Comparative adsorptive performance of adsorbents developed from sugar industrial wastes for the removal of melanoidin pigment from molasses distillery spent wash

Abstract

Following the expansion of distillery industries, a large quantity of waste is being released to the environment containing high color-forming chemicals. This study aimed at degrading melanoidin pigment from distillery spent wash by using impregnated Sugarcane bagasse activated carbon (SCBAC) and Modified Bagasse Fly Ash (MBFA) as a comparative study. FTIR has revealed functional groups responsible for adsorption. A broad peak revealing an amorphous structure was observed for SCBAC while crystalline structure was observed in MBFA using XRD. SEM micrograph revealed an irregular macro-porous structure and regular structure for SCBAC and MBFA respectively. In the adsorption, important process parameters were optimized in response to color removal efficiency. At equilibrium, adsorption isotherm models, kinetics, mechanisms, and thermodynamics of the adsorption were studied. Langmuir model and Pseudo-second order result in the best fit for both adsorbents. Thermodynamics study revealed an exothermic process, feasibility, and spontaneity of the adsorption process for both adsorbents.

Keywords

• Distillery spent wash
• Melanoidin
• Sugar cane bagasse activated carbon (SCBAC)
• Modified bagasse fly ash (MBFA)
• Adsorbents