Adsorption of gold from cyanide leaching solution onto activated carbon originating from coconut shell-Optimization, kinetics and equilibrium studies
Adsorption of gold from cyanide leaching solution onto activated carbon originating from coconut shell-Optimization, kinetics and equilibrium studies
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DOI：
10.1016/j.jiec.2017.06.036
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发表时间：
2017-10-25
影响因子：
6.1
通讯作者：
Agarwal, Shilpi
中科院分区：
文献类型：
--
作者：
Khosravi, Rasoul;Azizi, Asghar;Agarwal, Shilpi
研究了椰壳活性炭从氰化浸出液中吸附金的行为。根据CCD设计实验，采用响应面法进行实验设计，并建立二次回归模型进行回归分析。研究了pH值、搅拌速度、吸附剂浓度和吸附时间对吸附效果的影响，确定了最佳操作条件：pH值为11，搅拌速度为40 rpm，活性炭浓度为1. 25 g/L，吸附时间为3 h。在此条件下，吸附率为87.11%。并对工业氰化浸出液进行了优化条件的确定，结果表明，金的吸附率可达89.25%左右。采用准一级和准二级吸附动力学模型对吸附行为进行了动力学研究，其中准一级吸附动力学模型的相关性最好。进一步的动力学分析表明，颗粒内扩散是反应的限速步骤。吸附剂-吸附剂在298 K的相互作用进行了评估的Langmuir，Freundlich，Temkin等温线模型，其中Freundlich模型具有最高的一致性与实验数据。(C)2017年韩国工业和工程化学学会。Elsevier B. V.出版，保留所有权利。
This study investigates the behavior of gold adsorption from cyanide leaching solution onto activated coconut shell carbon. The experimental was designed according to CCD implemented with RSM and a quadratic model was developed for regression analysis. The effects of important parameters including pH, agitation rate, adsorbent concentration and adsorption time were studied to find the best operating conditions, and the optimized value of pH, agitation rate, activated carbon concentration and adsorption time was found to be 11, 40 rpm,1.25 g/L and 3 h, respectively. Under these conditions, the adsorption rate was found to be about 87.11%. Also, the optimal conditions were established on industrial cyanide leaching solution and the results demonstrated that adsorption rate of gold could be obtained about 89.25%. Adsorption behavior was kinetically investigated using pseudo first-order and pseudo second order models among which data were mostly correlated to pseudo first-order model. The further analysis of kinetics indicated that intra-particle diffusion was the rate-limiting step. Adsorbate-adsorbent interactions at 298 k was assessed by Langmuir, Freundlich, and Temkin isotherm models from which Freundlich model had the highest consistency with the experimental data. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.