期刊
BIOCHEMICAL ENGINEERING JOURNAL
卷 31, 期 3, 页码 216-222出版社
ELSEVIER SCIENCE SA
DOI: 10.1016/j.bej.2006.08.003
关键词
adsorption; Cr(VI); treated sawdust; kinetics; isotherm and thermodynamics
The studies on adsorption of hexavalent chromium were conducted by varying various parameters such as contact time, pH, amount of adsorbent, concentration of adsorbate and temperature. The kinetics of adsorption of Cr(VI) ion followed pseudo second order. Langmuir adsorption isotherm was employed in order to evaluate the optimum adsorption capacity of the adsorbent. The adsorption capacity was found to be pH dependant. Sawdust was found to be very effective and reached equilibrium in 3 h (adsorbate concentration 30 mg l(-1)). The rate constant has been calculated at 303, 308, 313 and 318 K and the activation energy (E,) was calculated using the Arrhenius equation. Thermodynamic parameters such as standard Gibbs energy (Delta G degrees) and heat of adsorption (Delta H-r) were calculated. The Delta G degrees and Delta H-r values for Cr(VI) adsorption on the sawdust showed the process to be exothermic in nature. The percentage of adsorption increased with decrease in pH and showed maximum removal of Cr(VI) in the pH range 4.5-6.5 for an initial concentration of 5 mg l(-1). (c) 2006 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据