沸石吸附微污染水源水中氨氮的研究

Study on Adsorption of Ammonia Nitrogen From Micro-polluted Raw Water by Zeolite

研究沸石吸附微污染水源水中氨氮的吸附效能。采用预处理的60~75目浙江缙云天然沸石和改性沸石吸附微污染水源水中的氨氮,通过等温吸附试验、吸附热力学试验、吸附动力学试验以及颗粒内扩散试验,比较了解天然沸石和改性沸石对氨氮的吸附性能。试验结果表明,天然沸石和改性沸石对氨氮的吸附过程均符合Freundlich等温方程;天然沸石和改性沸石吸附氨氮的反应均是自发进行的熵减型反应,吸附氨氮的过程是放热过程;天然沸石和改性沸石的准二级动力学方程的R^2分别为0.996 8、0.999 3,相关性高于准一级动力学方程,因此用Lagergren准二级动力学模型可以更好的描述天然沸石和改性沸石吸附氨氮的动力学过程;天然沸石和改性沸石吸附氨氮是一个多步骤控制的过程。

The adsorption efficiency of ammonia nitrogen in water source with zeolite adsorption was studied. At first, 60～75 mesh pretreated Zhejiang Jinyun natural zeolite and modified zeolite were used to adsorb ammonia nitrogen in the micro-polluted source water. And then, through the isothermal adsorption test, adsorption kinetics test, adsorption kinetics test and particle diffusion test, the adsorption effects of natural zeolite and modified zeolite for ammonia nitrogen were compared. The experimental results show that the natural zeolite and modified zeolite are more in accordance with the Freundlich isothermal equation. The ammonia nitrogen adsorption reaction of natural zeolite and modified zeolite is spontaneous entropy reduction reaction, and the adsorption process of ammonia nitrogen is exothermic process. The R～2 of quasi-second order kinetic equation of natural zeolite and modified zeolite is 0.996 8 and 0.993 3, and the correlation is higher than that of quasi-first order kinetic equation. Therefore, the Lagrone quasi-second order kinetic model can better describe Kinetics of adsorption of ammonia nitrogen on natural zeolite and modified zeolite. The ammonia nitrogen adsorption processes of natural zeolite and modified zeolite are a multi-step controlled process.