粉煤灰制备沸石分子筛及其吸附脱除氨氮性能  

Preparation of Zeolite Molecular Sieve with Fly-ash and Its Application in Adsorbing and Removing Ammonia Nitrogen

作　　者：刘欣蕾 龚禄稍 邵艳祥 郑易帆 杨雨萌 朱本峰 卫国英[1] LIU Xinei;GONG Lushao;SHAO Yanxiang;ZHENG Yifan;YANG Yumeng;ZHU Benfeng;WEI Guoying(School of Materials and Chemistry,China Jiliang University,Hangzhou 310018,China)

机构地区：[1]中国计量大学材料与化学学院,浙江杭州310018

出　　处：《环境科学与技术》2024年第4期87-96,共10页Environmental Science & Technology

基　　金：国家自然科学基金(52001300,52171083)。

摘　　要：当前大量含氮废水的排入不仅使湖泊水体富营养化加剧,更对各类生物的生存和健康造成了很大威胁。由于沸石分子筛具有良好的吸附选择性和离子交换性,可以用来吸附脱除水中的氨氮,因此成为当前研究的热点。文章以粉煤灰为主要原料,采用碱熔融-水热法制备Na-X型沸石分子筛,通过正交试验得到沸石分子筛的最佳制备工艺条件,探索了氨氮溶液初始浓度、pH值、吸附时间、吸附温度以及阳离子对沸石分子筛吸附氨氮性能的影响。结果表明:Na-X型分子筛的最佳饱和氨氮吸附率为74.89%;Na-X型沸石分子筛吸附过程符合准二级动力学模型,吸附等温线符合Freundlich模型;其氨氮吸附量与初始浓度和吸附时间呈正相关,与温度呈负相关;强酸或强碱环境会使分子筛吸附性能下降。Na-X型分子筛氨氮吸附率较高、可多次循环使用,在废水治理方面有着广泛的应用前景。Presently,the emission of a large amount of nitrogen-containing wastewater into lakes not only aggravates lake eutrophication,but also poses severe threats to the health and survival of various species of organism.This article refers to a kind of zeolite molecular sieves that can be used to adsorb and remove ammonia nitrogen(NH3-N)from water due to the good adsorption selectivity and ion exchange.A laboratory experiment was performed with the fly-ash sampled collected from a thermo-power plant as main raw material to prepare Na-X zeolite by alkali melting-hydrothermal method,and the orthogonal experiment was conducted to determine the optimal preparation process condition.The experiment of NH3-N adsorption was thereby conducted probing into the effect of the initial NH3-N concentration,pH,adsorption time,adsorption temperature and cations on the adsorption of NH3-N by the zeolite.It was showed that the best saturated NH3-N adsorption rate of Na-X zeolite reached 74.89%,and the process of NH3-N adsorption onto Na-X zeolite fit the quasi-second-order kinetic model,and the adsorption isotherm conformed to the Freundlich model,NH3-N adsorption capacity being positively correlated with the initial NH3-N concentration and adsorption time,and negatively correlated with temperature.To sum up,the Na-X typed molecular sieve features rather high NH3-N adsorption rate,and could be recycled a number of times,so it has wide appli-cations in wastewater treatment.

关 键 词：粉煤灰 沸石分子筛 碱熔融水热法 氨氮吸附 

分 类 号：X705[环境科学与工程—环境工程]