不同价态铁对硝基苯的厌氧降解及影响因素

以硝基苯厌氧降解为考察对象,研究了Fe0/Fe2+/Fe3+对硝基苯的降解,并探讨了初始硝基苯质量浓度、pH值及葡萄糖质量浓度等对硝基苯降解的影响.结果表明,硝基苯厌氧降解主要生成苯胺,显著提高了其生化可降解性;硝基苯在初始pH=6的厌氧污泥体系中可被完全降解,不同初始硝基苯质量浓度对其最终降解率影响不大;在含有不同价态铁、初始pH=6的厌氧污泥体系中,对硝基苯降解起主导作用的是厌氧污泥,Fe0在一定程度上促进了硝基苯的降解,而Fe2+,Fe3+则表现出抑制作用,尤以Fe3+最为显著;但当反应体系初始pH=9时,Fe2+和葡萄糖的存在则显著促进了硝基苯的降解.

Effects of Fe0/Fe2+/Fe3+ on Nitrobenzene Anaerobic Degradation and Influencing Factors

The influence of Fe0/Fe2+/Fe3+ on the nitrobenzene (NB) anaerobic degradation was studied and the initial NB concentration,pH and glucose concentration affecting the degradation process of NB were investigated.The primary product of NB degradation was aniline,which significantly increased its biodegradability characteristics.NB in the anaerobic system was degraded completely at pH 6,but the initial NB concentration had no significant effect on NB degradation rate.A substantial proportion of NB was degraded by the anaerobic sludge in the mixed system of Fe0 and anaerobic sludge at pH 6.An accelerative effect on NB degradation came into being when adding Fe0 into the anaerobic system,and inhibited the NB degradation when adding Fe2+/Fe3+,especially Fe3+.When pH was shifted to pH 9,the existing Fe2+ and glucose in the system significantly promoted the NB degradation.