酸改性凹凸棒土处理含铜废水的试验研究
Experimental study on adsorption of copper containing wastewater by modified attapulgite
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摘要: 通过酸改性凹凸棒土处理含铜废水试验,研究了酸改性凹凸棒土对含铜废水的吸附性能、吸附过程、吸附热力学、吸附动力学及影响因素。结果表明:在1 mol/L的盐酸改性条件下,凹凸棒土的吸附效率较改性前提升38.61%,酸改性能活化凹凸棒土,显著提高其吸附性能。在温度为20 ℃,铜离子初始浓度为100 mg/L,酸改性凹凸棒土投加量为6 g/L(以铜离子浓度计)的最佳反应条件下,反应25 min后,凹凸棒土对铜离子的去除率达87.57%;凹凸棒土对铜离子的吸附符合一级动力学方程(R 2为0.929)与Redlich-Peterson等温吸附方程(R 2为0.984),表明凹凸棒土的吸附过程属于物理吸附,且随着铜离子初始浓度的提高,凹凸棒土的吸附容量也随之增大。Abstract: The experiment of adsorption of copper containing wastewater by modified attapulgite was performed to study the adsorption performance, process, thermodynamics, kinetics and its influence factors of modified attapulgite on copper containing wastewater. The results showed that the adsorption efficiency of acid modified attapulgite increased by 38.61% under the condition of 1 mol/L HCl, which indicated that the acid modification could activate the pore structure in attapulgite so as to significantly improve the adsorption performance. The maximum removal rate of copper ions by attapulgite could be up to 87.57% at the optimum reaction conditions as follows: the initial copper ion concentration of 100 mg/L, at temperature of 20 ℃ and the dosage of acid-modified attapulgite of 6 g/L. The adsorption of attapulgite on the copper containing wastewater was in accordance with the first-order kinetic equation and the Redlich-Peterson isotherm equation, and the fitting correlation coefficients R 2 were 0.929 and 0.984 respectively, indicating that the adsorption process of attapulgite could be classified as physical adsorption. With the initial concentration of copper ions increasing, the modified attapulgite has a good adsorption effect on copper containing wastewater.