Effect of Natural Zeolite and Modified Zeolite on Adsorption and Desorption of Cu~(2+)

This test has studied the influence of natural zeolite and modified zeolites on the adsorption and desorption characteristic of Cu2+.The adsorption isotherm of natural zeolite,modified zeolites to Cu2+ are conformed to the Langmuir equation,the Freundlich equation and the Temkin equation.As for natural zeolite and modified zoelites,the correlation coefficients of Freundlich equation is the highest.The adsorptive capacity order of four kinds of zeolites to the Cu2+ is NH4-zeolite K-zeolite Mg-zeolite Zeolite.The order related closely to the valences and hydrated radius of the coordinated cations.Desorption capacity and desoption rate order of zeolite and modified zeolite is zeolite Mg-zeolite K-zeolite NH4-zeolite.TheA-zeolite,K-zeolite and Mg-zeolite may not only enhance the adsorption of Cu2+,can but also reduce the desorption ratio of Cu2+.So modified zeolites has a broad application prospect in the agricultural practice,especially in soil contaminated by heavy metals.