改性沸石去除水中氨氮的试验分析

Experimental Study on Ammonia-Nitrogen Removal in Water by Modified Zeolite

目的通过改性沸石与天然沸石除氨氮的吸附试验研究,考察在不同氨氮质量浓度条件下,改性沸石与天然沸石对氨氮的去除效果.方法分别采用HCl、NaOH、NaCl和AlCl3对天然沸石进行改性,通过静态吸附试验,对比4种改性沸石和天然沸石对氨氮的去除率和吸附量.结果NaCl改性沸石对氨氮的去除效果最佳,其去除率可达93.28%,HCl改性沸石次之,其次是NaOH改性沸石,再其次是天然沸石,而AlCl3改性沸石去除效果最差.NaCl改性沸石对氨氮的吸附规律较好的符合Langmuir吸附等温式,其投加量和搅拌时间对氨氮的去除效果有一定的影响,最佳投加量为0.5 g,最佳搅拌时间为30 min.结论NaCl改性可以有效地提高天然沸石的吸附容量,对氨氮的去除效果远远优于天然沸石.

In this paper, the removal efficiency of ammonia-nitrogen with modified zeolite and natural zeolite is studied by static adsorption experiment of ammonia-nitrogen under the different concentrations of ammonia-nitrogen. HCl, NaOH, NaCl and AlCl3 are respectively adopted to modify the natural zeolite. We compared the removal rates of ammonia- nitrogen and adsorption capacity of these four different types of modified zeolite and natural zeolite by static adsorption experimentation. The results show that the removal efficiency of NaCl modified zeolite is the best, and its removal rate can reach 93.28 %. The HCl modified zeolite is better and the NaOH modified zeolite follows it, the natural zeolite＇ s is worse, but the AlCl3 modified zeolite is the worst. The regularity of ammonia- nitrogen absorption by NaC1 modified zeolite conforms to the Langmuir isothermal adsorption model. The dosage of NaCl modified zeolite and agitation time contribute to the removal efficiency of ammonia - nitrogen, too. The optimal dosage is 0.5 g and the optimal agitation time is 30 min. Therefore, it is safe to draw the conclusion that NaCl modified zeolite can effectively improve the adsorption capacity of the natural zeolite, and its removal efficiency of ammonia- nitrogen is much better than that of the natural zeolite.