含铬废革屑对水体中染料的吸附

Adsorption of dyes from aqueous solution by chromium-containing leather waste

研究了含铬废革屑对水体中染料的吸附特性。结果表明 :含铬废革屑对酸性染料和直接染料有较大的吸附量 ,但对碱性染料的吸附量却较低。在酸性嫩黄G的最适吸附pH值为 3 .0的条件下 ,酸性嫩黄G的平衡浓度为 82 9mg/L ,其平衡吸附量达到 2 3 4mg/g ;在直接红棕RN的最适吸附 pH值为 9.0的条件下 ,直接红棕RN的平衡浓度为 1 1 5 7mg/L时 ,其平衡吸附量达到 1 5 2mg/g。含铬废革屑对酸性嫩黄G的吸附平衡符合Langmuir方程 ,而对直接红棕RN的吸附平衡符合Freundlich方程。吸附动力学研究表明 :含铬废革屑对以上 2种染料的吸附 ,符合拟二级速度方程。

The adsorption behaviors of chromium-containing leather waste to dyes in aqueous solution were investigated. The results indicated that acid dyes and direct dyes could be significantly adsorbed by this adsorbent. The biggest adsorption amount of acid flavine G presented at pH 3.0,where its equilibrium adsorption amount was 234 mg/g when equilibrium concentration of the dye was 829mg/L. For direct red brown RN,its biggest adsorption amount emerged at pH 9.0,where its equilibrium adsorption amount was 152 mg/g when equilibrium concentration of the dye was 1 157mg/L. The adsorption isotherms of acid flavine G could be well described by the Freundlich equation,while the Langmuir equation gave perfect fitting to the adsorption isotherm of direct red brown RN. In addition,the adsorption kinetics data of both the dyes could be well fitted by pseudo-second-order rate model.