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Dehkordi NR, Knapp M, Compton P, Fernandez LA, Alshawabkeh AN, Larese-Casanova P. Degradation of Dissolved RDX, NQ, and DNAN by Cathodic Processes in an Electrochemical Flow-Through Reactor. JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 2022; 10:107865. [PMID: 37124117 PMCID: PMC10147348 DOI: 10.1016/j.jece.2022.107865] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Both legacy munitions compounds (e.g., RDX) and new insensitive high explosives (e.g. DNAN, NQ) are being manufactured and utilized concurrently, and there exists a need for wastewater treatment systems that are able to degrade both classes of explosives. Electrochemical systems offer treatment possibilities using inexpensive materials and no chemical additions. Electrochemically induced removal of RDX, NQ, and DNAN were separately studied within an electrochemical plug flow reactor hosting a stainless steel (SS) cathode and downstream Ti/MMO anode. Varying wire mesh cathodes and operating conditions were evaluated in an effort to identify the optimal cathode material, to determine the relative contributions of cathodically-induced removal processes, to shorten time to steady-state removal conditions, and to find practical ranges of operating conditions. Applied current allowed the cathode to support munitions removal mainly by direct reduction at the cathode surface, and the secondary reactions of cathodically-induced alkaline hydrolysis and catalytic hydrogenation by adsorbed H on Ni-containing cathode surfaces might contribute to some munitions degradation. The optimal cathode material was identified as SS grade 316, possibly due to its superior Ni content and lack of corrosion protection coating. Higher current, longer cathode length, and smaller mesh pore sizes resulted in slightly greater removal extents and shorter acclimation times to steady state removal conditions, but there are practical upper limits to these properties. Higher Ni content within SS improved RDX and NQ removal but does not affect DNAN removal. Prolonged use of SS grade 316 showed no debilitating changes in electrical performance or chemical content.
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Affiliation(s)
| | | | | | | | | | - Philip Larese-Casanova
- Corresponding Author: Philip Larese-Casanova, Department of Civil & Environmental Engineering, Northeastern University, 400 Snell Engineering, Boston, Massachusetts, 02115, USA, Phone: +1-617-373-2899; Fax: +1-617-373-4419,
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2
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Compton P, Dehkordi NR, Knapp M, Fernandez LA, Alshawabkeh AN, Larese-Casanova P. Heterogeneous Fenton-Like Catalysis of Electrogenerated H2O2 for Dissolved RDX Removal. FRONTIERS IN CHEMICAL ENGINEERING 2022; 4. [DOI: 10.3389/fceng.2022.864816] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
New insensitive high explosives pose great challenges to conventional explosives manufacturing wastewater treatment processes and require advanced methods to effectively and efficiently mineralize these recalcitrant pollutants. Oxidation processes that utilize the fundamental techniques of Fenton chemistry optimized to overcome conventional limitations are vital to provide efficient degradation of these pollutants while maintaining cost-effectiveness and scalability. In this manner, utilizing heterogeneous catalysts and in-situ generated H2O2 to degrade IHEs is proposed. For heterogeneous catalyst optimization, varying the surface chemistry of activated carbon for use as a catalyst removes precipitation complications associated with iron species in Fenton chemistry while including removal by adsorption. Activated carbon impregnated with 5% MnO2 in the presence of H2O2 realized a high concentration of hydroxyl radical formation - 140 μM with 10 mM H2O2 - while maintaining low cost and relative ease of synthesis. This AC-Mn5 catalyst performed effectively over a wide pH range and in the presence of varying H2O2 concentrations with a sufficient effective lifetime. In-situ generation of H2O2 removes the logistical and economic constraints associated with external H2O2, with hydrophobic carbon electrodes utilizing generated gaseous O2 for 2-electron oxygen reduction reactions. In a novel flow-through reactor, gaseous O2 is generated on a titanium/mixed metal oxide anode with subsequent H2O2 electrogeneration on a hydrophobic microporous-layered carbon cloth cathode. This reactor is able to electrogenerate 2 mM H2O2 at an optimized current intensity of 150 mA and over a wide range of flow rates, influent pH values, and through multiple iterations. Coupling these two optimization methods realizes the production of highly oxidative hydroxyl radicals by Fenton-like catalysis of electrogenerated H2O2 on the surface of an MnO2-impregnated activated carbon catalyst. This method incorporates electrochemically induced oxidation of munitions in addition to removal by adsorption while maintaining cost-effectiveness and scalability. It is anticipated this platform holds great promise to eliminate analogous contaminants.
