固定化氧化还原介体加速亚硝酸盐生物反硝化作用

Biological catalyzing denitrification of nitrite by immobilized redox mediator

考察了利用循环伏安法所制备的固定化氧化还原介体(AQS/PPy/ACF)加速亚硝酸盐生物反硝化的特性,及其降解过程中pH和氧化还原电位(ORP)的变化特征。结果表明,AQS/PPy/ACF可显著地加速亚硝酸盐的生物降解;在不考虑各因子间交互作用的条件下,AQS/PPy/ACF加速亚硝酸盐降解的最佳条件为温度35℃,pH=8和碳氮比为6;AQS/PPy/ACF加速亚硝酸盐生物反硝化过程中pH的变化趋势与传统的亚硝酸盐生物反硝化过程中pH的变化趋势相似;AQS/PPy/ACF的加入可使亚硝酸盐生物反硝化过程中的ORP降低约45 mV;AQS/PPy/ACF具有较好的催化稳定性。本研究可为亚硝酸盐的生物降解提供新的技术途径,并为该技术的实际应用提供理论基础。

The immobilized redox mediator AQS/PPy/ACF prepared by cyclic voltammetry technique was studied for catalyzing denitrification of nitrite. The degradation characteristics and the change of pH and oxidation reduction potential （ORP） during the process were explored. The results suggested that the denitrification efficiency of nitrite increased prominently with AQS/PPy/ACF compared to the control;the optimal temperature,the appropriate pH and the rate of carbon and nitrogen were 35 ℃ ,8.0 and 6, respectively;the pH change with AQS/ PPy/ACF during the nitrite removal process was similar to the conventional nitrite removal process;the ORP val- ues was lower around 45 mV by AQS/PPy/ACF than the controls during the denitrification process;AQS/PPy/ ACF exhibited good stability in repeated tests. This study put forward a novel technique for the nitrite biodegrada- tion and provided a foundation for practical application.