为了探索污水处理中氨氮的优良吸附剂，对环境矿物沸石、膨润土和粉煤灰分别进行了酸、碱、盐、热改性，并对氨氮的吸附效果进行了对比试验研究。结果表明：5%钠改性沸石对氨氮吸附效果最好；影响5%钠改性沸石吸附氨氮的主次顺序为：投加量＞吸附时间＞pH值＞转速；当氨氮含量为30 mg/L时，5%钠改性沸石在投加量为20 g/L、吸附时间120 min、pH值为8、转速150 r/min的条件下，对氨氮去除效果最好可达88.34%；钠改性沸石对氨氮的吸附机理为：Na+置换了沸石中半径较大的阳离子，使沸石孔道的有效空间变大，空间位阻变小，内扩散速度加快，比表面积加大，吸附能力增强。离子交换后的钠改性沸石电负性增强，且Na+易被NH4+交换，因而NH4+可被钠改性沸石有效去除；5%钠改性沸石对氨氮的吸附符合Freundlich模型，是吸附氨氮的优良吸附剂。%In order to explore the superior adsorbent on ammonium-nitrogen, the comparative study respectively examined the bentonite, zeolite and lfy ash modiifed by hydrochloric acid, sodium hydroxide, sodium chloride, thermal to ammonium-nitrogen removal efifciency. The results show that the 5%sodium modiifed zeolite is an ideal adsorbent. Its order of affecting factors to ammonium-nitrogen is dosage>adsorption time>pH values>speed. The removal rate of ammonium-nitrogen can be as high as 88.34%when the dosage of initial ammonium-nitrogen is 30 mg/L and modiifed zeolite is 20 g/L, the adsorption time is 120 min, the pH value is 8, and the stirring intensity is 150 r/min. The adsorption mechanism of the sodium chloride modiifed adsorbent is as follow:the Na+takes place of other cations with larger radius in zeolite, and expands their available space and superifcial area. Steric hindrance of the zeolite decreases while diffusion speed increases. Consequently, the adsorption capacity and superifcial area are well improved. With the increase in electronegativity of the zeolite modiifed by sodium chloride after ion exchange and Na+being easy in exchange for NH4+, the removal of NH4+becomes more effective. The modiifed zeolite of adsorption to ammonium-nitrogen is really a superior adsorbent which is accorded with Freundlich model.
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