1
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Cardoso FS, Kadam AL, Nelson RC, Tomlin JW, Dahal D, Kuehner CS, Gudvangen G, Arduengo AJ, Burns JM, Aleshire SL, Snead DR, Qu F, Belmore K, Ahmad S, Agrawal T, Sieber JD, Donsbach KO. Practical and Scalable Two-Step Process for 6-(2-Fluoro-4-nitrophenyl)-2-oxa-6-azaspiro[3.3]heptane: A Key Intermediate of the Potent Antibiotic Drug Candidate TBI-223. Org Process Res Dev 2023; 27:1390-1399. [PMID: 37496954 PMCID: PMC10367134 DOI: 10.1021/acs.oprd.3c00148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Indexed: 07/28/2023]
Abstract
A low-cost, protecting group-free route to 6-(2-fluoro-4-nitrophenyl)-2-oxa-6-azaspiro[3.3]heptane (1), the starting material for the in-development tuberculosis treatment TBI-223, is described. The key bond forming step in this route is the creation of the azetidine ring through a hydroxide-facilitated alkylation of 2-fluoro-4-nitroaniline (2) with 3,3-bis(bromomethyl)oxetane (BBMO, 3). After optimization, this ring formation reaction was demonstrated at 100 g scale with isolated yield of 87% and final product purity of >99%. The alkylating agent 3 was synthesized using an optimized procedure that starts from tribromoneopentyl alcohol (TBNPA, 4), a commercially available flame retardant. Treatment of 4 with sodium hydroxide under Schotten-Baumann conditions closed the oxetane ring, and after distillation, 3 was recovered in 72% yield and >95% purity. This new approach to compound 1 avoids the previous drawbacks associated with the synthesis of 2-oxa-6-azaspiro[3,3]heptane (5), the major cost driver used in previous routes to TBI-223. The optimization and multigram scale-up results for this new route are reported herein.
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Affiliation(s)
- Flavio S.P. Cardoso
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - Appasaheb L. Kadam
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - Ryan C. Nelson
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - John W. Tomlin
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - Dipendra Dahal
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, Atlanta, Georgia 30332-0400, United States
| | - Christopher S. Kuehner
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, Atlanta, Georgia 30332-0400, United States
| | - Gard Gudvangen
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, Atlanta, Georgia 30332-0400, United States
| | - Anthony J. Arduengo
- School
of Chemistry and Biochemistry, Georgia Institute
of Technology, Atlanta, Georgia 30332-0400, United States
| | - Justina M. Burns
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - Sarah L. Aleshire
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - David R. Snead
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - Fengrui Qu
- Department
of Chemistry and Biochemistry, The University
of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Ken Belmore
- Department
of Chemistry and Biochemistry, The University
of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Saeed Ahmad
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
| | - Toolika Agrawal
- Department
of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, Virginia 23284-3208, United States
| | - Joshua D. Sieber
- Department
of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, Virginia 23284-3208, United States
| | - Kai Oliver Donsbach
- Medicines
for All Institute, Virginia Commonwealth
University, 737 N. 5th St., Box 980100, Richmond, Virginia 23298, United States
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2
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Sun J, Chen Y, Xiang Y, Ling L, Fang J, Shang C. Oxidative debromination of 2,2-bis(bromomethyl)-1,3-propanediol by UV/persulfate process and corresponding formation of brominated by-products. CHEMOSPHERE 2019; 228:735-743. [PMID: 31071560 DOI: 10.1016/j.chemosphere.2019.04.168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/12/2019] [Accepted: 04/22/2019] [Indexed: 06/09/2023]
Abstract
This study investigated the oxidative debromination of 2,2-bis(bromomethyl)-1,3-propanediol (BBMP), a widely used brominated flame retardant, and the corresponding formation of brominated by-products by the UV/persulfate process. The debromination of BBMP by the UV/persulfate process was primarily driven by sulfate radicals (SO4-) at pHs 4.0-6.0 and hydroxyl radicals (HO) at pHs 9.0-12.0. The debromination rate increased with increasing pH from 4.0 to 9.0 and remained the same at pHs 9.0 and 12.0. Bromate was formed through the oxidation of bromide released from BBMP mainly by SO4-, with free bromine as a key intermediate. Bromate formation increased with increasing pH from 4.0 to 6.0, while it remarkably decreased with increasing pH from 6.0 to 12.0. This was mainly due to the transformation of SO4- to HO and also the quenching of bromine atoms that were the key intermediate for the formation of free bromine, by hydroxyl ions at the alkaline pH. In addition, the oxidative debromination of BBMP resulted in a significant decrease in the concentrations of total organic bromine, but the formation of brominated acetic acids and unknown brominated organic by-products. The concentrations of brominated organic by-products firstly increased and then decreased with prolonged reaction time. Also, the formation of brominated organic by-products and genotoxicity at pH 9.0 were much lower than that at pH 6.0. In this study, we propose that the UV/persulfate process under mildly alkaline conditions not only debrominates BBMP efficiently but also eliminates the formation of bromate and brominated organic by-products and genotoxicity.
