棉秆对生物沥滤后酸化废水中铜离子的吸附动力学研究  

Removal of copper ion from the acid sewage left-over by bioleaching adsorption onto cotton stalk

作　　者：郭雪白[1] 吕晖[1] 曲来超[1] 王洁[1] 

机构地区：[1]河南理工大学万方科技学院,郑州451400

出　　处：《安全与环境学报》2014年第6期174-177,共4页Journal of Safety and Environment

摘　　要：为揭示生物质废弃物棉秆对生物沥滤后酸化废水中铜离子的吸附动力学特性,研究了棉秆作为吸附剂在不同温度下对酸化废水中铜离子的吸附动力学过程,以及棉秆对不同铜离子质量浓度酸化废水的吸附平衡效果。结果表明,伪一级动力学方程可以较好地描述棉秆对铜离子的吸附动力学特征,且在(30±1)℃条件下吻合度最好,表明铜离子质量浓度是棉秆吸附过程的主要影响因素。同时,在标准溶液、酸化废水和稀释废水3种情况下,Freundich方程能更好地解释棉秆对铜离子的吸附平衡,且3种情况下1/n相差不大,表明铜离子吸附过程受其他离子的影响不大。研究表明,棉秆的吸附能力可以满足酸化废水中铜离子去除的要求,且能在较短时间内吸附较高浓度的铜离子。This paper aims to report the investigation findings of the adsorption kinetic characteristics of copper ion in the acid sewage of bioleaching by the cotton stalk as a type of biomass waste. For this purpose, we have done the adsorption kinetics and adsorption equilibrium experiments to examine the adsorption efficiency, in which the first-order pseudo kinetics equation is used to depict the adsorption kinetic mechanism, whereas Langmuir model and Freundlich equation are used to describe the process of the adsorption equilibrium. As a result, it would be possible to describe the adsorption of copper ion from the acid sewage onto the cotton stalk better by that equation, And, the temperature of （30 ± 1） ℃ is fit best for describing the adsorption process. Thus, it has been found that the concentration of copper ions is the main factor for the adsorption by the cotton stalk. What is more, the Freundlich isotherm model has proved to be the best model for describing the adsorption equilibrium of copper ions by the cotton stalk under the following conditions： the standard solution, the acid sewage, and the dilute sewage. We have also found that the increase of the value 1/n, that is, the level of difficulty for cooper ions adsorption, has little relation to the increase of the concentration of copper ions. It implies that the other heavy metal ions have little impact on the process of the copper ions＇ adsorption. The results have thus shown that the cotton stalk could adsorb higher concentration of copper ion in less time and meet the needs of copper ion removal in the acid sewage.

关 键 词：环境工程学 酸化废水 棉秆 铜离子 吸附动力学 吸附平衡 

分 类 号：X703[环境科学与工程—环境工程]