生物质炭对水溶液中Pb^(2+)的吸附性能研究

Biochar: Adsorption Property to Pb^(2+) in Aqueous Solution

针对山西省土壤Pb^(2+)污染问题,选择一种环保及可循环利用的生物质材料。以农业废弃物小麦秸秆和花生壳制备而成的生物质炭为材料,通过平衡吸附法确定影响吸附的最佳条件。结果表明,当Pb^(2+)初始浓度为200 mg/L时,生物质炭添加量8 g/L,pH 3～7,25℃条件下振荡360 min,为最适吸附条件,吸附效果最好,吸附量达24.85 mg/g,去除率达99.38%。该种生物质炭对Pb^(2+)的吸附符合二级动力学方程和Langmuir等温吸附模型,R^2分别达0.9994和0.9985。研究表明,用小麦秸秆和花生壳制备而成的生物质炭在一定条件范围内对Pb^(2+)具有良好的去除作用。

Aiming at the problems of soil Pb2+pollution in Shanxi,we conducted a research to select an environmentally friendly and recyclable biomass material.Taking the biochar prepared from agricultural waste(wheat straw and peanut shell)as the material,we determined the optimal conditions affecting the adsorption by equilibrium adsorption method.The results showed that:when the initial concentration of Pb2+was 200 mg/L,the optimum adsorption condition was the biochar adding amount of 8 g/L,the pH value of 3-7,and the shock of360 min at 25℃,and the best adsorption effect was achieved with the adsorption amount of 24.85 mg/g and the removal rate of 99.38%.The adsorption of Pb2+by this kind of biochar accords with the second-order kinetic equation and the Langmuir isotherm adsorption model,and R2 reaches 0.9994 and 0.9985,respectively.This study shows that the biochar prepared from the wheat straw and peanut shell has a good removal effect on Pb2+under certain conditions.