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Lin CJ, Zhang R, Waisner SA, Nawaz T, Center L, Gent DB, Johnson JL, Holland S. Effects of process factors on the performance of electrochemical disinfection for wastewater in a continuous-flow cell reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:36573-36584. [PMID: 33704635 DOI: 10.1007/s11356-021-13193-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
Although electrochemical disinfection has been shown to be an effective approach to inactivate bacteria in saline water, the effects of process parameters and reactor design for its application in low-salinity water have not been well understood. In this study, factorial experiments were performed to investigate the direct and confounded effects of applied current (5-20 mA), contact time (2.5-20 min), anode surface area (185-370 cm2), and chloride concentration (50-400 mg L-1) on the disinfection efficiency in fresh water and the secondary effluent of municipal wastewater. An electrochemical disinfection reactor cell with an internal volume of 75 cm3 was designed and fabricated. Residence time distribution analysis showed that the internal mixing of the reactor is similar to that of a dispersed plug-flow reactor. All studied process parameters showed significant effect on the kill efficiency, with the applied current and contact time having the most dominant effect. Although the effect of chloride concentration, which is responsible for electrochemical production of free chlorine in water, is statistically significant, it is not as prominent as those reported for high salinity water. A synergistic effect between chloride concentration and anode surface area was identified, leading to high kill efficiency (99.9%, 3 log kill) at low current density (0.0135 mA cm-2). Response surface modeling results suggested that a scaled-up disinfection reactor can be designed using large anode surface area with long contact time for high chloride water (400 mg L-1) or high current density with short contact time for low chloride water (50 mg L-1). The power requirement of a portable system treating 37.85 m3 day-1 (10,000 gpd) of municipal wastewater was estimated to be 1.9 to 8.3 kW to achieve a 3 log kill, depending on the reactor design.
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Affiliation(s)
- Che-Jen Lin
- Department of Civil & Environmental Engineering, Lamar University, Beaumont, TX, 77710, USA.
- Center for Advances in Water & Air Quality, Lamar University, Beaumont, TX, 77710, USA.
| | - Ruolin Zhang
- Department of Civil & Environmental Engineering, Lamar University, Beaumont, TX, 77710, USA
| | - Scott A Waisner
- Environmental Laboratory, U.S. Army Engineer Research and Development Center, Vicksburg, MS, 39180, USA
| | - Tabish Nawaz
- Center for Advances in Water & Air Quality, Lamar University, Beaumont, TX, 77710, USA
- Environmental Science and Engineering Department, Indian Institute of Technology Bombay, Powai, Maharashtra, 400076, India
| | - Lori Center
- Texas Research Institute for Environmental Studies, Sam Houston State University, Huntsville, TX, 77341, USA
| | - David B Gent
- Environmental Laboratory, U.S. Army Engineer Research and Development Center, Vicksburg, MS, 39180, USA
| | - Jared L Johnson
- Environmental Laboratory, U.S. Army Engineer Research and Development Center, Vicksburg, MS, 39180, USA
| | - Sabin Holland
- Texas Research Institute for Environmental Studies, Sam Houston State University, Huntsville, TX, 77341, USA
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Mao X, Xiong L, Hu X, Yan Z, Wang L, Xu G. Remediation of ammonia-contaminated groundwater in landfill sites with electrochemical reactive barriers: A bench scale study. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 78:69-78. [PMID: 32559961 DOI: 10.1016/j.wasman.2018.05.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/09/2018] [Accepted: 05/10/2018] [Indexed: 06/11/2023]
Abstract
Leachate plumes originating from leaking landfills often cause the contamination of groundwater in subsurface. Ammonia nitrogen in the contaminated groundwater is usually hard to be attenuated due to the hypoxic condition in subsurface environment. In this study, an active chlorine mediated electrochemical reactive barrier (ACM-ERB) consisting of inert electrodes is proposed for the remediation of ammonia-contaminated groundwater because an elevated level of chloride ions was often found in the groundwater polluted by leachate plumes. Bench-scale experiments were conducted to evaluate the prototype of this remedial technology and to study the variables affecting the performance of ACM-ERB. The results showed that ammonia in the simulated groundwater can be effectively converted into nitrogen rather than undesirable nitrite/nitrate. RuO2/Ti anode was better than PbO2/Ti anode for the sake of ammonia removal. In the presence of naturally occurring level of bicarbonate, the electrode arrangement with an upstream cathode offered weak alkaline pH and therefore favored the removal of ammonia in the initial stage of experiment. Higher current densities and bicarbonate concentrations were favorable to the removal of ammonia. An ammonia removal efficiency up to 70% was achieved for 20 mg/L NH4+-N influent, when the operating conditions were 250 mg/L chloride ions, 500 mA current, -80 mm water level and 6 mL/min flow rate. Polarity reversal could prevent the formation of scale on electrodes, thereby allowing the long-term operation of the ACM-ERB system in groundwater. Moreover, in the experiment using diluted leachate as influent solution, ammonia was preferentially removed relative to the organic contaminants. The present study demonstrates that ACM-ERB is a promising method to cope with the ammonia-contaminated groundwater in landfill sites.
