负载型纳米铁化学反硝化法去除硝酸盐氮的研究  

Study on Nitrate Nitrogen Removal in Chemical Denitrification by Supported Nano Zero-valent Iron

作　　者：张环[1] 金朝晖[1] 韩璐[1] 王薇[1] 修宗明[1] 高思[1] 

机构地区：[1]南开大学环境科学与工程学院

出　　处：《中国给水排水》2006年第15期83-87,共5页China Water & Wastewater

基　　金：国家自然科学基金资助项目(20477019)

摘　　要：采用液相还原法制备了以石墨为载体的负载型纳米铁,并以其为还原剂进行化学反硝化,考察了此种材料还原硝酸盐氮的特性。结果表明,负载型纳米铁在中性条件下能够快速将硝酸盐氮还原而去除;铁量相同而不同铁碳比的负载型纳米铁还原硝酸盐氮的速率有所不同;体系初始pH值越低则负载型纳米铁还原硝酸盐氮的速率越快,pH值为2时可在15 m in内将浓度为80mg/L的硝酸盐氮全部去除;体系中的溶解氧会与NO3-争夺电子,在pH值较低时NO3-的还原受溶解氧的影响较大;负载型纳米铁可构成微小原电池,在化学反硝化反应中Fe起主要作用,Fe2+对反应有促进作用。Supported nano zero-valent iron was prepared by the reduction of an aqueous iron salt when graphite was used as the supporting material. The reduction of nitrate nitrogen by this material was investigated. Experimental results show that the supported nano zero-valent iron can rapidly reduce nitrate nitrogen. The reaction rates of the nitrate nitrogen reduction are different due to the materials of different ratios of iron and graphite. The low pH value condition is more favorable for nitrate nitrogen reduction. After 15 min of reaction with the initial pH of 2, nitrate nitrogen of 80 mg/L is entirely degraded. The efficiency of nitrate nitrogen removal decreases as the DO contests with nitrate nitrogen for the electron acceptor. This phenomenon is more obvious at acidic conditions. Based on the research data, the reaction pathways for nitrate nitrogen reduction by supported nano zero-valent iron have been proposed.

关 键 词：负载型纳米铁 石墨 化学反硝化 硝酸盐氮 

分 类 号：TU991.26[建筑科学—市政工程]