Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Int J Biol Macromol. 2017 Nov;104(Pt A):465-480. doi: 10.1016/j.ijbiomac.2017.06.060. Epub 2017 Jun 12.
In this work, amine riched MnFeO-cellulose was employed to remove toxic Cr (VI). To find out the optimum conditions R (3.3.1) software was used. The results of Cr (VI) adsorption onto three-step adsorbents were compared by interpreting kinetic and isotherm studies. The kinetic studies reveal that the adsorption of Cr (VI) onto cellulose and magnetic cellulose (MC) followed pseudo-first order model whereas the adsorption of Cr (VI) onto amine modified cellulose (AFMC) followed pseudo-second order kinetic model. From the obtained intraparticle diffusion model results it is evident that the adsorption is an external surface process. The adsorption isotherm parameters for Cr (VI) adsorption onto MC and AFMC showed that the correlation coefficient (R: 0.96, 0.88) of Freundlich isotherm is more than that of Langmuir isotherm (R: 0.50, 0.76); hence, it is suggested that the adsorption of Cr (VI) onto these sorbents occurs in multilayer possessing heterogeneous sorption sites whereas the adsorption onto cellulose followed Langmuir model. The maximum adsorption capacities of cellulose, MC and AFMC under optimum conditions were found to be 25, 125 and 250mg/g, respectively; thus, it is confirmed that adsorption efficiency has been improved after modification steps.
在这项工作中,采用富含胺的 MnFeO-纤维素去除有毒的 Cr(VI)。为了找到最佳条件,使用了 R(3.3.1)软件。通过解释动力学和等温线研究,比较了三步骤吸附剂对 Cr(VI)的吸附效果。动力学研究表明,Cr(VI)在纤维素和磁性纤维素(MC)上的吸附遵循准一级动力学模型,而在胺改性纤维素(AFMC)上的吸附遵循准二级动力学模型。从获得的内扩散模型结果可以明显看出,吸附是一个外部表面过程。MC 和 AFMC 对 Cr(VI)的吸附等温线参数表明,Freundlich 等温线的相关系数(R:0.96、0.88)大于 Langmuir 等温线(R:0.50、0.76);因此,建议 Cr(VI)在这些吸附剂上的吸附发生在具有异质吸附位点的多层中,而在纤维素上的吸附遵循 Langmuir 模型。在最佳条件下,纤维素、MC 和 AFMC 的最大吸附容量分别为 25、125 和 250mg/g,因此,证实了经过修饰步骤后吸附效率得到了提高。