中文摘要：

采用循环伏安法探明了“Achromobacter sp. CH-1-Cr（Ⅵ）-水”体系的电化学行为.结果表明：循环伏安曲线上-0.62V（相对于SCE）的电流峰对应的反应为Cr（VI）还原成Cr（Ⅲ）的反应,在电势为-0.82V时Cr（Ⅲ）开始还原为零价铬.体系中的电极反应为不可逆过程,阳极扫描时Cr（Ⅲ）不会被重新氧化为Cr（Ⅵ）.细菌的存在使Cr（Ⅵ）的还原更容易进行,其还原峰电势正移约0.2V,细菌对体系中的电化学反应起了催化作用.随细菌量的增加,氢气的析出、六价铬还原为三价铬及三价铬进一步还原为零价铬的电势均发生了正移,过高的细菌量主要影响三价铬还原沉积为金属铬的过程.铬浓度对细菌还原Cr（Ⅵ）溶液的循环伏安曲线的影响不大.初始pH值为10是细菌还原Cr（Ⅵ）的最佳pH值.

英文摘要：

The electrochemical behavior of an Achromobacter sp. CH-1 -Cr（ Ⅵ ） -H2O＇ system was investigated by cyclic vohammctry. Results indicated that the peak current at -0.62 V vs. SCE in the cyclic voltammetric curve represented the reduction reaction of Cr（Ⅵ） to Cr（ Ⅲ ）, and the reduction of Cr（ Ⅲ） to Cr occurred at - 0.82 V. The electrode reaction of the system was irreversible, so Cr（ Ⅲ ） could not be oxidized to Cr（Ⅵ） under positive scanning. The presence of the bacterium Achromobacter sp. CH-1 as catalyst promoted the reduction of Cr（Ⅵ） by shifting the potential of the reduction peak by 0.2 V. The reduction potentials of hydrogen evolution, reduction of Cr（ Ⅵ ） to Cr（ Ⅲ ）, and reduction of Cr（ Ⅲ ） to Cr all shifted positively with the addition of Achromobacter sp. CH-1. High bacterial biomass mainly affected the reduction process and precipitation of Cr（ Ⅲ）. However, the Cr（ Ⅵ ） concentration had a minor influence on the electrochemical behavior of the ＂Achromobacter sp. CH-1-Cr（ Ⅵ ）-H2O＇ system. An initial pH value of 10 was optimal for Cr（Ⅵ ） reduction.