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Affiliation(s)
- Xuhui Mao
- School of Resource and Environmental Sciences, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China.
| | - Lili Xiong
- School of Resource and Environmental Sciences, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Xinyu Hu
- School of Resource and Environmental Sciences, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Zhiping Yan
- School of Resource and Environmental Sciences, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China
| | - Lei Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Gang Xu
- School of Resource and Environmental Sciences, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Wuhan University, Wuhan 430079, China; Technology Transfer Center of Wuhan University in Zhongshan City, Lonkee Membrane Company, Zhongshan 528400, China
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5
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Electrolytic control of hydrogen peroxide release from calcium peroxide in aqueous solution. Electrochem commun 2018; 93:81-85. [PMID: 30542246 DOI: 10.1016/j.elecom.2018.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The in situ generation of hydrogen peroxide (H2O2) for water treatment is more practical than the use of liquid H2O2, which is costly to store and transport. Calcium peroxide (CaO2), a solid carrier of H2O2, can release H2O2 on dissolution in water. However, the constant H2O2 release rate of CaO2 has been a bottleneck constraining its wider application. In this study, a practical electrochemical method using a divided cell is developed to control the rate of release of H2O2 from CaO2. The results show that the rate of H2O2 release from CaO2 is enhanced in the anolyte. The increase in H2O2 release is positively correlated with the current. Under a current of 100 mA, the H2O2 concentration was 2.5 times higher after 30 min of electrolysis than in the control experiment in which no current was applied. Water electrolysis in the anodic compartment generates protons that not only: (i) en-hance dissolution of CaO2 and release of H2O2, but also (ii) neutralize the alkaline pH resulting from CaO2 dissolution, thus providing new advantages for the use of CaO2. This effective technique may be suitable for the sophisticated control of H2O2 release in environmental applications.
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Zhou W, Rajic L, Zhao Y, Gao J, Qin Y, Alshawabkeh AN. Rates of H 2O 2 Electrogeneration by Reduction of Anodic O 2 at RVC Foam Cathodes in Batch and Flow-through Cells. Electrochim Acta 2018; 277:185-196. [PMID: 32153302 DOI: 10.1016/j.electacta.2018.04.174] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The Electro-Fenton process for in-situ H2O2 electrogeneration is impacted by low O2 utilization efficiency (<0.1%) and the need of acid for pH adjustment. An electrochemical flow-through cell can develop localized acidic conditions, coupled with simultaneous formation and utilization of O2 to enhance H2O2 formation. Multiple electrode configurations using reticulated vitreous carbon (RVC) foam and Ti/mixed metal oxides (MMO) are proposed to identify the optimum conditions for H2O2 formation in batch and flow-through cells. A pH of 2.75±0.25 is developed locally in the flow-through cell that supports effective O2 reduction. Up to 9.66 mg/L H2O2 is generated in a 180 mL batch cell under 100 mA, at pH 2, and mixing at 350 rpm. In flow-through conditions, both flow rate and current significantly influence H2O2 production. A current of 120 mA produced 2.27 mg/L H2O2 under a flow rate of 3 mL/min in a 3-electrode cell with one RVC foam cathode at 60 min. The low current of 60 mA does not enable effective H2O2 production, while the high current of 250 mA produced less H2O2 due to parasitic reactions competing with O2 reduction. Higher flow rates decrease the retention time, but also increase the O2 mass transfer. Furthermore, 3-electrode flow-through cell with two RVC foam cathodes was not effective for H2O2 production due to the limited O2 supply for the secondary cathode. Finally, a coupled process that uses both O2 and H2 from water electrolysis is proposed to improve the H2O2 yield further.
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Affiliation(s)
- Wei Zhou
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, P. R. China
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Ljiljana Rajic
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Yuwei Zhao
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Jihui Gao
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, P. R. China
| | - Yukun Qin
- School of Energy Science and Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, P. R. China
| | - Akram N Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
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Chatterjee S, Deb U, Datta S, Walther C, Gupta DK. Common explosives (TNT, RDX, HMX) and their fate in the environment: Emphasizing bioremediation. CHEMOSPHERE 2017; 184:438-451. [PMID: 28618276 DOI: 10.1016/j.chemosphere.2017.06.008] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 05/10/2017] [Accepted: 06/03/2017] [Indexed: 06/07/2023]
Abstract
Explosive materials are energetic substances, when released into the environment, contaminate by posing toxic hazards to environment and biota. Throughout the world, soils are contaminated by such contaminants either due to manufacturing operations, military activities, conflicts of different levels, open burning/open detonation (OB/OD), dumping of munitions etc. Among different forms of chemical explosives, 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro- 1,3,5,7-tetrazocine (HMX) are most common. These explosives are highly toxic as USEPA has recommended restrictions for lifetime contact through drinking water. Although, there are several utilitarian aspects in anthropogenic activities, however, effective remediation of explosives is very important. This review article emphasizes the details of appropriate practices to ameliorate the contamination. Critical evaluation has also been made to encompass the recent knowledge and advancement about bioremediation and phytoremediation of explosives (especially TNT, RDX and HMX) along with the molecular mechanisms of biodegradation.
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Affiliation(s)
- Soumya Chatterjee
- Defence Research Laboratory, DRDO, Post Bag No. 02, Tezpur, 784001, Assam, India
| | - Utsab Deb
- Defence Research Laboratory, DRDO, Post Bag No. 02, Tezpur, 784001, Assam, India
| | - Sibnarayan Datta
- Defence Research Laboratory, DRDO, Post Bag No. 02, Tezpur, 784001, Assam, India
| | - Clemens Walther
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Radioökologie und Strahlenschutz (IRS), Herrenhäuser Str. 2, Gebäude 4113, 30419, Hannover, Germany
| | - Dharmendra K Gupta
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Radioökologie und Strahlenschutz (IRS), Herrenhäuser Str. 2, Gebäude 4113, 30419, Hannover, Germany.
