Paper Title
Desorption Studies For the Recovery of Thorium From Loaded Biosorbent (DKSC): Parameter Optimization and Equilibrium Modelling

Abstract
The aim of this work was to verify the reversibility of sorption process for metal recovery and thus the possibility of the desorption process through batch mode. The present study intended for the desorption of thorium from loaded biomass, deoiled karanja seed cake (DKSC) an agro-industrial waste resulted after expelling oil from the seeds. DKSC has been reported to be one of the most efficient biomass with high metal uptake capacity in the biosorption of thorium and the loaded DKSC at optimum conditions in the thorium biosorption studies was chosen as the raw material for desorption studies and was treated with HCl and HNO3 to recover the sorbed thorium and an effective desorptive solution was identified based on the desorption rate (D%). The operational parameters like L/S ratio and desorptive solution concentration were optimized for maximum desorption rate. A maximum of 96% for desorption rate was attained for 1M HCl with L/S ratio 7.The equilibrium studies were performed at optimal conditions and validated with Langmuir and Freundlich isotherm models and the data fitted well with Langmuir model with highest R2 of 0.99.