凹凸棒土颗粒吸附剂制备优化及对铅、铜吸附研究

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℃。

Preparation optimization of granular attapulgite adsorbent and its adsorption characteristics for Pb2+ and Cu2+ removal

Granular adsorbent for Pb2+ and Cu2+ 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 Pb2+ and Cu2+ by granular adsorbents were studied by bath reactor experiment. Results indicated that the removal ratio of Pb2+ and Cu2+ increased with the dosage increase of bentonite and sodium alginate. The removal of Pb2+ and Cu2+ decreased with the increase of calcination temperature. The kinetic processes of Pb2+ and Cu2+ 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 oC, respectively.