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8
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Rajic L, Fallahpour N, Alshawabkeh AN. Impact of electrode sequence on electrochemical removal of trichloroethylene from aqueous solution. APPLIED CATALYSIS. B, ENVIRONMENTAL 2015; 174-175:427-434. [PMID: 25931774 PMCID: PMC4410430 DOI: 10.1016/j.apcatb.2015.03.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The electrode sequence in a mixed flow-through electrochemical cell is evaluated to improve the hydrodechlorination (HDC) of trichloroethylene (TCE) in aqueous solutions. In a mixed (undivided) electrochemical cell, oxygen generated at the anode competes with the transformation of target contaminants at the cathode. In this study, we evaluate the effect of placing the anode downstream from the cathode and using multiple electrodes to promote TCE reduction. Experiments with a cathode followed by an anode (C→A) and an anode followed by a cathode (A→C) were conducted using mixed metal oxide (MMO) and iron as electrode materials. The TCE removal rates when the anode is placed downstream of the cathode (C→A) were 54% by MMO→MMO, 64% by MMO→Fe and 87% by Fe→MMO sequence. Removal rates when the anode is placed upstream of the cathode (A→C) were 38% by MMO→MMO, 58% by Fe→MMO and 69% by MMO→Fe sequence. Placing the anode downstream of the cathode positively improves (by 26%) the degradation of aqueous TCE in a mixed flow-through cell as it minimizes the influence of oxygen generated at the MMO anode on TCE reduction at the cathode. Furthermore, placing the MMO anode downstream of the cathode neutralizes pH and redox potential of the treated solution. Higher flow velocity under the C→A setup increases TCE mass flux reduction rate. Using multiple cathodes and an iron foam cathode up stream of the anode increase the removal rate by 1.6 and 2.4 times, respectively. More than 99% of TCE was removed in the presence of Pd catalyst on carbon and as an iron foam coating. Enhanced reaction rates found in this study imply that a mixed flow-through electrochemical cell with multiple cathodes up stream of an anode is an effective method to promote the reduction of TCE in groundwater.
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Affiliation(s)
- Ljiljana Rajic
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA 02115, United States
| | - Noushin Fallahpour
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA 02115, United States
| | - Akram N. Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA 02115, United States
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9
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Yan F, Reible D. Electro-bioremediation of contaminated sediment by electrode enhanced capping. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 155:154-61. [PMID: 25819321 PMCID: PMC4500155 DOI: 10.1016/j.jenvman.2015.03.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Revised: 03/03/2015] [Accepted: 03/13/2015] [Indexed: 05/27/2023]
Abstract
In-situ capping often eliminates or slows natural degradation of hydrocarbon due to the reducing conditions in the sediments. The purpose of this research was to demonstrate a reactive capping technique, an electrode enhanced cap, to produce favorable conditions for hydrocarbon degradation and evaluate this reactive capping technique for contaminated sediment remediation. Two graphite electrodes were placed horizontally at different layers in a cap and connected to external power of 2 V. Redox potentials increased and pH decreased around the anode. Phenanthrene concentration decreased and PAH degradation genes increased in the vicinity of the anode. Phenanthrene concentrations at 0-1 cm sediment beneath the anode decreased to ∼50% of initial concentration over ∼70 days, while phenanthrene levels in control reactor kept unchanged. A degradation model of electrode enhanced capping was developed to simulate reaction-diffusion processes, and model results show that a reaction-dominated region was created in the vicinity of the anode. Although the degradation dominated region was thin, transport processes in a sediment cap environment are typically sufficiently slow to allow this layer to serve as a permeable reactive barrier for hydrocarbon decontamination.
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Affiliation(s)
- Fei Yan
- Department of Civil and Environmental Engineering, Rice University, Houston, TX 77005-1892, USA.
| | - Danny Reible
- Department of Civil and Environmental Engineering, Texas Tech University, Lubbock, TX 79409-1023, USA
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10
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Gao G, Zhang Q, Hao Z, Vecitis CD. Carbon nanotube membrane stack for flow-through sequential regenerative electro-Fenton. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2375-83. [PMID: 25602741 DOI: 10.1021/es505679e] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Electro-Fenton is a promising advanced oxidation process for water treatment consisting a series redox reactions. Here, we design and examine an electrochemical filter for sequential electro-Fenton reactions to optimize the treatment process. The carbon nanotube (CNT) membrane stack (thickness ∼ 200 μm) used here consisted of 1) a CNT network cathode for O2 reduction to H2O2, 2) a CNT-COOFe(2+) cathode to chemical reduction H2O2 to (•)OH and HO(-) and to regenerate Fe(2+) in situ, 3) a porous PVDF or PTFE insulating separator, and 4) a CNT filter anode for remaining intermediate oxidation intermediates. The sequential electro-Fenton was compared to individual electrochemical and Fenton process using oxalate, a persistent organic, as a target molecule. Synergism is observed during the sequential electro-Fenton process. For example, when [DO]in = 38 ± 1 mg L(-1), J = 1.6 mL min(-1), neutral pH, and Ecell = 2.89 V, the sequential electro-Fenton oxidation rate was 206.8 ± 6.3 mgC m(-2) h(-1), which is 4-fold greater than the sum of the individual electrochemistry (16.4 ± 3.2 mgC m(-2) h(-1)) and Fenton (33.3 ± 1.3 mgC m(-2) h(-1)) reaction fluxes, and the energy consumption was 45.8 kWh kgTOC(-1). The sequential electro-Fenton was also challenged with the refractory trifluoroacetic acid (TFA) and trichloroacetic acid (TCA), and they can be transferred at a removal rate of 11.3 ± 1.2 and 21.8 ± 1.9 mmol m(-2) h(-1), respectively, with different transformation mechanisms.
