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Lease N, Klamborowski LM, Perriot R, Cawkwell MJ, Manner VW. Identifying the Molecular Properties that Drive Explosive Sensitivity in a Series of Nitrate Esters. J Phys Chem Lett 2022; 13:9422-9428. [PMID: 36191261 PMCID: PMC9575148 DOI: 10.1021/acs.jpclett.2c02701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Energetic materials undergo hundreds of chemical reactions during exothermic runaway, generally beginning with the breaking of the weakest chemical bond, the "trigger linkage." Herein we report the syntheses of a series of pentaerythritol tetranitrate (PETN) derivatives in which the energetic nitrate ester groups are systematically substituted by hydroxyl groups. Because all the PETN derivatives have the same nitrate ester-based trigger linkages, quantum molecular dynamics (QMD) simulations show very similar Arrhenius kinetics for the first reactions. However, handling sensitivity testing conducted using drop weight impact indicates that sensitivity decreases precipitously as nitrate esters are replaced by hydroxyl groups. These experimental results are supported by QMD simulations that show systematic decreases in the final temperatures of the products and the energy release as the nitrate ester functional groups are removed. To better interpret these results, we derive a simple model based only on the specific enthalpy of explosion and the kinetics of trigger linkage rupture that accounts qualitatively for the decrease in sensitivity as nitrate ester groups are removed.
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Affiliation(s)
- Nicholas Lease
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico87545, United States
| | - Lisa M. Klamborowski
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico87545, United States
| | - Romain Perriot
- Theoretical
Division, Los Alamos National Laboratory, Los Alamos, New Mexico87545, United States
| | - Marc J. Cawkwell
- Theoretical
Division, Los Alamos National Laboratory, Los Alamos, New Mexico87545, United States
| | - Virginia W. Manner
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico87545, United States
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2
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Manner VW, Smilowitz L, Freye CE, Cleveland AH, Brown GW, Suvorova N, Tian H. Chemical Evaluation and Performance Characterization of Pentaerythritol Tetranitrate (PETN) under Melt Conditions. ACS MATERIALS AU 2022; 2:464-473. [PMID: 36855707 PMCID: PMC9928408 DOI: 10.1021/acsmaterialsau.2c00022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pentaerythritol tetranitrate (PETN) is a nitrate ester explosive commonly used in commercial detonators. Although its degradation properties have been studied extensively, very little information has been collected on its thermal stability in the molten state due to the fact that its melting point is only ∼20 °C below its onset of decomposition. Furthermore, studies that have been performed on PETN thermal degradation often do not fully characterize or quantify the decomposition products. In this study, we heat PETN to melt temperatures and identify thermal decomposition products, morphology changes, and mass loss by ultrahigh-pressure liquid chromatography coupled to quadrupole time of flight mass spectrometry, scanning electron microscopy, nuclear magnetic resonance spectroscopy, and differential scanning calorimetry. For the first time, we quantify several decomposition products using independently prepared standards and establish the resulting melting point depression after the first melt. We also estimate the amount of decomposition relative to sublimation that we measure through gas evolution and evaluate the performance behavior of the molten material in commercial detonator configurations.
