凹凸棒土颗粒吸附剂制备优化及对铅、铜吸附研究

Preparation Optimization of Granular Attapulgite Adsorbent and Its Adsorption Characteristics for Pb^(2+) and Cu^(2+) Removal

以凹凸棒土为基材,采取混匀、搅拌、造粒和热处理的工艺,制备颗粒状吸附剂。重点研究物料配比和焙烧温度对吸附剂去除Pb^(2+)和Cu^(2+)的影响。通过静态吸附实验研究颗粒吸附剂对Pb^(2+)和Cu^(2+)的吸附特性。结果表明随着膨润土和海藻酸钠添加剂量增大,颗粒吸附剂对Pb^(2+)和Cu^(2+)去除率增大。随着焙烧温度的提高,Pb^(2+)和Cu^(2+)的吸附去除率不断降低。凹凸棒土颗粒吸附剂对Pb^(2+)和Cu^(2+)的吸附过程遵循准一级反应动力学模型;Langmuir吸附等温式和Freundlieh吸附等温式均可较好地描述颗粒吸附剂对Pb^(2+)和Cu^(2+)的等温吸附特性。颗粒吸附剂的最佳制备条件为物料配比凹凸棒土:海藻酸钠:膨润土=100:7:8(以质量计),焙烧温度500℃。

Granular adsorbent for Pb^(2+) and Cu^(2+) removal was successfully prepared with attapulgite as the basic material by proportioning,blending,shaping and thermal treatment.The effects of the material proportioning and calcination temperature were investigated.And the adsorption characteristics of Pb^(2+) and Cu^(2+) by granular adsorbents were studied by bath reactor experiment.Results indicated that the removal ratio of Pb^(2+) and Cu^(2+) increased with the dosage increase of bentonite and sodium alginate.The removal of Pb^(2+) and Cu^(2+) decreased with the increase of calcination temperature.The kinetic processes of Pb^(2+) and Cu^(2+) could be described by the pseudo-first order kinetic model.Equilibrium isotherms were fitted well by both Freundlich model and Langmuir model.The optimal material proportioning and calcinations temperature were attapulgite:sodium alginate:bentonite = 100:7:8 wt and 500 ℃,respectively.