REMOVAL OF SOLAR RED BA TEXTILE DYE FROM AQUEOUS SOLUTION BY LOW COST BARLEY HUSK: EQUILIBRIUM, KINETIC AND THERMODYNAMIC STUDY

The present study investigates the sorption potential of barley husk for the removal of solar red BA from aqueous solution. Sorption capacity, q (mg/g), of barley husk decreased with increasing initial dye concentration. The sorption equilibrium established within 90 min using 0.10 g biosorbent while it was prolonged to 135 min with increasing amount of biosorbent (0.25-0.50 g). The equilibrium data were fitted to Freundlich and Langmuir isotherms at different biosorbent doses. The results indicated the applicability of Freundlich isotherm at low-biosorbent dose. Pseudo-second-order kinetic model was found to be best fit to the biosorption data with three biosorbent doses. The equilibrium thermodynamic data for the adsorption of the dyes gave Delta G(0) values -79.77 kJ/mol at 303 K indicated the process to be occurred spontaneously at low temperature. FTIR analysis and SEM imaging of biosorbent were also carried out.