沸石吸附水体中氨氮的热力学和动力学过程研究

随着近年来各大自然水体富营养化程度的加重,废水中氨氮的处理显得尤为重要。我国浙江缙云有丰富的沸石矿藏,研究其对于沸石的吸附过程有着明显的应用价值。实验结果显示:在288～318 K范围内的温度对沸石吸附氨氮过程影响较小,在氨氮初始浓度为30 mg/L的条件下,小粒径沸石对氨氮的48 h吸附容量为1.13±0.06 mg/g,去除率为91%。大粒径沸石对氨氮的48 h吸附容量为1.10±0.06 mg/g,去除率为87%。沸石对氨氮的吸附过程遵循二级吸附动力学方程,Freundlich和Langmuir等温吸附方程均适用于描述沸石吸附氨氮的热力学过程。本研究表明天然沸石是一种合适的吸附剂,可用于废水或者天然水体中氨氮的去除。

Study on thermodynamic and kinetic of ammonia inwater body adsorbed by zeolite

The treatment of ammonia in wastewater has attracted more and more attention due to the aggravation of eutrophication of natural water body recently. Jinyun of Zhejiang Province is rich in zeolite minerals, and thus the research on adsorption of zeolite has obvious practical value. The experimental results showed that temperature had little effect on ammonia adsorption within the range of 288-318K.The removal rate of ammonia is 91% within 48h while the initial concentration of ammonia is 30mg/L and the adsorption capacity is 1.13±0.06mg/g for little particle size of zeolite. While for big zeolite, 87% ammonia is removed within 48h and the adsorption capacity is 1.10±0.06mg/g. The adsorption process was found to follow the second order kinetic model. The adsorption thermodynamic could be described by both Freundlich and Langmuir.The result indicated that zeolite is a suitable absorbent and can be used in the removal of ammonia in wastewater or natural water body.