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Affiliation(s)
- Jianliang Sun
- School of Chemistry & Environment, South China Normal University, Guangzhou, China; Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Yu Chen
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Yingying Xiang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Li Ling
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China.
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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3
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Balaban N, Bernstein A, Gelman F, Ronen Z. Microbial degradation of the brominated flame retardant TBNPA by groundwater bacteria: laboratory and field study. CHEMOSPHERE 2016; 156:367-373. [PMID: 27183339 DOI: 10.1016/j.chemosphere.2016.04.127] [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: 02/09/2016] [Revised: 04/10/2016] [Accepted: 04/30/2016] [Indexed: 06/05/2023]
Abstract
In the present study, the biodegradation of the brominated flame retardant tribromoneopentylalcohol (TBNPA) by a groundwater enrichment culture was investigated using a dual carbon ((13)C/(12)C)- bromine ((81)Br/(79)Br) stable isotope analysis. An indigenous aerobic bacterial consortium was enriched from the polluted groundwater underlying an industrial site in the northern Negev Desert, Israel, where TBNPA is an abundant pollutant. Aerobic biodegradation was shown to be rapid, with complete debromination within a few days, whereas anaerobic biodegradation was not observed. Biodegradation under aerobic conditions was accompanied by a significant carbon isotope effect with an isotopic enrichment factor of ɛCbulk = -8.8‰ ± 1.5‰, without any detectable bromine isotope fractionation. It was found that molecular oxygen is necessary for biodegradation to occur, suggesting an initial oxidative step. Based on these results, it was proposed that H abstraction from the C-H bond is the first step of TBNPA biodegradation under aerobic conditions, and that the C-H bond cleavage results in the formation of unstable intermediates, which are rapidly debrominated. A preliminary isotopic analysis of TBNPA in the groundwater underlying the industrial area revealed that there are no changes in the carbon and bromine isotope ratio values downstream of the contamination source. Considering that anoxic conditions prevail in the groundwater of the contaminated site, the lack of isotope shifts in TBNPA indicates the lack of TBNPA biodegradation in the groundwater, in accordance with our findings.
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Affiliation(s)
- Noa Balaban
- Department of Environmental Hydrology & Microbiology (EHM), The Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
| | - Anat Bernstein
- Department of Environmental Hydrology & Microbiology (EHM), The Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
| | - Faina Gelman
- Geological Survey of Israel, 30 Malkhei Israel St., Jerusalem 95501, Israel.
