Xu Xiang-Rong, Zhao Zhen-Ye, Li Xiao-Yan, Gu Ji-Dong
Laboratory of Environmental Toxicology, Department of Ecology & Biodiversity, The University of Hong Kong, Pokfulam Road, SAR, Hong Kong, People's Republic of China.
Chemosphere. 2004 Apr;55(1):73-9. doi: 10.1016/j.chemosphere.2003.11.017.
Degradation of methyl tert-butyl ether (MTBE) in aqueous solution by Fenton's reagent (Fe2+ and H2O2) was investigated. Effects of reaction conditions on the oxidation efficiency of MTBE by Fenton's reagent were examined in batch experiments. Under optimum conditions, 15 mM H2O2, 2 mM Fe2+, pH 2.8 and room temperature, the initial 1 mM MTBE solution was reduced by 99% within 120 min. Results showed that MTBE was decomposed in a two-stage reaction. MTBE was first decomposed swiftly based on a Fe2+/H2O2 reaction and then decomposed somewhat less rapidly based on a Fe3+/H2O2 reaction. The detection of Fe2+ also supported the theory of the two-stage reaction for the oxidation of MTBE by Fenton's reagent. The dissolved oxygen in the solution decreased rapidly in the first stage reaction, but it showed a slow increase in the second stage with a zero-order kinetics. A reaction mechanism involving two different pathways for the decomposition of MTBE by Fenton's reagent was also proposed. Chemicals including tert-butyl formate, tert-butyl alcohol, methyl acetate and acetone were identified to be the primary intermediates and by-products of the degradation processes.
研究了芬顿试剂（Fe²⁺和H₂O₂）对甲基叔丁基醚（MTBE）在水溶液中的降解情况。通过批次实验考察了反应条件对芬顿试剂氧化MTBE效率的影响。在最佳条件下，即15 mM H₂O₂、2 mM Fe²⁺、pH 2.8和室温，初始浓度为1 mM的MTBE溶液在120分钟内降解了99%。结果表明，MTBE的分解分两个阶段进行。MTBE首先基于Fe²⁺/H₂O₂反应迅速分解，然后基于Fe³⁺/H₂O₂反应分解速度稍慢。Fe²⁺的检测也支持了芬顿试剂氧化MTBE的两阶段反应理论。溶液中的溶解氧在第一阶段反应中迅速下降，但在第二阶段以零级动力学缓慢增加。还提出了一种涉及芬顿试剂分解MTBE的两种不同途径的反应机理。甲酸叔丁酯、叔丁醇、乙酸甲酯和丙酮等化学物质被确定为降解过程的主要中间体和副产物。
