Removal of Novacron black dye from aqueous solutions using low cost agricultural waste: Batch and fixed bed study

Abstract

The present study deals with the removal of Novacron Black dye with peanutpeels biomass, a low cost agricultural waste. The batch mode experiments were performed to compare the biosorption potential of selected biosorbent in its native, glutaraldehydetreated and immobilized form. Experiments were conducted as a function of pH, biosorbent dose, contact time, initial dye concentration and temperature. Glutaraldehyde-treated biomass exhibited better biosorption capacity as compared to the native and immobilized peanut peels. Maximum biosorption capacity (37.1 mg/g) of Novacron Black dye by peanut peels was observed at pH 2 using 0.05 g biosorbent. Equilibrium data were analyzed by Langmuir, Freundlich and Temkin isotherm models. Langmuir isotherm model tted very well to the equilibrium data. The kinetic data was modeled using pseudo- rst-order, pseudo-second-order and intra-particle di usion models. Negative values of G depicted the spontaneous nature of biosorption process. Column studies were performed to optimize the bed height, flow rate and initial dye concentration. The results revealed that the best biosorption was achieved at greater bed heights, lower flow rates and higher initial dye concentrations. Bohrat-Adams model tted very well to the column data of Novacron Black dye biosorption onto peanut peels biomass.