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Affiliation(s)
- Virginia W. Manner
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico 87544, United States,
| | - Laura Smilowitz
- Physical
Chemistry and Spectroscopy, Los Alamos National
Laboratory, Los Alamos, New Mexico 87544, United States
| | - Chris E. Freye
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
| | - Alexander H. Cleveland
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
| | - Geoffrey W. Brown
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
| | - Natalya Suvorova
- Physical
Chemistry and Spectroscopy, Los Alamos National
Laboratory, Los Alamos, New Mexico 87544, United States
| | - Hongzhao Tian
- High
Explosives Science & Technology, Los
Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
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Kumar A, Sahoo SC, Mehta SK, Soni P, Sharma V, Kataria R. A luminescent Zn-MOF for the detection of explosives and development of fingerprints. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2022; 14:700-707. [PMID: 35099486 DOI: 10.1039/d1ay01977e] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A luminescent 3D metal-organic framework [Zn(NDA)(AMP)] = PUC1 (where, NDA = naphthalene-2,6-dicarboxylic acid and AMP = 4-aminomethyl pyridine) was synthesized under solvothermal conditions. The synthesized 3D framework was fully characterized with the help of different analytical techniques such as SCXRD, FTIR, TGA, PXRD, SEM, BET, etc. PUC1 exhibited a strong emission peak at 371 nm when excited at 290 nm and the resulting emission was efficiently quenched in the presence of various organic explosive substances like pentaerythritol tetranitrate (PETN), 2,4,6-trinitrophenyl-N-methylnitramine (Tetryl), trinitrotoluene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and 1,3,5,7-tetranitro-1,3,5,7-tetrazoctane (HMX). PUC1 revealed highly sensitive and selective detection of PETN and Tetryl with high quenching constant values of 0.1 × 106 and 0.12 × 105 M-1 and low detection limits of 0.315 and 0.404 μM respectively. The strong luminescent properties of PUC1 lead to its successful application in the development of latent fingermarks on different non-porous surfaces using the powder dusting method. The accuracy and applicability of the synthesized material were determined by developing fingerprints by using secretions from eccrine and apocrine glands on a glass slide and various other surfaces, followed by dusting the surfaces. The results so obtained were found to be very accurate and promising.
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Affiliation(s)
- Ajay Kumar
- Department of Chemistry, Panjab University, Chandigarh 160014, India.
| | | | | | - Parmod Soni
- Department of Chemistry, Terminal Ballistics Research Laboratory (TBRL), Defence Research and Development Organisation, Chandigarh 160003, India
| | - Vishal Sharma
- Institute of Forensic Science & Criminology, Panjab University, Chandigarh 160014, India.
| | - Ramesh Kataria
- Department of Chemistry, Panjab University, Chandigarh 160014, India.
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4
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Zheng CW, Long M, Luo YH, Long X, Bi Y, Zhou D, Zhou C, Rittmann BE. Reductive destruction of multiple nitrated energetics over palladium nanoparticles in the H 2-based membrane catalyst-film reactor (MCfR). JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127055. [PMID: 34523494 DOI: 10.1016/j.jhazmat.2021.127055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 07/31/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
Nitrated energetics are widespread contaminants due to their improper disposal from ammunition facilities. Different classes of nitrated energetics commonly co-exist in ammunition wastewater, but co-removal of the classes has hardly been documented. In this study, we evaluated the catalytic destruction of three types of energetics using palladium (Pd0) nano-catalysts deposited on H2-transfer membranes in membrane catalyst-film reactors (MCfRs). This work documented nitro-reduction of 2,4,6-trinitrotoluene (TNT), as well as, for the first time, denitration of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and pentaerythritol tetranitrate (PETN) over Pd0 at ambient temperature. The catalyst-specific activity was 20- to 90-fold higher than reported for other catalyst systems. Nitrite (NO2-) released from RDX and PETN also was catalytically reduced to dinitrogen gas (N2). Continuous treatment of a synthetic wastewater containing TNT, RDX, and PETN (5 mg/L each) for more than 20 hydraulic retention times yielded removals higher than 96% for all three energetics. Furthermore, the concentrations of NO2- and NH4+ were below the detection limit due to subsequent NO2- reduction with > 99% selectivity to N2. Thus, the MCfR provides a promising strategy for sustainable catalytic removal of co-existing energetics in ammunition wastewater.
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Affiliation(s)
- Chen-Wei Zheng
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA
| | - Min Long
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA
| | - Yi-Hao Luo
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA
| | - Xiangxing Long
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA; Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, Arizona State University, Tempe, AZ, USA
| | - Yuqiang Bi
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA; Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, Arizona State University, Tempe, AZ, USA
| | - Dandan Zhou
- Engineering Lab for Water Pollution Control and Resources Recovery of Jilin Province, School of Environment, Northeast Normal University, Changchun, China
| | - Chen Zhou
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA.
