Wang Qian, Xu Xinhua, Zhao Fanglin, Liu Zhihao, Xu Jinan
Department of Environmental Engineering, Zhejiang University, Zheda Road 38#, Hangzhou 310027, China.
Water Sci Technol. 2010;61(11):2889-96. doi: 10.2166/wst.2010.186.
Chromium(VI) is a priority pollutant in soils and wastewaters and reduction of Cr(VI) to Cr(III) is a solution to this problem. In this study a low-cost method was proposed to adapt indigenous bacteria and use them to reduce Cr(VI) in solutions. The experiment results show that Cr(VI) could be efficiently reduced by indigenous bacteria under anaerobic and pH-unadjusted conditions. After about 24 h the concentration of Cr(VI) could be reduced from 21.74 mg/L to below 0.5 mg/L. The observed Cr(VI) reduction rates were affected by temperature and pH. Cr(VI) in aqueous solutions could be reduced to Cr(III) completely and partly be incepted by the organisms. Cr(VI) reduction was enzyme-mediated. It was not an energy-conserving process but a detoxification reaction. This method could be used in an anaerobic reactor to treat low-concentration wastewater or industrial water as the last step.
六价铬是土壤和废水中的优先污染物，将六价铬还原为三价铬是解决该问题的一种方法。本研究提出了一种低成本方法，用于驯化本土细菌并利用它们来还原溶液中的六价铬。实验结果表明，在厌氧和未调节pH值的条件下，本土细菌能够有效地还原六价铬。约24小时后，六价铬的浓度可从21.74毫克/升降至0.5毫克/升以下。观察到的六价铬还原率受温度和pH值的影响。水溶液中的六价铬可被完全还原为三价铬，部分被生物体摄取。六价铬的还原是由酶介导的。这不是一个能量守恒过程，而是一种解毒反应。该方法可用于厌氧反应器中，作为处理低浓度废水或工业用水的最后一步。
