溶液中Fe^(2+)强化Fe^0还原NO_3^-的机制  

Mechanism of promotion effect of Fe^(2+) on nitrate reduction by Fe^0

作　　者：陈占[1,2] 王海波[2] 韩陆超[2] 胡学香[2] 赵丹[1] 

机构地区：[1]苏州科技大学环境科学与工程学院,苏州215011 [2]中国科学院生态环境研究中心,北京100085

出　　处：《环境工程学报》2016年第9期4940-4944,共5页Chinese Journal of Environmental Engineering

基　　金：中国科学院生态环境研究中心青年科学基金资助项目(RCEES-QN-20130022F)

摘　　要：通过不同条件下Fe0还原NO-3的研究发现,在中性条件下溶液中Fe^(2+)明显强化了Fe0对NO-3的还原,最终还原产物以NH+4-N为主,而反应过程中Fe^(2+)消耗与NO-3还原量存在明显的正相关性。在Fe^(2+)初始浓度为1~8 mmol·L-1条件下,6 g·L-1的Fe0对初始浓度为100 mg·L-1NO-3的还原符合零级反应动力学过程,结合电化学和X射线衍射分析,证明Fe^(2+)通过沉积到Fe0表面,加速了电子传递过程,促进Fe0表面活性,从而强化了Fe0对NO-3的还原。In this work, nitrate reduction by Fe＋ under different conditions was studied. The results indi- cated that dissolved Fe2＋ promoted the reduction of NO3- at a neutral pH. NH4-N was the main reduction prod- uct, and the amount of consumed Fe2＋ correlated positively with the amount of nitrate reduction. Moreover, with an initial concentration of 1 to 8 mmol · L-1 Fe2＋ , 100 mg· L-1 of nitrate （initial concentration） was reduced by 6 g · L-1 Fe0; this process conformed to zero-order reaction kinetics. Electrochemical measurements and X- ray powder diffraction （XRD） results indicated that Fe2＋ accelerated the electron transfer process by precipitat- ing on the surface of iron, which in turn promoted the surface activity of Fe0 , and accelerated nitrate reduction.

关 键 词：Fe(2+) NO-3还原 反应动力学 电子传递 

分 类 号：X703[环境科学与工程—环境工程]