Department of Environmental Science and Engineering, Kyung Hee University, Yongin-si, Gyeonggi-do, Republic of Korea.
Bioprocess Biosyst Eng. 2013 Feb;36(2):231-8. doi: 10.1007/s00449-012-0779-0. Epub 2012 Jul 20.
Electrochemical treatment of nitrate ions was attempted using different catalysts on the cathode in bioelectrochemical denitrification systems. The carbon cathode coated by biofilm (biocathode) could remove 91 % of nitrate ions at 1.0 V, which was almost same as the Pt-coated electrode (90 %). The exchange current density of biocathode was 0.0083 A/m(2), which was almost 22 times higher than with an abiotic plain carbon cathode. The formation of intermediate products in nitrate reduction varied depending on the cell voltage. At 0.5 V, a large portion of nitrate was converted to ammonia, but at more increased cell voltage (0.7 and 1 V) a high amount of nitrite ions was found with little ammonia formation in cathodic solution. The maximum nitrate removal rate was 0.204 mg NO(3)-N/cm(2)d by biocathode, while plain carbon paper showed only 0.176 mg NO(3)-N/cm(2)d. Electrochemical analysis of chronoamperometry showed a higher stable current generation for biocathode (3.1 mA) and Pt-coated cathode (2.8 mA) as compared to plain carbon (0.6 mA) at 0.7 V of poised voltage.
采用生物电化学反硝化系统中的阴极不同催化剂对硝酸盐离子进行电化学处理。涂覆生物膜的碳阴极（生物阴极）在 1.0 V 时可去除 91%的硝酸盐离子，几乎与 Pt 涂层电极（90%）相同。生物阴极的交换电流密度为 0.0083 A/m(2)，几乎是无生命普通碳阴极的 22 倍。硝酸盐还原过程中中间产物的形成取决于电池电压。在 0.5 V 时，大部分硝酸盐转化为氨，但在更高的电池电压（0.7 和 1 V）下，阴极溶液中发现大量的亚硝酸盐离子，氨的生成量很少。生物阴极的最大硝酸盐去除速率为 0.204 mg NO(3)-N/cm(2)d，而普通碳纸仅为 0.176 mg NO(3)-N/cm(2)d。恒电位计时安培法的电化学分析表明，与普通碳（0.6 mA）相比，生物阴极（3.1 mA）和 Pt 涂层阴极（2.8 mA）在 0.7 V 偏置电压下产生的稳定电流更高。
