Fe阴极催化还原协同氢自养微生物反硝化深度脱氮过程和机理研究

Bio-electrochemical reactor mainly use hydrogen gas as electron donor to promote hydrogen autotrophic bacteria denitrification to remove nitrate. However, the nitrate reduction as well as hydrogen gas could both occur on the cathode with electrocatalytic nitrate reduction activity. In order to explore the synergistic relationship between electrocatalytic reduction of nitrate and catalyst of hydrogen gas for hydrogen autotrophic bacteria denitrification, this project proposed the process of advanced treatment and mechanism of electrocatalytic nitrate reduction by Fe cathode coordinated with hydrogen autotrophic denitrification. A new bio-electrochemical reactor will be constructed by using electrocatalytic active electrodes (Fe as cathode, IrO2-Pt as anode). Ascertain the nitrate removal potential of catalytic reduction of nitrate coordinated with hydrogen dependent denitrification; analysis the nitrate removal contribution of hydrogen autotrophic bacteria and electrocatalytic nitrate reduction; the electrochemical behavior of nitrate and H on cathode surface will be explored to clarify the mechanism of electrocatalysis and hydrogen evolution reaction. The effect of produced nitrite in electrocatalysis on key denitrification enzyme abundance of hydrogen autotrophic bacteria will be investigated, the effect of key enzymes on the electrocatalytic nitrate reduction pathway will also be analyzed to ascertain the synergistic relationship between electrocatalytic nitrate reduction and denitrification of hydrogen autotrophic bacteria. Afterall, the performance of this method for treating low C/N ratio nitrate wastewater will be tested.

电化学/生物自养反硝化脱氮通过利用电解水产氢作为电子供体促进氢自养微生物反硝化脱氮，然而具有硝态氮催化还原活性的电极既能发生析氢反应也能发生硝态氮还原反应。为探明电催化还原硝态氮-阴极产氢-氢自养微生物反硝化脱氮间的协同作用关系这一科学问题，本项目提出了Fe阴极催化还原协同氢自养微生物反硝化深度脱氮过程和机理研究，利用具有电催化活性的电极（Fe为阴极/IrO2-Pt为阳极）构建生物电化学反应器，探明电催化还原硝态氮协同氢自养微生物反硝化深度脱氮效率；分析氢自养微生物、电催化还原硝态氮的脱氮贡献度；探究阴极表面硝态氮和H的电化学行为，明析电催化还原硝态氮和析氢反应的协同作用机制；探明电催化中间产物亚硝酸盐对氢自养微生物反硝化脱氮关键酶活性的影响，分析反硝化脱氮关键酶对电催化还原硝态氮路径的影响，解析电催化还原硝态氮与氢自养微生物反硝化脱氮的协同作用关系。并验证该方法处理实际硝态氮废水的性能。

电化学/生物自养反硝化脱氮通过利用电解水产氢作为电子供体促进氢自养微生物反硝化脱氮，然而具有硝态氮催化还原活性的电极既能发生析氢反应也能发生硝态氮还原反应。为探明电催化还原硝态氮-阴极产氢-氢自养微生物反硝化脱氮间的协同作用关系这一科学问题，重点研究了Fe阴极催化还原协同氢自养微生物反硝化深度脱氮过程和机理研究，首先利用具有电催化活性的电极（Fe为阴极/IrO2-Pt为阳极）构建生物电化学反应器，分析电催化还原硝态氮协同氢自养微生物反硝化深度脱氮效率；使用电沉积法构建了电沉积法制备了不系列Cux-Pdy/CNTs/Ti复合电极，研究了不同Cu-Pd比例电极在三电极体系中的NO3--N转化率。构建水平潜流式Cu-Pd复合电极生物膜反应器，探究了复合电极阴极表面硝态氮和H的电化学行为，验证该方法处理实际硝态氮废水的性能。