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Affiliation(s)
- Guandao Gao
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University , Tianjin 300071, China
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11
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Baek K, Ciblak A, Mao X, Kim EJ, Alshawabkeh A. Iron anode mediated transformation of selenate in sand columns. WATER RESEARCH 2013; 47:6538-45. [PMID: 24035677 PMCID: PMC6886739 DOI: 10.1016/j.watres.2013.08.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 08/09/2013] [Accepted: 08/22/2013] [Indexed: 05/13/2023]
Abstract
Removal of aqueous selenate by iron electrolysis is investigated using sand-packed column experiments under a flowing condition. An iron anode generates ferrous ions, while cathode produces hydroxide, thus producing ferrous hydroxide capable of reducing selenate to elemental selenium. Additionally, siderite could reduce selenate or selenite to elemental selenium. The removal rate of selenate is proportional to the contact time and the yield of ferrous hydroxide or ferrous carbonate. At a sequence of anode-cathode, the transformation of selenate mostly occurs in the zone after cathode. An operation of 48 h electrolysis finally transforms 82.2% of selenate at 0.2 mM of initial concentration, 1.8 m/day of seepage velocity and 1.26 mA/cm(2) of current density. A longer reactive zone after cathode slightly increases the reduction of selenate to 84.1%, in comparison with 82.2% of a shorter residence time in the reactive zone after cathode. With shorter electrode spacing (approximately 27% shorter), the transformation rate of selenate decreased to 73.5%; however, the specific electrical energy consumption was saved by 78%. A sequence of cathode-anode was ineffective in removing selenate because of the lack of reducing agent in the column. The results indicate that the electrochemical system might be effective in removing selenate in a single well.
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Affiliation(s)
- Kitae Baek
- Department of Environmental Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju, Republic of Korea.
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12
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Yuan S, Chen M, Mao X, Alshawabkeh AN. A three-electrode column for Pd-catalytic oxidation of TCE in groundwater with automatic pH-regulation and resistance to reduced sulfur compound foiling. WATER RESEARCH 2013; 47:269-78. [PMID: 23121896 PMCID: PMC3581803 DOI: 10.1016/j.watres.2012.10.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 09/13/2012] [Accepted: 10/04/2012] [Indexed: 05/11/2023]
Abstract
A hybrid electrolysis and Pd-catalytic oxidation process is evaluated for degradation of trichloroethylene (TCE) in groundwater. A three-electrode, one anode and two cathodes, column is employed to automatically develop a low pH condition in the Pd vicinity and a neutral effluent. Simulated groundwater containing up to 5 mM bicarbonate can be acidified to below pH 4 in the Pd vicinity using a total of 60 mA with 20 mA passing through the third electrode. By packing 2 g of Pd/Al(2)O(3) pellets in the developed acidic region, the column efficiency for TCE oxidation in simulated groundwater (5.3 mg/L TCE) increases from 44 to 59 and 68% with increasing Fe(II) concentration from 0 to 5 and 10 mg/L, respectively. Different from Pd-catalytic hydrodechlorination under reducing conditions, this hybrid electrolysis and Pd-catalytic oxidation process is advantageous in controlling the fouling caused by reduced sulfur compounds (RSCs) because the in situ generated reactive oxidizing species, i.e., O(2), H(2)O(2) and OH, can oxidize RSCs to some extent. In particular, sulfite at concentrations less than 1 mM even greatly increases TCE oxidation by the production of SO(4)(•-), a strong oxidizing radical, and more OH.