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ, USA
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5
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Sheven DG, Pervukhin VV. Acceleration of the thermal degradation of PETN in the microdroplets flow reactor. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126670. [PMID: 34329107 DOI: 10.1016/j.jhazmat.2021.126670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
Thermal degradation of pentaerythritol tetranitrate (PETN) was investigated in microdroplets within a heated capillary used as a flow reactor. The thermal degradation was monitored by aerodynamic thermal breakup droplet ionization mass spectrometry. It was shown that the PETN degradation in microdroplets occurs much faster than the bulk reaction (by 4-5 orders of magnitude). The effect of the capillary material [stainless steel (Fe, Cr), copper (Cu), or fused quartz (SiO2)] on the thermal PETN degradation in microdroplets of water or acetonitrile was studied next. The capillary material affected the rate of thermal PETN degradation much more weakly than did the use of microdroplets (pure Cu was most conducive to the degradation). Kinetic parameters (activation energy and the frequency factor) of the PETN degradation for all the studied materials of the flow-through reactor and the solvents were estimated under the assumption that the thermal degradation is a first-order reaction. Implications of the acceleration of PETN degradation in microdroplets are discussed.
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Affiliation(s)
- Dmitriy G Sheven
- Nikolaev Institute of Inorganic Chemistry of SB RAS, Acad. Lavrentieva Ave., 3, 630090 Novosibirsk, Russia.
| | - Viktor V Pervukhin
- Nikolaev Institute of Inorganic Chemistry of SB RAS, Acad. Lavrentieva Ave., 3, 630090 Novosibirsk, Russia
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Sadani M, Karami MA, Teimouri F, Amin MM, Moosavi SM, Dehdashti B. Kinetic parameters and nitrate, nitrite changes in bioremediation of Toxic Pentaerythritol Tetranitrate (PETN) contaminated soil. Electron Physician 2017; 9:5623-5630. [PMID: 29238507 PMCID: PMC5718871 DOI: 10.19082/5623] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 01/18/2017] [Indexed: 11/20/2022] Open
Abstract
Background Cleanup of areas contaminated by explosives is a public health concern. Some explosives can be carcinogenic in humans. Pentaerythritol Tetranitrate (PETN), a powerful explosive with very low water solubility, can be easily transported to ground waters. Objective This study was conducted to determine the removal efficiencies of PETN from soil by bioremediation, and obtain kinetic parameters of biological process. Methods This experimental study was conducted at the Environmental Health Engineering Lab (Isfahan University of Medical Sciences, Isfahan, Iran) in 2015–2016. In the present work, bioremediation of the explosive-polluted soils by PETN in anaerobic-aerobic landfarming method was performed. The influence of seeding and biosurfactant addition on bioremediation was also evaluated. The data were analyzed using Microsoft Excel software. Results The results show that, as the initial concentration of PETN increased, the lag phase was increased and the specific growth rate was increased up to 0.1/day in concentration of 50 mg/kg, and then it was decreased to 0.04/day. Subsequent decreases in specific growth rate can cause substrate inhibition. Seeding causes decrease in lag phase significantly. Biosurfactant addition had little to no impact on the length of lag phase, but biosurfactant plus seeding can increase the growth rate to 0.2/day, however, inhibitory effect of the initial concentration was started in very high concentration of PETN (150 mg/kg). Conclusion Biosurfactant addition and seeding together have an impressive effect on biodegradation of PETN, furthermore seeding can enhance active microbial consortium and biosurfactant can improve the poor aqueous solubility of PETN, therefore making the substrate more accessible.
