【摘要】 通过室内分析的方法研究了天然沸石及3种改性沸石对Cu2+的吸附及解吸特性。研究结果表明:沸石、改性沸石对Cu2+的等温吸附曲线符合Langmuir方程、Freundlich方程、Temkin方程,其中Freundlich方程的拟合性最好,相关系数在0.991～0.999之间。沸石及改性沸石对Cu2+吸附量大小顺序为NH4-Z>K-Z>Mg-Z>Z。该规律与改性阳离子水合半径、离子价数密切相关。沸石及改性沸石对Cu2+离子的解吸量和解吸率大小顺序为Z>Mg-Z>K-Z>NH4-Z。该规律与沸石的孔道居留效应有关。改性沸石一方面增加了Cu2+的吸附,同时又降低了Cu2+的解吸率,因此改性沸石在农业生产实践中,特别是土壤重金属污染的治理方面具有广阔的应用前景。更多还原

【Abstract】 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.更多还原