Experimental Investigation on Adsorptive Removal of Phenolic Compounds from Aqueous Solution by Cr-Bentonite
The ability of Cr-bentonite prepared using synthetic wastewater containing chromium was investigated for adsorptive removal of 4-aminophenol and 4-chlorophenol from aqueous solution in a batch system at 25 °C. The physic-chemical parameters including pH value of solution and contact time were studied. The experimental data were analyzed by the Langmuir, Freundlich and Temkin models of sorption. The equilibrium sorption data for 4-aminophenol and 4-chlorophenol were well fitted to Langmuir adsorption isotherm and the monolayer sorption capacity was found to be 26.53 and 23.81 mg/g at 25 °C, respectively. The sorption energy calculated from Dubinin-Redushkevich (D-R) isotherm are 8.31 and 8.20 kJ/mol for the uptake of 4-aminophenol and 4-chlorophenol respectively which indicates that both the sorption processes are chemical in nature. The kinetic data were analyzed using pseudo-first order, pseudo-second order kinetic equation and intraparticle diffusion model. The experimental data fit very well the pseudo-second order kinetic model. Intraparticle diffusion affects 4-aminophenol and 4-chlorophenol uptake. Sorption studies carried out using industrial wastewater samples containing phenolic compounds show that there is significant potential for Cr-bentonite as an adsorbent material for phenollic compounds removal from aqueous solutions.
Guojun Zhang and Jessica Xu
H. Zheng et al., "Experimental Investigation on Adsorptive Removal of Phenolic Compounds from Aqueous Solution by Cr-Bentonite", Advanced Materials Research, Vols. 160-162, pp. 163-170, 2011