Adsorption of Cd(II) ions from aqueous solutions using activated carbon prepared from olive stone by ZnCl2 activation
Adsorption of Cd(II) ions from aqueous solutions using activated carbon prepared from olive stone by ZnCl2 activation
复制标题
DOI：
10.1016/j.biortech.2007.01.015
复制
发表时间：
2008-02-01
影响因子：
11.4
通讯作者：
Celik, Ali
中科院分区：
文献类型：
--
作者：
Kula, Ibrahim;Ugurlu, Mehmet;Celik, Ali
本研究旨在通过吸附去除水溶液中的Cd(II)离子。采用以农业固体副产物橄榄核为原料制备的活性碳作为吸附剂。考察了不同活化剂(氯化锌)用量和不同吸附剂粒径对吸附剂比表面积的影响。在不同的吸附剂用量、温度、平衡时间和pH条件下进行了吸附实验。实验结果表明，吸附平衡时间为60min，最适pH为6，吸附用量为1.0g/50ml。动力学数据支持准二阶模型和粒内模型，但对准一阶模型的拟合很差。得到了三种不同温度下的吸附等温线。吸附数据符合Langmuir和Freundlich等温式。此外，还计算了吸附过程的热力学参数、标准自由能(Delta G(0))、标准焓(Delta H-0)、标准熵(Delta S-0)。为了揭示所制得的活性碳的吸附特性，进行了比表面积测定。用扫描电子显微镜-能谱仪进行了结构分析。以橄榄核为原料制得的比表面积为790.25 m(2)g(-1)的活性碳中，以含20%氯化锌溶液的活性碳为最佳。结果表明，橄榄核制备的活性碳是一种可替代的低成本脱除Cd(II)的吸附剂。(C)2007爱思唯尔有限公司。保留所有权利。
This study is aimed to remove Cd(II) ions from aqueous solutions by adsorption. As adsorbent, activated carbon prepared from olive stone, an agricultural solid by-product was used. Different activating agent (ZnCl2) amounts and adsorbent particle size were studied to optimize adsorbent surface area. The adsorption experiments were conducted at different parameters such as, adsorbent dose, temperature, equilibrium time and pH. According to the experiments results, the equilibrium time, optimum pH, adsorbent dosage were found 60 min, pH > 6 and 1.0 g/50 ml respectively. The kinetic data supports pseudo-second order model and intra-particle model but shows very poor fit for pseudo-first order model. Adsorption isotherms were obtained from three different temperatures. These adsorption data were fitted with the Langmuir and Freundlich isotherms. In addition, the thermodynamic parameters, standard free energy (Delta G(0)), standard enthalpy (Delta H-0), standard entropy (Delta S-0) of the adsorption process were calculated. To reveal the adsorptive characteristics of the produced active carbon, BET surface area measurements were made. Structural analysis was performed using SEM-EDS. The resulting activated carbons with 20% ZnCl2 solution was the best sample of the produced activated carbons from olive stone with the specific surface area of 790.25 m(2) g(-1). The results show that the produced activated carbon from olive stone is an alternative low-cost adsorbent for removing Cd(II). (c) 2007 Elsevier Ltd. All rights reserved.