乳化植物油强化地下水中Cr(VI)的生物地球化学还原研究.PDF

中国环境科学 2015,35(6) ：1693~1699 China Environmental Science 乳化植物油强化地下水中 Cr(VI)的生物地球化学还原研究 生 贺 1,2,于锦秋 1.2,刘登峰 1,2,董 军 1,2* (1.吉林大学环境与资源学院,吉林 长春 130021 ；2 吉林大学地下 水资源与环境教育部重点实验室,吉林 长春 130021) 摘要：设计天然细砂模拟实验,利用乳化植物油作为电子供体,研究生物地球化学作用对 Cr(VI)的还原过程和机理.结果表明,乳化油可以使 地下水呈弱酸性,反应体系 pH 值最终为 6.59;并长期维持还原环境,Eh 最终降低至-158.6mV.乳化油可显著促进土著微生物的异化铁还原作 用,将细砂介质中 Fe(III)还原成 Fe(II)并耦合去除 Cr(VI).当反应进行到 14d 时,Cr(VI)全部被去除,反应第 28d 总铬完全被去除.Fe(II)的累 积对反应体系中的氧化还原环境有重要影响.当实验结束时,Fe(II)浓度为 44.40mg/L,乳化油消耗了 48.9%.XPS 和 XRD 表征分析反应后 细砂,结果表明生成 Cr(III)最终以 Fe-Cr 无定型态沉淀存在. 关键词：乳化植物油；六价铬；生物地球化学；地下水 中图分类号：X703.5 文献标识码：A 文章编号：1000-6923(2015)06-1693-07 Biogeochemical Cr(VI) reduction in groundwater enhanced by emulsified vegetable oil. SHENG He1,2, YU Jin-qiu1,2, LIU Deng-feng1,2, DONG Jun1,2* (1.College of Environment and Resources, Jilin University, Changchun 130021, China ； 2.Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, China). China Environmental Science, 2015,35(6)：1693~1699 Abstract ：Natural fine sands was used as simulated aquifer media and emulsified vegetable oil as electron donor in the experiments to investigate the process and mechanisms of the biogeochemical reduction of hexavalent chromium. The experimental results showed that the emulsified vegetable oil caused a slightly pH drop, and the final pH reached 6.59; a reductive condition could be maintained for a long term, and the final Eh declined to -158.6mV. Emulsified vegetable oil could accelerate the dissimilatory iron reduction process of intrinsic microorganism; the ferric in fine sand would be reduced to ferrous and hexavalent chromium removal coupled. The hexavalent chromium and total chromium was removed absolutely within 14 and 28 d