重金属Cu(Ⅱ)在球黏土中的吸附特性

The adsorption characteristics of Cu(Ⅱ) on ball clay

通过批式吸附试验,考察球黏土对Cu(Ⅱ)的吸附效果,重点分析吸附时间、吸附剂用量、pH值以及初始质量浓度的影响。结果表明,Cu(Ⅱ)在球黏土上的吸附是一个先快速而后缓慢的过程,在60 min基本达到吸附平衡,且吸附量和吸附率随球黏土用量和Cu(Ⅱ)初始质量浓度的升高而提高。pH值对球黏土的吸附量有较大的影响,当pH值为6时,球黏土的吸附量可达97.93 mg/g。球黏土对Cu(Ⅱ)的吸附符合Langmiur等温吸附模型,拟合得到的最大吸附量为202.383 mg/g,准二阶动力学模型更适合描述球黏土对Cu(Ⅱ)的吸附过程,说明控制吸附速率的主要是化学吸附。与其他常见的黏土吸附剂材料相比,球黏土对Cu(Ⅱ)具有良好的吸附性能,可以作为天然矿物吸附剂来处理含Cu(Ⅱ)废水。

In order to study the adsorption characteristics of ball clay,the effect of adsorption time,ball clay dosage,pH values and initial concentration of Cu(Ⅱ)were examined by the batch experiments.The results suggested that the adsorption of Cu(Ⅱ)on ball clay was a fast and then slow process.Which almost achieved adsorption equilibrium after 60 minutes and the adsorption capacity and adsorption rate were increased with the increase of ball clay dosage and initial concentration of Cu(Ⅱ).The pH value had a great impact on the adsorption of ball clay and when the pH value was 6,the adsorption capacity was obtained over 97.93 mg/g.The adsorption of Cu(Ⅱ)on the ball clay followed the Langmiur isotherm model,and the maximum adsorption capacity obtained was 202.383 mg/g.The pseudo-second-order kinetics model was more suitable to describe the adsorption process of Cu(Ⅱ),which indicated that the adsorption rate was controlled by chemisorption.Compared with other pure clay adsorbent materials,the ball clay had a high ability to adsorb copper ions and could be used as a natural mineral adsorbent to treat industrial wastewater containing copper ions.