人造沸石吸附解吸NH4+特征

Characteristics of adsorption and desorption on NH4+ of artificial zeolite

为寻求具有直接吸附缓释效应的环境材料,首先通过对比三种沸石对氨氮的吸附动力学行为,研究沸石吸附解吸机理,然后应用等温吸附研究沸石等温吸附特征,再结合电镜扫描、比表面积和孔径分析,采用动力吸附和等温吸附实验,研究人造沸石吸附氨氮机理以及沸石结构对其吸附性能的影响.结果表明,沸石对NH4+的吸附动力学行为符合伪二级动力学方程,NH4+浓度为400 mg·L-1时,三种沸石吸附量相差倍数最大,AZ吸附量分别是MO和CL的2.83倍和4.07倍;Freundlich方程能很好地模拟人造沸石对氨氮的吸附过程,吸附强度值大于天然沸石.

In order to seek environmental materials with direct adsorption and slow release effect,firstly,by comparing the adsorption kinetics of three zeolites on ammonia nitrogen,the adsorption and desorption mechanism of zeolite was studied,and then isothermal adsorption was used to study isothermal adsorption characteristics of zeolite.By combining with electron microscope scanning,specific surface area and Pore size analysis and using dynamic adsorption and isothermal adsorption experiments,the mechanism of adsorption of ammonia nitrogen was studied by artificial zeolite and the effect of zeolite structure on its adsorption performance.The results indicate that the ammonia nitrogen adsorption kinetic data of zeolites followed pseudo-second order kinetics equation,the adsorption capacity reaches the biggest difference when the concentration of ammonia nitrogen was 400 mg/L,and the maximum adsorption capacity of AZ on ammonia nitrogen is 28.42 mg·g-1,which is 2.83 times MO and 4.07 times CL;adsorption isotherm conformed to the Freundlich equation,Kf value of adsorption strength parameters is greater than that of natural zeolite.Zeolite’s absorbent ability against ammonia nitrogen can be promoted by its loss interior structure,molecular size,uniform particles form and high crystal structure.The advantage of adsorption and desorption on ammonia nitrogen of artificial zeolite can provide theoretical basis for further development and utilization of artificial zeolite.