%J Water, Air, and Soil Pollution
%L scholars2258
%O cited By 25
%N 1-4
%R 10.1007/s11270-010-0503-0
%D 2011
%K Adsorption kinetics; Aqueous solutions; Batch adsorption experiments; Castor hull; Castor seeds; Commercial activated carbons; Comparative studies; Contact time; Correlation coefficient; Equilibrium adsorption; Experimental parameters; Intraparticle diffusion models; Kinetic experiment; Langmuir and freundlich adsorption; Langmuir models; Metal ion concentration; Monolayer adsorption; Per unit; Pseudo second order kinetics; Rapid adsorption; Separation factors; Solution pH; Three-step process; Transition phase; Zinc adsorption, Activated carbon; Adsorption isotherms; Dyes; Metal ions; Metals; Monolayers; Phase transitions; Rate constants; Solutions; Zinc, Adsorption, activated carbon; zinc ion, activated carbon; adsorption; aqueous solution; reaction kinetics; zinc, adsorption; aqueous solution; article; chemical reaction kinetics; correlation coefficient; effluent; heavy metal removal; isotherm; pH; Ricinus communis
%X The effects of various experimental parameters on adsorption of Zn 2+ metal ion from its aqueous solution by castor seed hull and also by activated carbon have been investigated using batch adsorption experiments. It has been found that the amount of zinc adsorbed per unit mass of the hull increases with the initial metal ion concentration, contact time, solution pH and with the amount of the adsorbent. Kinetic experiments clearly indicate that adsorption of zinc on both castor hull and activated carbon is a three-step process-a rapid adsorption of the metal ion, a transition phase, and an almost flat plateau. This has also been confirmed by the intraparticle diffusion model. It has also been found that the zinc adsorption process followed pseudo-second order kinetics. The kinetic parameters including rate constants have been determined at different initial metal ion concentration, pH, amount, and type of adsorbent, respectively. The Langmuir and Freundlich adsorption isotherm models have been used to interpret the equilibrium adsorption data. The Langmuir model yields better correlation coefficients. The monolayer adsorption capacities (q m ) of castor hull and activated carbon have been compared with those for others reported in the literature. The value of separation factor (R L ) derived from the Langmuir model gives an indication of favorable adsorption. Finally, from comparative studies, it has been found that castor hull is a potentially attractive adsorbent as compared to commercial activated carbon for the removal of zinc from aqueus effluents. © 2010 Springer Science+Business Media B.V.
%P 609-620
%A M. Mohammod
%A T.K. Sen
%A S. Maitra
%A B.K. Dutta
%V 215
%T Removal of Zn2+ from aqueous solution using castor seed hull