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Affiliation(s)
- Songhu Yuan
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan, 430074, P. R. China
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
- Corresponding author. (S. Yuan), (A. Alshawabkeh)
| | - Mingjie Chen
- Atmospheric, Earth and Energy Division, Lawrence Livermore National Laboratory, P.O. Box 808, L-184, Livermore, CA 94550, United States
| | - Xuhui Mao
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Akram N. Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
- Corresponding author. (S. Yuan), (A. Alshawabkeh)
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Gent DB, Wani A, Alshawabkeh AN. Experimental Design for One Dimensional Electrolytic Reactive Barrier for Remediation of Munition Constituent in Groundwater. Electrochim Acta 2012; 86:130-137. [PMID: 23472044 DOI: 10.1016/j.electacta.2012.04.043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A combination of direct electrochemical reduction and in-situ alkaline hydrolysis has been proposed to decompose energetic contaminants such as 1,3,5-Trinitroperhydro- 1,3,5-triazine and 2,4,6-Trinitrotoluene (RDX) in deep aquifers. This process utilizes natural groundwater convection to carry hydroxide produced by an upstream cathode to remove the contaminant at the cathode as well as in the pore water downstream as it migrates toward the anode. Laboratory evaluation incorporated fundamental principles of column design coupled with reactive contaminant modeling including electrokinetics transport. Batch and horizontal sand-packed column experiments included both alkaline hydrolysis and electrochemical treatment to determine RDX decomposition reaction rate coefficients. The sand packed columns simulated flow through a contaminated aquifer with a seepage velocity of 30.5 cm/day. Techniques to monitor and record the transient electric potential, hydroxide transport and contaminant concentration within the column were developed. The average reaction rate coefficients for both the alkaline batch (0.0487 hr-1) and sand column (0.0466 hr-1) experiments estimated the distance between the cathode and anode required to decompose 0.5 mg/L RDX to the USEPA drinking water lifetime Health Advisory level of 0.002 mg/L to be 145 and 152 cm.
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Affiliation(s)
- David B Gent
- USACE ERDC EL, 3909 Halls Ferry Road, Vicksburg, MS, U.S.A
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Mao X, Yuan S, Fallahpour N, Ciblak A, Howard J, Padilla I, Loch-Caruso R, Alshawabkeh AN. Electrochemically induced dual reactive barriers for transformation of TCE and mixture of contaminants in groundwater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:12003-11. [PMID: 23067023 PMCID: PMC3493133 DOI: 10.1021/es301711a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
A novel reactive electrochemical flow system consisting of an iron anode and a porous cathode is proposed for the remediation of mixture of contaminants in groundwater. The system consists of a series of sequentially arranged electrodes, a perforated iron anode, a porous copper cathode followed by a mesh-type mixed metal oxide anode. The iron anode generates ferrous species and a chemically reducing environment, the porous cathode provides a reactive electrochemically reducing barrier, and the inert anode provides protons and oxygen to neutralize the system. The redox conditions of the electrolyte flowing through this system can be regulated by controlling the distribution of the electric current. Column experiments are conducted to evaluate the process and study the variables. The electrochemical reduction on a copper foam cathode produced an electrode-based reductive potential capable of reducing TCE and nitrate. Rational electrodes arrangement, longer residence time of electrolytes and higher surface area of the foam electrode improve the reductive transformation of TCE. More than 82.2% TCE removal efficiency is achieved for the case of low influent concentration (<7.5 mg/L) and high current (>45 mA). The ferrous species produced from the iron anode not only enhance the transformation of TCE on the cathode, but also facilitates transformation of other contaminants including dichromate, selenate and arsenite. Removal efficiencies greater than 80% are achieved for these contaminants in flowing contaminated water. The overall system, comprising the electrode-based and electrolyte-based barriers, can be engineered as a versatile and integrated remedial method for a relatively wide spectrum of contaminants and their mixtures.
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Affiliation(s)
- Xuhui Mao
- Civil and Environmental Engineering Department, Northeastern University, Boston, MA, 02115, USA
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, P. R. China
| | - Songhu Yuan
- Civil and Environmental Engineering Department, Northeastern University, Boston, MA, 02115, USA
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, P. R. China
| | - Noushin Fallahpour
- Civil and Environmental Engineering Department, Northeastern University, Boston, MA, 02115, USA
| | - Ali Ciblak
- Civil and Environmental Engineering Department, Northeastern University, Boston, MA, 02115, USA
| | - Joniqua Howard
- Department of Civil Engineering and Surveying, University of Puerto Rico, Mayaguez, Puerto Rico, 00681
| | - Ingrid Padilla
- Department of Civil Engineering and Surveying, University of Puerto Rico, Mayaguez, Puerto Rico, 00681
| | - Rita Loch-Caruso
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan 48109
| | - Akram N. Alshawabkeh
- Civil and Environmental Engineering Department, Northeastern University, Boston, MA, 02115, USA
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Yan F, Reible DD. PAH degradation and redox control in an electrode enhanced sediment cap. JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY (OXFORD, OXFORDSHIRE : 1986) 2012; 87:1222-1228. [PMID: 23329859 PMCID: PMC3544081 DOI: 10.1002/jctb.3767] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Capping is typically used to control contaminant release from the underlying sediments. However, the presence of conventional sediment caps will often eliminate or slow natural degradation that might otherwise occur at the surface sediment. The objective of this study was to explore the potential of a novel reactive capping, an electrode enhanced cap for the remediation of PAH contaminated sediment. The study on electrode enhanced biodegradation of PAH in slurries showed that naphthalene concentration decreased from ~1000 μg/L to ~50 μg/L, and phenanthrene decreased from ~150 μg/L to ~30 μg/L in ElectroBioReactor within 4 days, and the copy numbers of PAH degrading genes increased by almost 2 orders of magnitude. In a cap microcosm, two carbon electrodes were emplaced within a sediment cap with an applied potential of 2 V. The anode was placed at the sediment-cap interface encouraging oxidizing conditions. Oxidation and Reduction Potential (ORP) profiles showed redox potential approximately 60-100 mV higher at the sediment-cap interface with the application of voltage than in controls. Vertical profiles of phenanthrene porewater concentration were obtained by PDMS-coated fiber, and results showed that phenanthrene at the depth of 0-0.5 cm below the anode was degraded to ~70% of the initial concentration within 10 weeks. PAH degrading genes showed an increase of approximately 1 order of magnitude at the same depth. The no power controls showed no degradation of PAH. These findings suggest that electrode enhanced capping can be used to control redox potential, provide microbial electron acceptor, and stimulate PAH degradation.