| | - Zeev Ronen
- Department of Environmental Hydrology & Microbiology (EHM), The Zuckerberg Institute for Water Research (ZIWR), The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
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4
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Kozell A, Yecheskel Y, Balaban N, Dror I, Halicz L, Ronen Z, Gelman F. Application of dual carbon-bromine isotope analysis for investigating abiotic transformations of tribromoneopentyl alcohol (TBNPA). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:4433-4440. [PMID: 25723316 DOI: 10.1021/es504887d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Many of polybrominated organic compounds, used as flame retardant additives, belong to the group of persistent organic pollutants. Compound-specific isotope analysis is one of the potential analytical tools for investigating their fate in the environment. However, the isotope effects associated with transformations of brominated organic compounds are still poorly explored. In the present study, we investigated carbon and bromine isotope fractionation during degradation of tribromoneopentyl alcohol (TBNPA), one of the widely used flame retardant additives, in three different chemical processes: transformation in aqueous alkaline solution (pH 8); reductive dehalogenation by zero-valent iron nanoparticles (nZVI) in anoxic conditions; oxidative degradation by H2O2 in the presence of CuO nanoparticles (nCuO). Two-dimensional carbon-bromine isotope plots (δ(13)C/Δ(81)Br) for each reaction gave different process-dependent isotope slopes (Λ(C/Br)): 25.2 ± 2.5 for alkaline hydrolysis (pH 8); 3.8 ± 0.5 for debromination in the presence of nZVI in anoxic conditions; ∞ in the case of catalytic oxidation by H2O2 with nCuO. The obtained isotope effects for both elements were generally in agreement with the values expected for the suggested reaction mechanisms. The results of the present study support further applications of dual carbon-bromine isotope analysis as a tool for identification of reaction pathway during transformations of brominated organic compounds in the environment.
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Affiliation(s)
- Anna Kozell
- †Geological Survey of Israel, 30 Malhei Israel Street, Jerusalem 95501, Israel
- ‡Department of Chemistry, The Hebrew University, Jerusalem 91904, Israel
| | - Yinon Yecheskel
- §Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Noa Balaban
- ∥Zuckerberg Institute for Water Research, Department of Environmental Hydrology and Microbiology, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Sede Boqer 84990, Israel
| | - Ishai Dror
- §Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Ludwik Halicz
- †Geological Survey of Israel, 30 Malhei Israel Street, Jerusalem 95501, Israel
- ⊥Biological and Chemical Research Centre, University of Warsaw, 02-089, Poland
| | - Zeev Ronen
- ∥Zuckerberg Institute for Water Research, Department of Environmental Hydrology and Microbiology, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Sede Boqer 84990, Israel
| | - Faina Gelman
- †Geological Survey of Israel, 30 Malhei Israel Street, Jerusalem 95501, Israel
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5
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Yecheskel Y, Dror I, Berkowitz B. Catalytic degradation of brominated flame retardants by copper oxide nanoparticles. CHEMOSPHERE 2013; 93:172-177. [PMID: 23786809 DOI: 10.1016/j.chemosphere.2013.05.026] [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: 03/07/2013] [Revised: 05/05/2013] [Accepted: 05/14/2013] [Indexed: 06/02/2023]
Abstract
The catalytic degradation of two brominated flame retardants (BFRs), tribromoneopentyl alcohol (TBNPA) and 2,4 dibromophenol (2,4-DBP) by copper oxide nanoparticles (nCuO) was investigated. The degradation kinetics, the debromination, and the formation of intermediates by nCuO catalysis were also compared to Fenton oxidation and nano zero-valent iron (nZVI) reduction methods. BFRs have been added to various products like plastic, textile, electronics and synthetic polymers at growing rates. In spite of the clear advantages of reducing fire damages, many of these BFRs may be released to the environment after their beneficial use and become contaminants. The two studied BFRs were fully degraded with sufficient time (hours to days) and oxidation agent (H2O2). Shorter reaction times showed differences in reaction pathway and kinetics. The 2,4-DBP showed faster degradation than TBNPA, by nCuO catalysis. Relatively high resistance to degradation was recorded for 2,4-DBP with nZVI, yielding 20% degradation after 24h, while the TBNPA was degraded by 85% within 12h. Electron Spin Resonance (ESR) measurements show generation of both hydroxyl and superoxide radicals. In addition, inhibition of 2,4-DBP degradation in the presence of spin traps implies a radical degradation mechanism. A catalytic mechanism for radical generation and BFR degradation by nCuO is proposed. It is further suggested that H2O2 plays an essential role in the activation of the catalyst.
