基于建筑废弃物的轻石制备及其对Pb^(2+)的吸附机理

Preparation of Pumice Based on Construction Wastes and the Mechanism of Pb^(2+) Adsorption

文中以建筑废弃物中的废弃玻璃、水泥块为原材料制备新型吸附材料轻石,探究轻石制备的最佳制备条件和吸附机理,通过扫描电镜(SEM)、比表面积测试法(BET)、傅立叶变换红外光谱仪(FTIR)等测试分析方法对其进行物理表征,批量试验研究吸附剂投加量、Pb重金属溶液初始浓度、pH、温度等因素对轻石吸附Pb^(2+)的影响,并结合吸附动力学和吸附等温线分析其吸附机理。结果表明:当玻璃∶水泥块∶硼酸∶CaCO_(3)投加比为10∶12∶3∶2.5、烧制温度为1000℃时是轻石的最佳制备条件;25℃时轻石的最大吸附量为34μg/g,基本符合二级动力学方程和Langmuir等温吸附模型;利用轻石处理径流废水,Pb^(2+)的去除率可达90%,轻石有望成为处理雨水径流的理想吸附材料。

A new type of adsorption material pumice was made based on waste glass and cement blocks in construction waste as raw materials in this paper.Optimal preparation conditions and adsorption mechanism of pumice was explored.Scanning Electron Microscope(SEM),Brunner Emmet Teller(BET)and Fourier Transform Infrared Spectrometer(FTIR)and other analysis methods were used to characterize physics composites.Batch adsorption experiments were conducted to investigate the effect of dosage,initial concentration of Pb heavy metal solution,pH value,temperature on adsorption performance.Adsorption mechanism were analyzed from adsorption kinetics and isotherms.Results showed that under the conditions of glass powder/cement block/boric/CaCO_(3) ratio of 10∶12∶3∶2.5 and temperature of 1000℃was the best preparation conditions.Maximum adsorption capacity of pumice at 25℃was 34μg/g,which followed pseudo-second-order kinetics equation and Langmuir isotherm adsorption model.Material was used to treat runoff wastewater,and the removal of Pb^(2+) could reach 90%.Pumice is expected to be an ideal adsorption material for rainwater runoff treatment.