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Affiliation(s)
- Fei Yan
- Department of Civil, Architectural, Environmental Engineering, The University of Texas at Austin, 1 University Station C1786, Austin, TX 78712-0273, , phone: (512) 471-6682
| | - Danny D. Reible
- Corresponding author. , phone: (512) 471-4642, fax: (512) 471-5870
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Zheng M, Bao J, Liao P, Wang K, Yuan S, Tong M, Long H. Electrogeneration of H(2) for Pd-catalytic hydrodechlorination of 2,4-dichlorophenol in groundwater. CHEMOSPHERE 2012; 87:1097-1104. [PMID: 22377173 DOI: 10.1016/j.chemosphere.2012.01.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 01/30/2012] [Accepted: 01/30/2012] [Indexed: 05/31/2023]
Abstract
A novel electrolytic groundwater remediation process, which used the H(2) continuously generated at cathode to achieve in situ catalytic hydrodechlorination, was developed for the treatment of 2,4-dichlorophenol (2,4-DCP) in groundwater. Catalytic hydrodechlorination using Pd supported on bamboo charcoal and external H(2) showed that 2,4-DCP was completely dechlorinated to phenol within 30 min at pH ≤ 5.5. In a divided electrolytic system, the catalytic hydrodechlorination of 2,4-DCP in cathodic compartment by H(2) generated at the cathode under 20 and 50 mA reached 100% at 120 and 60 min, respectively. Two column experiments with influent pHs of 5.5 (unconditioned) and 2 were conducted to evaluate the feasibility of this process. The 2,4-DCP removal efficiencies were about 63% and nearly 100% at influent pHs of 5.5 and 2, respectively. Phenol was solely produced by 2,4-DCP hydrodechlorination, and was subsequently degraded at the anode. A low pH could enhance the hydrodechlorination, but was not necessarily required. This study provides the preliminary results of a novel effective electrolytic process for the remediation of groundwater contaminated by chlorinated aromatics.
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Affiliation(s)
- Mingming Zheng
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, PR China
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Yuan S, Mao X, Alshawabkeh AN. Efficient degradation of TCE in groundwater using Pd and electro-generated H2 and O2: a shift in pathway from hydrodechlorination to oxidation in the presence of ferrous ions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:3398-405. [PMID: 22315993 PMCID: PMC3319670 DOI: 10.1021/es204546u] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Degradation of trichloroethylene (TCE) in simulated groundwater by Pd and electro-generated H(2) and O(2) is investigated in the absence and presence of Fe(II). In the absence of Fe(II), hydrodechlorination dominates TCE degradation, with accumulation of H(2)O(2) up to 17 mg/L. Under weak acidity, low concentrations of oxidizing •OH radicals are detected due to decomposition of H(2)O(2), slightly contributing to TCE degradation via oxidation. In the presence of Fe(II), the degradation efficiency of TCE at 396 μM improves to 94.9% within 80 min. The product distribution proves that the degradation pathway shifts from 79% hydrodechlorination in the absence of Fe(II) to 84% •OH oxidation in the presence of Fe(II). TCE degradation follows zeroth-order kinetics with rate constants increasing from 2.0 to 4.6 μM/min with increasing initial Fe(II) concentration from 0 to 27.3 mg/L at pH 4. A good correlation between TCE degradation rate constants and •OH generation rate constants confirms that •OH is the predominant reactive species for TCE oxidation. Presence of 10 mM Na(2)SO(4), NaCl, NaNO(3), NaHCO(3), K(2)SO(4), CaSO(4), and MgSO(4) does not significantly influence degradation, but sulfite and sulfide greatly enhance and slightly suppress degradation, respectively. A novel Pd-based electrochemical process is proposed for groundwater remediation.