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Affiliation(s)
- Mohsen Sadani
- Department of Environmental Health Engineering, School of Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Department of Environmental Health Engineering, Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Amin Karami
- Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Department of Environmental Health Engineering, Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.,Department of Environmental Health Engineering, School of Health, Lorestan University of Medical Sciences, Khoramabad, Iran
| | - Fahimeh Teimouri
- Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Department of Environmental Health Engineering, Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.,Department of Environmental Health Engineering, School of Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Mohammad Mehdi Amin
- Ph.D. of Environmental Health, Professor, Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran, and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Bahare Dehdashti
- Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran, and Department of Environmental Health Engineering, Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
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7
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Tso CP, Shih YH. The transformation of hexabromocyclododecane using zerovalent iron nanoparticle aggregates. JOURNAL OF HAZARDOUS MATERIALS 2014; 277:76-83. [PMID: 24962054 DOI: 10.1016/j.jhazmat.2014.04.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 01/02/2014] [Accepted: 04/19/2014] [Indexed: 06/03/2023]
Abstract
Hexabromocyclododecane (HBCD), an emerging contaminant, is a brominated flame retardant that has been widely detected in the environment. In this study, nanoscale zerovalent iron (NZVI) aggregates are firstly used to treat HBCD and its removal under different geochemical conditions is evaluated. HBCD is almost removed from solutions by NZVI, with a kSA of 4.22×10(-3)Lm(-2)min(-1). An increase in the iron dosage and temperature increases the removal rate. The activation energy for the removal of HBCD by NZVI is 30.2kJmol(-1), which suggests that a surface-chemical reaction occurs on NZVI. HBCD is adsorbed on the NZVI surface, where electrons were transferred to HBCD, and consequently forms byproducts with less bromide. Three common groundwater anions decrease the reaction kinetics and efficiency of NZVI. The kobs of HBCD in the presence of anions is in the order: pure water >Cl(-)>NO3(-)≒HCO3(-). The inhibitory effect of these anions may be a result of the possible complexation of anions with the oxidized iron surface. The oxidized sites on NZVI and oxidized species of iron also contribute to the removal of HBCD by adsorption on NZVI from solutions.
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Affiliation(s)
- Chih-ping Tso
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan, ROC
| | - Yang-hsin Shih
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 106, Taiwan, ROC.
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8
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Zhuang L, Gui L, Gillham RW, Landis RC. Laboratory and pilot-scale bioremediation of pentaerythritol tetranitrate (PETN) contaminated soil. JOURNAL OF HAZARDOUS MATERIALS 2014; 264:261-268. [PMID: 24316800 DOI: 10.1016/j.jhazmat.2013.11.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 10/31/2013] [Accepted: 11/14/2013] [Indexed: 06/02/2023]
Abstract
PETN (pentaerythritol tetranitrate), a munitions constituent, is commonly encountered in munitions-contaminated soils, and pose a serious threat to aquatic organisms. This study investigated anaerobic remediation of PETN-contaminated soil at a site near Denver Colorado. Both granular iron and organic carbon amendments were used in both laboratory and pilot-scale tests. The laboratory results showed that, with various organic carbon amendments, PETN at initial concentrations of between 4500 and 5000mg/kg was effectively removed within 84 days. In the field trial, after a test period of 446 days, PETN mass removal of up to 53,071mg/kg of PETN (80%) was achieved with an organic carbon amendment (DARAMEND) of 4% by weight. In previous laboratory studies, granular iron has shown to be highly effective in degrading PETN. However, for both the laboratory and pilot-scale tests, granular iron was proven to be ineffective. This was a consequence of passivation of the iron surfaces caused by the very high concentrations of nitrate in the contaminated soil. This study indicated that low concentration of organic carbon was a key factor limiting bioremediation of PETN in the contaminated soil. Furthermore, the addition of organic carbon amendments such as the DARAMEND materials or brewers grain, proved to be highly effective in stimulating the biodegradation of PETN and could provide the basis for full-scale remediation of PETN-contaminated sites.
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Affiliation(s)
- Li Zhuang
- Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou 510650, China.
