为降低水体中的硝态氮对环境的危害,提高污水处理厂出水水质,将催化剂运用到零价铁还原硝态氮反应中,分别对含TiO_2及Pd的催化剂进行了探索性实验。该实验以配置的KNO_3溶液为实验水样,在比较研究添加H~+、TiO_2/Al_2O_3催化剂、Pd/Al_2O_3催化剂去除效果的基础上,深入研究了负载量、载体类型、pH、溶解氧、共存离子等因素对去除效果的影响。结果表明,催化剂TiO_2/Al_2O_3对零价铁还原硝态氮的去除率有促进作用,水样pH=3.1时去除率为72%,产物主要为氨氮,应用性较差;而催化剂Pd/Al_2O_3在pH=3.1时去除率虽为43%,但产物以N_2为主。在负载量为5%的情况下,N_2转化率为76%,这对去除总氮有重要意义,并从电子转移角度探讨了该反应的反应机理,提出了活性氢(H*)为核心的机理模型。 In order to reduce the harm of nitrate nitrogen to the environment and improve the effluent quality of wastewater treatment plant, the catalyst was applied to the reduction of nitrate nitrogen in zero valent iron, and the catalytic experiments on catalysts containing TiO_2 and Pd were carried out respectively. In this experiment, the KNO3 solution was used as the experimental water sample. Based on the comparative study on the removal efficiency of H ~ +, TiO_2 / Al_2O_3 and Pd / Al_2O_3 catalysts, the effect of loading, carrier type, pH, dissolved oxygen and coexistence Ions and other factors on the removal effect. The results showed that the catalyst TiO_2 / Al_2O_3 could promote the removal rate of nitrate nitrogen by zero-valent iron reduction. The removal rate of water sample was 72% at pH = 3.1 and the product was mainly ammonia nitrogen with poor applicability. The catalyst Pd / Al_2O_3 Although the removal rate was 43% at pH = 3.1, the product was dominated by N_2. Under the loading of 5%, the conversion of N_2 is 76%, which is of great significance for the removal of total nitrogen. The reaction mechanism of the reaction is discussed from the perspective of electron transfer, and the active hydrogen (H *) is proposed as the core Mechanism model.