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Affiliation(s)
- Yinon Yecheskel
- Department of Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot, Israel
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6
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7
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Dror I, Jacov OM, Cortis A, Berkowitz B. Catalytic transformation of persistent contaminants using a new composite material based on nanosized zero-valent iron. ACS APPLIED MATERIALS & INTERFACES 2012; 4:3416-3423. [PMID: 22680618 DOI: 10.1021/am300402q] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A new composite material based on deposition of nanosized zerovalent iron (nZVI) particles and cyanocobalamine (vitamin B12) on a diatomite matrix is presented, for catalytic transformation of organic contaminants in water. Cyanocobalamine is known to be an effective electron mediator, having strong synergistic effects with nZVI for reductive dehalogenation reactions. This composite material also improves the reducing capacity of nZVI by preventing agglomeration of iron nanoparticles, thus increasing their active surface area. The porous structure of the diatomite matrix allows high hydraulic conductivity, which favors channeling of contaminated water to the reactive surface of the composite material resulting in faster rates of remediation. The composite material rapidly degrades or transforms completely a large spectrum of water contaminants, including halogenated solvents like TCE, PCE, and cis-DCE, pesticides like alachlor, atrazine and bromacyl, and common ions like nitrate, within minutes to hours. A field experiment where contaminated groundwater containing a mixture of industrial and agricultural persistent pollutants was conducted together with a set of laboratory experiments using individual contaminant solutions to analyze chemical transformations under controlled conditions.
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Affiliation(s)
- Ishai Dror
- Department of Environmental Sciences and Energy Research, Weizmann Institute of Science , Rehovot, 76100 Israel
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8
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Ezra S, Bilkis I, Feinstein S, Adar E, Ganor J. Chemical degradation of 2,2-bis(bromomethyl)propan-1,3-diol (DBNPG) in alkaline conditions. CHEMOSPHERE 2010; 79:476-481. [PMID: 20189218 DOI: 10.1016/j.chemosphere.2010.01.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Revised: 01/11/2010] [Accepted: 01/12/2010] [Indexed: 05/28/2023]
Abstract
The mechanism and kinetics of the spontaneous decomposition of 2,2-bis(bromomethyl)propan-1,3-diol (DBNPG) and its decomposition daughter products were determined in aqueous solution at a temperatures range between 30 and 70 degrees C and pH from 7.0 to 9.5. DBNPG decomposition in basic aqueous solutions involves release of bromide ions through a sequential formation of 3-bromomethyl-3-hydroxymethyloxetane (BMHMO) and 2,6-dioxaspiro[3.3]heptane (DOH). DBNPG decomposition into BMHMO is a two-stage reaction. The first stage is an acid/base equilibrium, in which an alkoxide is formed. In the second stage, DBNPG predominantly undergoes an intramolecular nucleophilic substitution to form the BMHMO. The transformation rate increases with the pH and the energy barrier for the degradation is 98 kJ mol(-1). Good agreement was found between the rate coefficients derived from variations in the organic molecules concentrations and those determined from the changes in the Br(-) concentration. DBNPG is one of the most abundant pollutants in a studied polluted aquitard underneath industrial park in the northern Negev, Israel, and together with its by-products pose an environmental hazard. DBNPG half-life is estimated to be about 65 years. This implies that high concentrations of DBNPG will persist in the aquifer long after the elimination of all its sources.
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Affiliation(s)
- Shai Ezra
- Water Quality Division, Mekorot, Israel National Water Co., P.O.B 2012, 9 Lincoln St., Tel Aviv 61201, Israel.
