Hameed B H, El-Khaiary M I
School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia.
J Hazard Mater. 2008 Jun 15;154(1-3):639-48. doi: 10.1016/j.jhazmat.2007.10.081. Epub 2007 Oct 30.
In this paper, broad bean peels (BBP), an agricultural waste, was evaluated for its ability to remove cationic dye (methylene blue) from aqueous solutions. Batch mode experiments were conducted at 30 degrees C. Equilibrium sorption isotherms and kinetics were investigated. The kinetic data obtained at different concentrations have been analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The experimental data fitted very well the pseudo-first-order kinetic model. Analysis of the temportal change of q indicates that at the beginning of the process the overall rate of adsorption is controlled by film-diffusion, then at later stage intraparticle-diffusion controls the rate. Diffusion coefficients and times of transition from film to pore-diffusion control were estimated by piecewise linear regression. The experimental data were analyzed by the Langmuir and Freundlich models. The sorption isotherm data fitted well to Langmuir isotherm and the monolayer adsorption capacity was found to be 192.7 mg/g and the equilibrium adsorption constant Ka is 0.07145 l/mg at 30 degrees C. The results revealed that BBP was a promising sorbent for the removal of methylene blue from aqueous solutions.
本文对农业废弃物蚕豆皮（BBP）从水溶液中去除阳离子染料（亚甲基蓝）的能力进行了评估。在30℃下进行了间歇模式实验，研究了平衡吸附等温线和动力学。使用准一级、准二级和颗粒内扩散方程对不同浓度下获得的动力学数据进行了分析。实验数据非常符合准一级动力学模型。对q的时间变化分析表明，在过程开始时，吸附的总速率受膜扩散控制，随后在后期颗粒内扩散控制速率。通过分段线性回归估计了扩散系数和从膜扩散到孔扩散控制的转变时间。用Langmuir和Freundlich模型对实验数据进行了分析。吸附等温线数据很好地拟合了Langmuir等温线，在30℃下，单层吸附容量为192.7 mg/g，平衡吸附常数Ka为0.07145 l/mg。结果表明，BBP是一种从水溶液中去除亚甲基蓝的有前景的吸附剂。