| | - Lai Gui
- Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada; Pest Management and Regulatory Agency, Health Canada, Ottawa, Ontario K1A 0K9, Canada
| | - Robert W Gillham
- Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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9
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Brust H, van Asten A, Koeberg M, van der Heijden A, Kuijpers CJ, Schoenmakers P. Pentaerythritol tetranitrate (PETN) profiling in post-explosion residues to constitute evidence of crime-scene presence. Forensic Sci Int 2013; 230:37-45. [PMID: 23622790 DOI: 10.1016/j.forsciint.2013.03.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 03/13/2013] [Accepted: 03/22/2013] [Indexed: 11/28/2022]
Abstract
Pentaerythritol tetranitrate (PETN) and its degradation products are analyzed to discriminate between residues originating from PETN explosions and residues obtained under other circumstances, such as natural degradation on textile, or after handling intact PETN. The degradation products observed in post-explosion samples were identified using liquid chromatography-mass spectrometry as the less-nitrated analogues of PETN: pentaerythritol trinitrate (PETriN), pentaerythritol dinitrate (PEDiN) and pentaerythritol mononitrate (PEMN). Significant levels of these degradation products were observed in post-explosion samples, whereas only very low levels were detected in a variety of intact PETN samples and naturally degraded PETN. No significant degradation was observed after 12 weeks of storage at room temperature and the influence of high relative humidity (90%) was found to be small. Natural degradation was accelerated by storage of small amounts of PETN on different types of textile, resembling the clothing of a suspect, at elevated temperature (333K). This resulted in significant levels of PETN degradation products, but the relative amounts remained much lower than in post-explosion PETN. For PETriN the peak area relative to PETN was 0.014 (SD=0.0051) and 0.39 (SD=0.19) respectively. Based on the peak areas of PETriN, PEDiN and PEMN relative to PETN, it was possible to fully distinguish the post-explosion profiles from the profiles obtained from intact PETN or after (accelerated) natural degradation. Although more data are required to accurately assess the strength of the evidence, this work illustrates that PETN profiling may yield valuable evidence when investigating a possible link between a suspect and post-explosion PETN found on a crime scene. Due to the substantial variation in the degradation pattern between explosion experiments and even between sampling positions in one experiment, the method is not able to distinguish different PETN explosion events.
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Affiliation(s)
- Hanneke Brust
- University of Amsterdam, van 't Hoff Institute for Molecular Sciences, PO Box 94157, 1090 GD Amsterdam, The Netherlands.
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Zhuang L, Gui L, Gillham RW. Biodegradation of pentaerythritol tetranitrate (PETN) by anaerobic consortia from a contaminated site. CHEMOSPHERE 2012; 89:810-816. [PMID: 22647196 DOI: 10.1016/j.chemosphere.2012.04.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 04/23/2012] [Accepted: 04/30/2012] [Indexed: 06/01/2023]
Abstract
This study examined the role of denitrifying and sulfate-reducing bacteria in biodegradation of pentaerythritol tetranitrate (PETN). Microbial inocula were obtained from a PETN-contaminated soil. PETN degradation was evaluated using nitrate and/or sulfate as electron acceptors and acetate as a carbon source. Results showed that under different electron acceptor conditions tested, PETN was sequentially reduced to pentaerythritol via the intermediary formation of tri-, di- and mononitrate pentaerythritol (PETriN, PEDN and PEMN). The addition of nitrate enhanced the degradation rate of PETN by stimulating greater microbial activity and growth of nitrite reducing bacteria that were responsible for degrading PETN. However, a high concentration of nitrite (350mgL(-1)) accumulated from nitrate reduction, consequently caused self-inhibition and temporarily delayed PETN biodegradation. In contrast, PETN degraded at very similar rates in the presence and absence of sulfate, while PETN inhibited sulfate reduction. It is apparent that denitrifying bacteria possessing nitrite reductase were capable of using PETN and its intermediates as terminal electron acceptors in a preferential utilization sequence of PETN, PETriN, PEDN and PEMN, while sulfate-reducing bacteria were not involved in PETN biodegradation. This study demonstrated that under anaerobic conditions and with sufficient carbon source, PETN can be effectively biotransformed by indigenous denitrifying bacteria, providing a viable means of treatment for PETN-containing wastewaters and PETN-contaminated soils.
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Affiliation(s)
- Li Zhuang
- Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou, China.
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Shih YH, Hsu CY, Su YF. Reduction of hexachlorobenzene by nanoscale zero-valent iron: Kinetics, pH effect, and degradation mechanism. Sep Purif Technol 2011. [DOI: 10.1016/j.seppur.2010.10.015] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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