STUDY ON TREATMENT OF DIRECT BLACK 22 USING ZEOLITE

Abstract

This study evaluated the ability of zeolite to adsorb direct black 22 (DB22) in aqueous solution. The results indicate that the adsorption depends on pH, adsorption time and initial concentration of direct black 22. The optimal conditions for the  direct black 22 adsorption are pH level of 4, contact time of 120 and initial direct black 22 concentration of 12,5 g/L (TOC). Under optimal conditions, the maximum adsorption efficiency of 69,48% was achieved. Experimental data were evaluated based on Langmuir and Fruendlich adsorption isotherm models. The kinetics of the adsorption process were evaluated according to the pseudo-first order, pseudo-second order and Elovich kinetic models. The results show that the adsorption process follows the Fruendlich isotherm adsorption model (K_F = 1.486 mg.g^-1). The adsorption kinetics follows the pseudo-first order with the rate constant of 0,0222 min^-1 (k₁ = 0.0222 min^-1).