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Affiliation(s)
- Songhu Yuan
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, 388 Lumo Road, Wuhan, 430074, P. R. China
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Xuhui Mao
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Akram N. Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
- To whom correspondence should be addressed. . Phone: (617) 373-3994
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Ciblak A, Mao X, Padilla I, Vesper D, Alshawabkeh I, Alshawabkeh AN. Electrode effects on temporal changes in electrolyte pH and redox potential for water treatment. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2012; 47:718-26. [PMID: 22416866 PMCID: PMC3329560 DOI: 10.1080/10934529.2012.660088] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The performance of electrochemical remediation methods could be optimized by controlling the physicochemical conditions of the electrochemical redox system. The effects of anode type (reactive or inert), current density and electrolyte composition on the temporal changes in pH and redox potential of the electrolyte were evaluated in divided and mixed electrolytes. Two types of electrodes were used: iron as a reactive electrode and mixed metal oxide coated titanium (MMO) as an inert electrode. Electric currents of 15, 30, 45 and 60 mA (37.5 mA L(-1), 75 mA L(-1), 112.5 mA L(-1) and 150 mA L(-1)) were applied. Solutions of NaCl, Na(2)SO(4) and NaHCO(3) were selected to mimic different wastewater or groundwater compositions. Iron anodes resulted in highly reducing electrolyte conditions compared to inert anodes. Electrolyte pH was dependent on electrode type, electrolyte composition and current density. The pH of mixed-electrolyte was stable when MMO electrodes were used. When iron electrodes were used, the pH of electrolyte with relatively low current density (37.5 mA L(-1)) did not show significant changes but the pH increased sharply for relatively high current density (150 mA L(-1)). Sulfate solution showed more basic and relatively more reducing electrolyte conditions compared to bicarbonate and chloride solution. The study shows that a highly reducing environment could be achieved using iron anodes in divided or mixed electrolytes and the pH and redox potential could be optimized using appropriate current and polarity reversal.
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Affiliation(s)
- Ali Ciblak
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Xuhui Mao
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
| | - Ingrid Padilla
- Department of Civil Engineering and Surveying, University of Puerto Rico, Mayaguez, PR
| | - Dorothy Vesper
- Department of Geology and Geography, West Virginia University, Morgantown, WV, USA
| | | | - Akram N. Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, Boston, MA, USA
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Soils contaminated with explosives: Environmental fate and evaluation of state-of-the-art remediation processes (IUPAC Technical Report). PURE APPL CHEM 2011. [DOI: 10.1351/pac-rep-10-01-05] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An explosion occurs when a large amount of energy is suddenly released. This energy may come from an over-pressurized steam boiler, from the products of a chemical reaction involving explosive materials, or from a nuclear reaction that is uncontrolled. In order for an explosion to occur, there must be a local accumulation of energy at the site of the explosion, which is suddenly released. This release of energy can be dissipated as blast waves, propulsion of debris, or by the emission of thermal and ionizing radiation. Modern explosives or energetic materials are nitrogen-containing organic compounds with the potential for self-oxidation to small gaseous molecules (N2, H2O, and CO2). Explosives are classified as primary or secondary based on their susceptibility of initiation. Primary explosives are highly susceptible to initiation and are often used to ignite secondary explosives, such as TNT (2,4,6-trinitrotoluene), RDX (1,3,5-trinitroperhydro-1,3,5-triazine), HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane), and tetryl (N-methyl-N-2,4,6-tetranitro-aniline).
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Sun M, Yan F, Zhang R, Reible DD, Lowry GV, Gregory KB. Redox control and hydrogen production in sediment caps using carbon cloth electrodes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:8209-8215. [PMID: 20879761 PMCID: PMC2989605 DOI: 10.1021/es101003j] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Sediment caps that degrade contaminants can improve their ability to contain contaminants relative to sand and sorbent-amended caps, but few methods to enhance contaminant degradation in sediment caps are available. The objective of this study was to determine if, carbon electrodes emplaced within a sediment cap at poised potential could create a redox gradient and provide electron donor for the potential degradation of contaminants. In a simulated sediment cap overlying sediment from the Anacostia River (Washington, DC), electrochemically induced redox gradients were developed within 3 days and maintained over the period of the test (∼100 days). Hydrogen and oxygen were produced by water electrolysis at the electrode surfaces and may serve as electron donor and acceptor for contaminant degradation. Electrochemical and geochemical factors that may influence hydrogen production were studied. Hydrogen production displayed zero order kinetics with ∼75% Coulombic efficiency. Rates were proportional to the applied potential between 2.5 and 5 V and not greatly affected by pH. Hydrogen production was promoted by increasing ionic strength and in the presence of natural organic matter. Carbon electrode-stimulated degradation of tetrachlorobenzene in a batch reactor was dependent on applied voltage and production of hydrogen to a concentration above the threshold for biological dechlorination. These findings suggest that electrochemical reactive capping can potentially be used to create "reactive" sediments caps capable of promoting chemical or biological transformations of contaminants within the cap.
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Affiliation(s)
- Mei Sun
- Department of Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890, USA
| | - Fei Yan
- Environmental & Water Resources Engineering, University of Texas, Austin, TX 78712
| | - Ruiling Zhang
- Environmental & Water Resources Engineering, University of Texas, Austin, TX 78712
| | - Danny D. Reible
- Environmental & Water Resources Engineering, University of Texas, Austin, TX 78712
| | - Gregory V. Lowry
- Department of Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890, USA
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890, USA
| | - Kelvin B. Gregory
- Department of Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890, USA
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