铅锌矿尾矿吸附水溶液中碱性品绿的研究

摘要

以铅锌矿尾矿(TLZO)作为吸附剂,研究不同条件下吸附水溶液中碱性品绿(BG)的特性,并对其吸附机理进行探讨.结果表明:pH值对BG的吸附有显著影响,最佳pH值为7.0；TLZO吸附BG是一个快速的过程,40min即达到平衡.随着初始浓度的增加,吸附量越大,达到平衡所需的时间越长；动力学数据较好地符合拟二级动力学方程.初始阶段外扩散过程对TLZO吸附BG的速率影响较大；在内扩散过程中,同一初始浓度下速率常数Kp,2＞ Kp,3,同一扩散阶段的速率随着初始浓度的升高而升高.TLZO对BG的等温吸附行为较好地符合Freundlich吸附等温模型.%The adsorption of basic green (BG) from an aqueous solution using tailings of lead-zinc ore (TLZO) under different conditions was studied, and the adsorption mechanism was investigated. The experimental results show the following: The pH value of the solution significantly affected the adsorption of BG. The optimum pH value was 7.0. The process of BG adsorption by TLZO was quick and equilibrium was attained within 40 minutes. As the initial concentration increased, the adsorption capacity increased and the time required to attain equilibrium lengthened. The kinetic parameters were evaluated and showed good correlation with the pseudo-second-order kinetic model. The external diffusion at the initial stage had a great effect on the rate of adsorption of BG by TLZO. In the intra-particle diffusion process, the rate parameter K?t2 was larger than Kp 3 at the same initial concentration, and the rate parameter at the same diffusion stage increased with the initial concentration. The isothermal adsorption of BG by TLZO conformed well to the Freundlich adsorption isotherm model.