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9
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Krivorot M, Oren Y, Talmon Y, Gilron J. Determination of Tribromo-neopentyl Alcohol Micelle Distribution Coefficients in Single and Mixture Solutions for Evaluation of Micellar Enhanced Ultrafiltration Feasibility in Treating Contaminated Groundwater. Ind Eng Chem Res 2009. [DOI: 10.1021/ie8011352] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M. Krivorot
- Zuckerberg Institute for Water Research and Unit of Environmental Engineering, Ben Gurion University of the Negev, POB 653, Beer Sheva, 84105, Israel, and Faculty of Chemical Engineering, Technion—Israel Institute of Technology, Haifa, 32000, Israel
| | - Y. Oren
- Zuckerberg Institute for Water Research and Unit of Environmental Engineering, Ben Gurion University of the Negev, POB 653, Beer Sheva, 84105, Israel, and Faculty of Chemical Engineering, Technion—Israel Institute of Technology, Haifa, 32000, Israel
| | - Y. Talmon
- Zuckerberg Institute for Water Research and Unit of Environmental Engineering, Ben Gurion University of the Negev, POB 653, Beer Sheva, 84105, Israel, and Faculty of Chemical Engineering, Technion—Israel Institute of Technology, Haifa, 32000, Israel
| | - J. Gilron
- Zuckerberg Institute for Water Research and Unit of Environmental Engineering, Ben Gurion University of the Negev, POB 653, Beer Sheva, 84105, Israel, and Faculty of Chemical Engineering, Technion—Israel Institute of Technology, Haifa, 32000, Israel
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10
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Kutchko BG, Strazisar BR, Dzombak DA, Lowry GV, Thaulow N. Degradation of well cement by CO2 under geologic sequestration conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:4787-92. [PMID: 17695930 DOI: 10.1021/es062828c] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Experiments were conducted to assess the durability of cements in wells penetrating candidate formations for geologic sequestration of CO2. These experiments showed a significant variation in the initial degradation (9 days of exposure) based on the curing conditions. The high-temperature (50 degrees C) and high-pressure (30.3 MPa) curing environment increased the degree of hydration and caused a change in the microstructure and distribution of the Ca(OH)2(s) phase within the cement. Cement cured at 50 degrees C and 30.3 MPa (representing sequestration conditions) proved to be more resistant to carbonic acid attack than cement cured at 22 degrees C and 0.1 MPa. The cement cured at 50 degrees C and 30.3 MPa exhibited a shallower depth of degradation and displayed a well-defined carbonated zone as compared to cement cured under ambient conditions. This is likely due to smaller, more evenly distributed Ca(OH)2(s) crystals that provide a uniform and effective barrier to CO2 attack.
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Affiliation(s)
- Barbara G Kutchko
- United States Department of Energy, National Energy Technology Laboratory, Pittsburgh, Pennsylvania 15236, USA
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11
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Ezra S, Feinstein S, Yakirevich A, Adar E, Bilkis I. Retardation of organo-bromides in a fractured chalk aquitard. JOURNAL OF CONTAMINANT HYDROLOGY 2006; 86:195-214. [PMID: 16690162 DOI: 10.1016/j.jconhyd.2006.02.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2005] [Revised: 02/10/2006] [Accepted: 02/28/2006] [Indexed: 05/09/2023]
Abstract
This study investigates the mechanisms controlling the distribution of 3-bromo-2,2-bis(bromomethyl)propanol (TBNPA) and 2,2-bis(bromomethyl)propan-1,3-diol (DBNPG) in a fractured chalk aquitard. An extensive monitoring program showed a systematic decrease in the TBNPA/DBNPG ratio with distance from the contamination source. Sorption of TBNPA on the white and/or gray chalks comprising the aquitard is approximately one order of magnitude greater than that of DBNPG. This results in more efficient removal of TBNPA from the fracture into the porous matrix and thus decreases the TBNPA/DBNPG ratio in the fracture water. Mathematical modeling of solute transport in the fracture domain illustrates the probable importance of sorption in controlling the spatial variation in TBNPA and DBNPG ratio.
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Affiliation(s)
- Shai Ezra
- Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, Beer Sheva, 84105, Israel.
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