Design of batch process for preconcentration and recovery of U(VI) from liquid waste by powdered corn cobs

Sorption of uranium(VI) from aqueous solution onto powdered corn cob has been carried out using batch technique. The maximum removal (98.5%) was obtained at pH 5 and contact time 60 min. Freundlich, Langmuir, Temkin and Dubinin-Radushkevich (D-R) isotherms are used for describing the sorption process. It is found that the Langmuir isotherm appears to be the best fitting model and pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion kinetics models were studied. The results indicate that the process follows the pseudo-second-order kinetics model. As well as the thermodynamic data indicate that the sorption processes is exothermic. The values of enthalpy (ΔH°), mean free energy (E) and activation energy (Ea) indicate that the sorption process is physical sorption. A single stage of batch adsorber has been designed for various volumes using the Langmuir isotherm.