Porkodi K, Vasanth Kumar K
CIQ-UP, Department of Chemistry, Faculty of Science, University of Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
J Hazard Mater. 2007 May 8;143(1-2):311-27. doi: 10.1016/j.jhazmat.2006.09.029. Epub 2006 Sep 15.
Batch experiments were carried out for the sorption of eosin yellow, malachite green and crystal violet onto jute fiber carbon (JFC). The operating variables studied are the initial dye concentration, initial solution pH, adsorbent dosage and contact time. Experimental equilibrium data were fitted to Freundlich, Langmuir and Redlich-Peterson isotherm by non-linear regression method. Langmuir isotherm was found to be the optimum isotherm for eosin yellow/JFC system and Freundlich isotherm was found to be the optimum isotherm for malachite green/JFC and crystal violet/JFC system at equilibrium conditions. The sorption capacities of eosin yellow, malachite green and crystal violet onto JFC according to Langmuir isotherm were found to 31.49 mg/g, 136.58 mg/g, 27.99 mg/g, respectively. A single stage batch adsorber was designed for the adsorption of eosin yellow, malachite green and crystal violet onto JFC based on the optimum isotherm. A pseudo second order kinetic model well represented the kinetic uptake of dyes studied onto JFC. The pseudo second order kinetic model successfully simulated the kinetics of dye uptake process. The dye sorption process involves both surface and pore diffusion with predominance of surface diffusion at earlier stages. A Boyd plot confirms the external mass transfer as the rate limiting step in the dye sorption process. The influence of initial dye concentration on the dye sorption process was represented in the form of dimensionless mass transfer numbers (Sh/Sc(0.33)) and was found to be agreeing with the expression:
进行了批量实验，以研究黄曙红、孔雀石绿和结晶紫在黄麻纤维碳（JFC）上的吸附情况。研究的操作变量包括初始染料浓度、初始溶液pH值、吸附剂用量和接触时间。通过非线性回归方法将实验平衡数据拟合到Freundlich、Langmuir和Redlich-Peterson等温线。结果发现，Langmuir等温线是黄曙红/JFC体系的最佳等温线，而在平衡条件下，Freundlich等温线是孔雀石绿/JFC和结晶紫/JFC体系的最佳等温线。根据Langmuir等温线，黄曙红、孔雀石绿和结晶紫在JFC上的吸附容量分别为31.49 mg/g、136.58 mg/g、27.99 mg/g。基于最佳等温线，设计了一个单级批量吸附器，用于黄曙红、孔雀石绿和结晶紫在JFC上的吸附。拟二级动力学模型很好地描述了所研究的染料在JFC上的动力学吸附过程。拟二级动力学模型成功地模拟了染料吸附过程的动力学。染料吸附过程涉及表面扩散和孔扩散，在早期阶段以表面扩散为主。Boyd图证实了外部传质是染料吸附过程中的速率限制步骤。初始染料浓度对染料吸附过程的影响以无量纲传质数（Sh/Sc(0.33)）的形式表示，并且发现与以下表达式一致：
