranmer
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, USA
| | - Gregory P Dooley
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, USA
| | - Jens Blotevogel
- Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, USA
| | - Shaily Mahendra
- Department of Civil and Environmental Engineering, University of California, Los Angeles, USA
| | - Sanjay K Mohanty
- Department of Civil and Environmental Engineering, University of California, Los Angeles, USA.
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Tang XY, Katou H, Suzuki K. Liming effects on dissolved and colloid-associated transport of cadmium in soil under intermittent simulated rainfall. J Hazard Mater 2020; 400:123244. [PMID: 32593027 DOI: 10.1016/j.jhazmat.2020.123244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/04/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Liming has been regarded as an effective measure to reduce the bioavailability and mobility of cadmium (Cd) in soil. However, its effect on Cd transport in colloid-associated form remains unclear. In this study, relative importance of dissolved and colloid-associated transport of Cd was explored in columns packed with moist soil aggregates (diameter <2 mm) under intermittent simulated rainfall of distilled water or 5 mmol L-1 CaCl2 solution. The Cd2+/Ca2+ exchange selectivity coefficient determined in column experiments displayed gradual decreases with decreasing ionic strength. It is proposed that the exchange selectivity coefficient determined by repeated batch extraction can be used to predict Cd discharge in dissolved form in column effluent. Colloid-associated Cd was the main Cd form in the first flushing effluent sample upon resuming infiltration of distilled water. Otherwise, Cd was transported mainly in dissolved form, accounting for 81-93 % and 54-72 % of total Cd discharge for unlimed soils and limed soils, respectively. Liming remarkably reduced dissolved Cd concentration but only slightly enhanced colloidal Cd transport. Cd was enriched on colloids, and the enrichment factor was enhanced by liming. Colloidal Cd transport through preferential pathways (e.g., macropores, shrinkage cracks, tile drains) should be paid due attention.
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Affiliation(s)
- Xiang-Yu Tang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, 311300, China; Key Laboratory of Mountain Surface Processes and Ecological regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization, Tsukuba, 305-8604, Japan.
| | - Hidetaka Katou
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization, Tsukuba, 305-8604, Japan
| | - Katsuhiro Suzuki
- Central Region Agricultural Research Center, National Agriculture and Food Research Organization, Joetsu, 943-0193, Japan
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Dai C, Zhou H, You X, Duan Y, Tu Y, Liu S, Zhou F, Hon LK. Silica colloids as non-carriers facilitate Pb 2+ transport in saturated porous media under a weak adsorption condition: effects of Pb 2+ concentrations. Environ Sci Pollut Res Int 2020; 27:15188-15197. [PMID: 32072419 DOI: 10.1007/s11356-020-08064-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/11/2020] [Indexed: 06/10/2023]
Abstract
Transport of environmental pollutants in groundwater systems can be greatly influenced by colloids. In this study, the cotransport of Pb2+ and silica (SiO2) colloids at different Pb2+ concentrations was systematically investigated by batch adsorption and saturated sand column experiments. Results showed that SiO2 colloids had low adsorption capacity for Pb2+ (less than 1% of the input) compared with sands. In saturated porous media, SiO2 colloids showed a high mobility; however, with the increase of Pb2+ concentration in the sand column, the mobility of SiO2 colloids gradually decreased. Notably, SiO2 colloids could facilitate Pb2+ transport, although they did not serve as effective carriers of Pb2+. Under the condition of low Pb2+ concentration, SiO2 colloids promoted the Pb2+ transport mainly through the way of "transport channel," while changing the porosity of the medium and masking medium adsorption sites were the main mechanisms of SiO2 colloid-facilitated Pb2+ transport under the condition of high Pb2+ concentration. The discovery of this non-adsorption effect of colloids would improve our understanding of colloid-facilitated Pb2+ transport in saturated porous media, which provided new insights into the role of colloids, especially colloids with weak Pb2+ adsorption capacity, in Pb2+ occurrence and transport in soil-groundwater systems.
