Sorption kinetic study on the removal of Basic Blue–9 dye using activated carbon produced from water spinach

Abstract

Batch adsorption experiments were performed to study the removal kinetics of Basic Blue-9 dye from aqueous solution using activated carbon produced from water spinach. The percent removal of dye increased with time and attained equilibrium in 3 hrs and 20 mins for an initial dye concentration of 250 mg/l. Optimum removal of 96% dye was achieved at the equilibrium time of 200 mins. The equilibrium sorption capacity (qe1) obtained from the pseudo-first order linear plot was 2.75 mg/g with a rate constant, K1 of 0.0115 g/ (mg/min. The experimental data was most suitably analyzed by the pseudo- second order model with a regression coefficient (R2) value of 0.9949. The initial sorption rate, ho was found to be 0.095 mg/g min with an equilibrium sorption capacity (qe2) of 4.80 mg/g. The correlation coefficients R2 1 and R2 2, for the first – and second – order equations were all high (>0.97), suggesting the suitability of both models for the experimental data.Keywords: Activated carbon, Basic Blue-9, kinetics, sorption, water spinach.