Onal Yunus
Department of Chemical Engineering, Faculty of Engineering, Inonu University, 44280 Malatya, Turkey.
J Hazard Mater. 2006 Oct 11;137(3):1719-28. doi: 10.1016/j.jhazmat.2006.05.036. Epub 2006 May 17.
Adsorbent (WA11Zn5) has been prepared from waste apricot by chemical activation with ZnCl(2). Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by N(2) adsorption and DFT plus software. Adsorption of three dyes, namely, Methylene Blue (MB), Malachite Green (MG), Crystal Violet (CV), onto activated carbon in aqueous solution was studied in a batch system with respect to contact time, temperature. The kinetics of adsorption of MB, MG and CV have been discussed using six kinetic models, i.e., the pseudo-first-order model, the pseudo-second-order model, the Elovich equation, the intraparticle diffusion model, the Bangham equation, the modified Freundlich equation. Kinetic parameters and correlation coefficients were determined. It was shown that the second-order kinetic equation could describe the adsorption kinetics for three dyes. The dyes uptake process was found to be controlled by external mass transfer at earlier stages (before 5 min) and by intraparticle diffusion at later stages (after 5 min). Thermodynamic parameters, such as DeltaG, DeltaH and DeltaS, have been calculated by using the thermodynamic equilibrium coefficient obtained at different temperatures and concentrations. The thermodynamics of dyes-WA11Zn5 system indicates endothermic process.
吸附剂（WA11Zn5）由废杏通过氯化锌化学活化制备而成。通过氮气吸附和DFT加软件对活性炭的孔隙特性进行了表征，如BET表面积、孔体积、孔径分布和孔径。在间歇系统中研究了三种染料，即亚甲基蓝（MB）、孔雀石绿（MG）、结晶紫（CV）在水溶液中对活性炭的吸附，考察了接触时间、温度等因素。使用六种动力学模型，即拟一级模型、拟二级模型、埃洛维奇方程、颗粒内扩散模型、班汉姆方程、修正弗伦德利希方程，讨论了MB、MG和CV的吸附动力学。确定了动力学参数和相关系数。结果表明，二级动力学方程可以描述三种染料的吸附动力学。发现染料的吸附过程在早期阶段（5分钟之前）受外部传质控制，在后期阶段（5分钟之后）受颗粒内扩散控制。利用在不同温度和浓度下获得的热力学平衡系数计算了热力学参数，如ΔG、ΔH和ΔS。染料-WA11Zn5系统的热力学表明该过程为吸热过程。