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Affiliation(s)
- Chaomeng Dai
- College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, People's Republic of China
| | - Hui Zhou
- College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, People's Republic of China
| | - Xueji You
- College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, People's Republic of China
| | - Yanping Duan
- School of Environmental and Geographical Sciences, Shanghai Normal University, No. 100 Guilin Rd., Shanghai, 200234, People's Republic of China.
| | - Yaojen Tu
- School of Environmental and Geographical Sciences, Shanghai Normal University, No. 100 Guilin Rd., Shanghai, 200234, People's Republic of China
| | - Shuguang Liu
- College of Civil Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, People's Republic of China
- The Yangtze River Water Environment Key Laboratory of the Ministry of Education, Tongji University, 1239 Siping Road, Shanghai, 200092, People's Republic of China
| | - Feng Zhou
- Sino-France Institute of Earth Systems Science, Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, People's Republic of China
| | - Leong Kah Hon
- Department Environment Engineering, Faculty Engineering & Green Technology, Universiti Tunku Abdul Rahman, 31900, Kampar, Perak, Malaysia
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Telfeyan K, Reimus PW, Boukhalfa H, Ware SD. Aging effects on Cesium-137 ( 137Cs) sorption and transport in association with clay colloids. J Colloid Interface Sci 2020; 566:316-26. [PMID: 32007742 DOI: 10.1016/j.jcis.2020.01.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/23/2019] [Accepted: 01/12/2020] [Indexed: 11/22/2022]
Abstract
Migration of radionuclides via colloid-facilitated transport is an important component of nuclear repository performance models. 137Cs sorption to bentonite colloids follows multi-site behavior, with sorption to weak sites being a rapid process and sorption to strong sites having slow kinetics. Experiments in this study targeted desorption of 137Cs from strong sites on the colloids by placing the 137Cs-bearing colloids in contact with a strongly-sorbing zeolite material that competes with the colloids for 137Cs sorption. Batch and column experiments were conducted to examine the effects of aging (i.e., increased contact time between 137Cs and colloids) on colloid-facilitated transport of 137Cs through crushed analcime columns. A larger proportion of 137Cs-bearing colloids eluted through a series of columns when the colloids were aged for 1200 days prior to injection in comparison to unaged colloids. Aging the colloids increased the partitioning of 137Cs to the colloids by nearly 20% after 1200 h. Slow desorption (0.27 hr-1) from the strong sites resulted in an increase of the Cs fraction bound to the strong sites from 0.365 to 0.87 by the second column injection, resulting in increased colloid-facilitated transport of Cs through strongly-sorbing zeolites from 0 in the second unaged column to 10% in the second aged column.
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Rod K, Um W, Chun J, Wu N, Yin X, Wang G, Neeves K. Effect of chemical and physical heterogeneities on colloid-facilitated cesium transport. J Contam Hydrol 2018; 213:22-27. [PMID: 29657081 DOI: 10.1016/j.jconhyd.2018.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 03/09/2018] [Accepted: 03/29/2018] [Indexed: 06/08/2023]
Abstract
A set of column experiments was conducted to investigate the chemical and physical heterogeneity effect on colloid facilitated transport under slow pore velocity conditions. Pore velocities were kept below 100 cm d-1 for all experiments. Glass beads were packed into columns establishing four different conditions: 1) homogeneous, 2) mixed physical heterogeneity, 3) sequentially layered physical heterogeneity, and 4) chemical heterogeneity. The homogeneous column was packed with glass beads (diameter 500-600 μm), and physical heterogeneities were created by sequential layering or mixing two sizes of glass bead (500-600 μm and 300-400 μm). A chemical heterogeneity was created using 25% of the glass beads coated with hydrophobic molecules (1H-1H-2H-2H-perfluorooctyltrichlorosilane) mixed with 75% pristine glass beads (all 500-600 μm). Input solution with 0.5 mM CsI and 50 mg L-1 colloids (1-μm diameter SiO2) was pulsed into columns under saturated conditions. The physical heterogeneity in the packed glass beads retarded the transport of colloids compared to homogeneous (R = 25.0), but showed only slight differences between sequentially layered (R = 60.7) and mixed heterogeneity(R = 62.4). The column with the chemical, hydrophobic/hydrophilic, heterogeneity removed most of the colloids from the input solution. All column conditions stripped Cs from colloids onto the column matrix of packed glass beads.
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Affiliation(s)
- Kenton Rod
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Wooyong Um
- Pacific Northwest National Laboratory, Richland, WA 99354, USA; Pohang University of Science and Technology (POSTECH), Pohang 37673, South Korea.
