化学改性对沸石去除水中碳、氮污染物的影响

为提高沸石对水中多种污染物的去除效果,以水溶液中低浓度氨氮、硝态氮和有机物为研究对象,重点研究了乙酸、柠檬酸、柠檬酸钠、十二烷基磺酸钠(SDS)、氯化钠、十六烷基三甲基溴化铵(HDTMA)6种不同无机\有机化学改性剂对沸石去除氨氮、硝态氮、COD的影响.研究表明,对低浓度氨氮去除效果最好的为柠檬酸钠改性沸石,最佳浓度为0.05 mol/L,去除率为98.14％;对低浓度硝态氮去除效果最好的为HDTMA改性沸石,最佳浓度为0.05 mol/L,去除率为24.81％;对低浓度COD去除效果最好的为柠檬酸改性沸石,最佳浓度为0.05 mol/L,去除率为42.57％,且改性沸石阳离子交换容量的大小与其对氨氮的去除率呈正相关.同时得出了不同改性剂对沸石去除氨氮、硝态氮、COD的影响规律,并发现柠檬酸钠改性沸石同步去除水溶液中低浓度氨氮、硝态氮和COD的效果远高于原天然沸石.

Effects of Chemical modification on Removal of Pollutants with Carbon and Nitrogen from Aqueous Solution by Zeolite

The effects of six chemical modification agents (acetic acid, citric acid, sodium citrate, SDS, sodium chlorite, HDTMA) on the removal rates of low concentration of ammonia nitrogen, nitrate nitrogen and COD by zeolite have been studied in this paper. The results showed that the zeolite modified by 0.05mol/L of sodium citrate had the largest ammonia nitrogen removal rate, which was 98.14%; the zeolite modified by 0.05mol/L of HDTMA had the largest nitrate nitrogen removal rate, which was 24.81%; and the zeolite modified by 0.05mol/L of citric acid had the largest nitrate nitrogen removal rate, which was 42.57%%. There was a positive correlation between cation exchange capacity and the removal efficiency of ammonia nitrogen. The effects law of different modification agent on the removal rates of ammonia nitrogen, nitrate nitrogen and COD by zeolite was obtained. The removal rates of ammonia nitrogen, nitrate nitrogen and COD by sodium citrate modification zeolite were higher than those of raw natural zeolite.