Decomposition of nitro constituents by Fenton process

• Main Authors: Wen-Lung Hsiao, 蕭文隆
• Other Authors: Jin-Lian Tsai
• Format: Others
• Language: en_US
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/96306503546743487263

碩士 === 高雄醫學大學 === 職業安全衛生研究所碩士班 === 92 === Abstract TNT、RDX and HMX are energetic compounds and are polynitro organic explosives. TNT is a nitroaromatic compound, and RDX or HMX is heterocyclic nitramine. TNT was plentyly used in World War Ⅰ. RDX and HMX were developed after World War Ⅱ. They are important explosives used by the US and European munitions industry. TNT is regard as the most important military explosive since World War Ⅰ. Both RDX and HMX are more energetic and stable than TNT, and have been used in both conventional and nuclear weapons. However, these explosives are known to be toxic to aquatic and terrestrial organism. The US EPA classifies TNT and RDX as a psssible carcinogen (class C). HMX has been classified as class D carcinogen . Comtamationin of water and soil by TNT、RDX and HMX is widespread and often caused by various military activities (such as manufacturing, testing and training, demilitarization, open burning/open detonation（OB/OD）) that are considered important for military operations. The object of this research is to use Fenton process to destroy TNT、RDX and HMX in aqueous solution. The Fenton process is recognized as one of the most powerful advanced oxidation technologies available and can be used to destroy a variety of explosive ammunition residues in water and soil. This process can produce hydroxyl radial（•OH） to oxidize many kinds of organic compounds. Fenton oxidations of explosives have been widely investigated, indicating that Fenton reaction could be effective process for the degradation of explosives. Therefore this study used Fenton process to oxidize nitro aromatic and hetercyclic nitramine in order to explore their oxidation efficiencies by the formation of nitrate（NO3－） molar yields. Because the nitrate was converted from nitrite （NO2－） in this reaction, we evaluated the decomposition efficiencies of TNT 、RDX and HMX by the revovery of the nitro groups. The evaluating method is different from the one by the disappear of target compounds. In other words, we explored the target compound：Fe2＋：H2O2 molar ratio by the formation of nitrate（NO3－）molar yields that is in the oxidation reactions of Fenton process. After performing these experiments, we observed the decomposition efficiencies were affected by the pH value, concentration of ferrous ion and hydrogen peroxide, and amount of •OH. Oxidation of TNT, RDX and HMX using Fenton’ reagent proceeded effectively at pH 2.5. At an target：Fe2＋：H2O2 molar ratio of 1：23：1818, TNT was completely removed in 4 to 5 hours. RDX was completely removed at the molar ratio of 1：22：2000 in 7 to 8 hours. However, 47﹪of HMX was at best removed in the experiment, which was at the molar ratio of 1：38：5029 in 9 to 10 hours.