| | - Jaehun Chun
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
| | - Ning Wu
- Colorado School of Mines, Golden, CO 80401, USA
| | - Xialong Yin
- Colorado School of Mines, Golden, CO 80401, USA
| | - Guohui Wang
- Pacific Northwest National Laboratory, Richland, WA 99354, USA
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Tran E, Klein Ben-David O, Teutch N, Weisbrod N. Influence of heteroaggregation processes between intrinsic colloids and carrier colloids on cerium(III) mobility through fractured carbonate rocks. Water Res 2016; 100:88-97. [PMID: 27183207 DOI: 10.1016/j.watres.2016.04.075] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/27/2016] [Accepted: 04/28/2016] [Indexed: 06/05/2023]
Abstract
Colloid facilitated transport of radionuclides has been implicated as a major transport vector for leaked nuclear waste in the subsurface. Sorption of radionuclides onto mobile carrier colloids such as bentonite and humic acid often accelerates their transport through saturated rock fractures. Here, we employ column studies to investigate the impact of intrinsic, bentonite and humic acid colloids on the transport and recovery of Ce(III) through a fractured chalk core. Ce(III) recovery where either bentonite or humic colloids were added was 7.7-26.9% Ce for all experiments. Greater Ce(III) recovery was observed when both types of carrier colloids were present (25.4-37.4%). When only bentonite colloids were present, Ce(III) appeared to be fractionated between chemical sorption to the bentonite colloid surfaces and heteroaggregation of bentonite colloids with intrinsic carbonate colloids, precipitated naturally in solution. However, scanning electron microscope (SEM) images and colloid stability experiments reveal that in suspensions of humic acid colloids, colloid-facilitated Ce(III) migration results only from the latter attachment mechanism rather than from chemical sorption. This observed heteroaggregation of different colloid types may be an important factor to consider when predicting potential mobility of leaked radionuclides from geological repositories for spent fuel located in carbonate rocks.
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Affiliation(s)
- Emily Tran
- The Zuckerburg Institute for Water Research, The Jacob Blaustein Institutes for Desert Studies, Ben Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben Gurion, 8499000, Israel
| | - Ofra Klein Ben-David
- Nuclear Research Center of the Negev, Negev, PO Box 9001, Beer Sheva, 84190, Israel
| | - Nadya Teutch
- Geological Survey of Israel, 30 Malkhe Israel St., Jerusalem, 95501, Israel
| | - Noam Weisbrod
- The Zuckerburg Institute for Water Research, The Jacob Blaustein Institutes for Desert Studies, Ben Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben Gurion, 8499000, Israel.
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Zhou D, Thiele-Bruhn S, Arenz-Leufen MG, Jacques D, Lichtner P, Engelhardt I. Impact of manure-related DOM on sulfonamide transport in arable soils. J Contam Hydrol 2016; 192:118-128. [PMID: 27450276 DOI: 10.1016/j.jconhyd.2016.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 06/28/2016] [Accepted: 07/15/2016] [Indexed: 06/06/2023]
Abstract
Field application of livestock manure introduces colloids and veterinary antibiotics, e.g. sulfonamides (SAs), into farmland. The presence of manure colloids may potentially intensify the SAs-pollution to soils and groundwater by colloid-facilitated transport. Transport of three SAs, sulfadiazine (SDZ), sulfamethoxypyridazine (SMPD), and sulfamoxole (SMOX), was investigated in saturated soil columns with and without manure colloids from sows and farrows, weaners, and fattening pigs. Experimental results showed that colloid-facilitated transport of SMOX was significant in the presence of manure colloids from fattening pigs with low C/N ratio, high SUVA280nm and protein C, while manure colloids from sows and farrows and weaners had little effect on SMOX transport. In contrast, only retardation was observed for SDZ and SMPD when manure colloids were present. Breakthrough curves (BTCs) of colloids and SAs were replicated well by a newly developed numerical model that considers colloid-filtration theory, competitive kinetic sorption, and co-transport processes. Model results demonstrate that mobile colloids act as carriers for SMOX, while immobile colloids block SMOX from sorbing onto the soil. The low affinity of SMOX to sorb on immobile colloids prevents aggregation and also promotes SMOX's colloid-facilitated transport. Conversely, the high affinity of SDZ and SMPD to sorb on all types of immobile colloids retarded their transport. Thus, manure properties play a fundamental role in increasing the leaching risk of hydrophobic sulfonamides.
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Affiliation(s)
- Dan Zhou
- Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich, Germany; Department of Hydrogeology and Hydrochemistry, TU Freiberg, Freiberg, Germany.
| | - Sören Thiele-Bruhn
- Department of Soil Science, University of Trier, Behringstr. 21, Trier, Germany
| | - Martina Gesine Arenz-Leufen
- Department of Soil Science, University of Trier, Behringstr. 21, Trier, Germany; Dr Knoell Consult GmbH, Marie-Curie-Straße 8, Leverkusen, Germany
| | - Diederik Jacques
- Institute for Environment, Health and Safety (EHS), Belgian Nuclear Research Centre, Belgium
| | | | - Irina Engelhardt
- Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich, Germany; Department of Hydrogeology and Hydrochemistry, TU Freiberg, Freiberg, Germany
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