钙法原位制备高铁酸盐降解水中草甘膦的研究  

In Situ Preparation of Ferrate by Calcium Method for Glyphosate Degradation in Water

作　　者：张娇[1] 李依 杨小春 昌晶[1] ZHANG Jiao;LI Yi;YANG Xiao-chun;CHANG Jing(School of Resources and Environment,Qingdao Agricultural University,Qingdao 266109,China)

机构地区：[1]青岛农业大学资源与环境学院,山东青岛266109

出　　处：《中国给水排水》2022年第19期76-81,共6页China Water & Wastewater

基　　金：国家自然科学基金资助项目(41301552);青岛农业大学博士启动基金资助项目(6631110307、6631121002)。

摘　　要：采用钙法原位制备高铁酸盐降解水中草甘膦,研究了pH、反应时间、高铁酸盐投加量以及进水草甘膦浓度对降解效果的影响,并对降解动力学及降解路径进行探究,对降解产物的生物毒性进行评价。试验结果表明:高铁酸盐对草甘膦的降解分为两个阶段,均符合一级反应动力学,在前10 min降解速率很快,10~90 min降解速率比较缓慢,90 min后反应基本稳定。当高铁酸盐与草甘膦投加比为1∶30(mL∶mg)、反应pH为5时,草甘膦的去除效果最好,去除率超过95%,TP去除率达77%以上,TN去除率达到40%,处理后水中主要的含氮化合物为氨氮,最大浓度为12.65 mg/L。高铁酸盐降解草甘膦过程中主要中间产物有肌氨酸、甘氨酸、磷酸、氨甲基膦酸(AMPA)、羟基乙酸和甲基膦酸,降解过程可能存在3个路径,多数降解中间产物生物毒性高于母体。Calcium method was employed to prepare ferrate in situ for degradation of glyphosate in water. The effects of pH, reaction time, ferrate dosage and influent glyphosate concentration on degradation efficiency were investigated. In addition, the degradation kinetics and degradation pathway were explored, and biotoxicity of the degradation products was evaluated. The degradation of glyphosate by ferrate consisted of two stages, and both were in accordance with the first-order reaction kinetics. The degradation rate was fast in the first 10 min, and was relatively slow in 10-90 min, and the reaction tended to be stable after 90 min. When the ratio of ferrate to glyphosate was 1∶30(mL∶mg) and the reaction pH was 5, the best removal performance of glyphosate with a removal rate of more than 95% was obtained, the removal rate of TP was more than 77%, and the removal rate of TN reached 40%. The main nitrogen compound in effluent was ammonia nitrogen, and its maximum concentration was 12.65 mg/L. The main intermediates generated in the degradation were sarsarine, glycine, phosphoric acid, AMPA, glycolic acid and methylphosphonic acid. The degradation process might include three pathways, and the biotoxicity of most intermediates was higher than that of glyphosate.

关 键 词：高铁酸盐 草甘膦 降解路径 生物毒性 

分 类 号：TU992[建筑科学—市政工程]