Treatment methods for the remediation of nitroaromatic explosives.

Application of advanced oxidation processes for TNT removal: A review.

Energetic materials comprise both explosives and propellants. When released to the biosphere, energetics are xenobiotic contaminants which pose toxic hazards to ecosystems, humans, and other biota. Soils worldwide are contaminated by energetic materials from manufacturing operations; military conflict; military training activities at firing and impact ranges; and open burning/open detonation (OB/OD) of obsolete munitions. Energetic materials undergo varying degrees of chemical and biochemical transformation depending on the compounds involved and environmental factors. This paper addresses the occurrence of energetic materials in soils including a discussion of their fates after contact with soil. Emphasis is placed on the 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), and the propellant ingredients nitroglycerin (NG), nitroguanidine (NQ), nitrocellulose (NC), 2,4-dinitrotoluene (2,4-DNT), and perchlorate.

https://downloads.hindawi.com/journals/aess/2012/617236.pdf

Distribution and Fate of Military Explosives and Propellants in Soil: A Review

Treatment of perchlorate in drinking water: A critical review

Adsorption of phenol and 4-nitrophenol on granular activated carbon in basal salt medium: equilibrium and kinetics.

Continuous-flow anaerobic fluidized-bed granular activated carbon bioreactors were used to treat 2,4-dinitrotoluene (2,4-DNT), a compound used in primary propellant production. A synthetic wastewater solution containing 2,4-DNT, ethanol, mineral ether, and a carbonate buffer and another solution containing growth nutrients and vitamins were fed to each of the two bioreactors. The influent ethanol concentrations were varied to determine the effect of ethanol concentration on the extent of 2,4-DNT degradation. The anaerobic bioreactors, when operated under methanogenic conditions with a primary substrate, were able to transform the 2.4-DNT into 2-amino-4-nitrotoluene (2-A-4-NT). 4-amino-2-nitrotoluene (4-A-2-NT), 2,4-diaminotoluene (2,4-DAT), and trace amounts of toluene. During stable operation, for the range of non-zero influent ethanol concentrations evaluated in this study, the majority of the products were identified as 2,4-DAT. Batch activated sludge reactors were used to examine the fate of 2,4-DAT under aerobic conditions. 2,4-DAT (16 mg/L) were mineralized within 9 hours, indicating that a two-stage system may be an effective 2,4-DNT treatment strategy.

Treatment of 2,4-dinitrotoluene using a two-stage system: Fluidized-bed anaerobic grangular activated carbon reactors and aerobic activated sludge reactors

The impact of the presence of molecular oxygen on multicomponent adsorption is evaluated in this study. Adsorption equilibria for binary mixtures of phenol/o‐cresol and ternary mixtures of phenol/o‐cresol/3‐ethylphenol on granular activated carbon (GAC) are determined at 23°C using three different initial‐concentration combinations. Experiments were conducted under conditions where molecular oxygen is present (oxic adsorption) and under conditions where oxygen was excluded from the adsorbate solution and the GAC particles (anoxic adsorption). The ideal adsorbed solution theory, using the Myers equation for correlating the single‐solute anoxic isotherms, is found to accurately describe the competitive adsorption behavior of these phenolic mixtures under anoxic conditions. When the Freundlich equation was used to describe the single solute behavior, increased deviations were observed. Poor model predictions for the oxic isotherms are attributed to the presence of molecular oxygen, which promotes the polymer...

Competitive Adsorption of Phenols on GAC. I: Adsorption Equilibrium

https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1035&context=usarmyresearch

Anaerobic treatment of army ammunition production wastewater containing perchlorate and RDX.

An effective use of the wet air oxidation (WAO) process at a temperature of 340°C and 0.8 MPa P O2(25°C) to treat diluted trinitrotoluene (TNT) red water was previously demonstrated. This study presents the results of a 1-hour WAO of red water at temperatures ranging from 200° to 320°C, and P O2 from 0.13 to 1.31 MPa, in terms of contaminant reduction and intermediate appearance. Also, comparison is made between the toxicity of the raw and the WAO-treated red water on two biological systems. Results show the WAO removal efficiency to be a function primarily of temperature and, to a lesser extent, of P O2 . Acetic acid and 1,3-dinitrobenzene (DNB) accumulated at lower temperatures

Wet air oxidation of trinitrotoluene manufacturing red water

2,4,6-Trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) are major constituents of munitions production wastewater discharged from explosive manufacturing units and munitions load, assembly, and pack operations. Experiments were carried out to study the electrochemical reduction of DNT and a mixture of TNT and RDX. The effect of various parameters including current, stir rate, and presence and absence of dissolved oxygen was investigated. Experiments were conducted using glassy carbon rods as the cathode and platinum wire as the anode. End products were also analyzed for the experiments to obtain molar balance closure for the conversion of the nitroaromatic to intermediates. The experimental results showed that the electrochemical reduction of nitroaromatics follow pseudo first-order rate kinetics. The first-order rate constants for the reduction of nitroaromatics were observed to increase with an increase in current or stir rate. The rate of reduction of th...

Stephen W. Maloney

Papers

Treatment of 2,4-dinitrotoluene using a two-stage system: Fluidized-bed anaerobic grangular activated carbon reactors and aerobic activated sludge reactors

Competitive Adsorption of Phenols on GAC. I: Adsorption Equilibrium

Anaerobic treatment of army ammunition production wastewater containing perchlorate and RDX.

Wet air oxidation of trinitrotoluene manufacturing red water

Electrochemical Reduction of Simulated Munitions Wastewater in a Bench-Scale Batch Reactor