Factorial Optimization and Kinetics of Coal Washery Effluent Coag-Flocculation By Moringa Oleifera Seed Biomass

Abstract

Factorial optimization and kinetics of coal washery effluent (CWE) coag-flocculation by Moringa oleifera seed has been investigated at room temperature based on standard method of bench scale jar test. Moringa oleifera coag-flocculant (MOC) was produced according to work reported by Ghebremichael. A 2 3 full fac-torial central composite design was employed for the experimental design and analysis of results with respect to optimization. The combined effects of pH, dosage and settling time on the particle (turbidity) removal were studied using response surface methodology. Kinetic data generated were confronted with specified kinetic models for the evaluation of functional kinetics parameters. The optimal values of pH, dosage and settling time were recorded at 8400 mg/l and 25 min, respectively. The results of the major kinetic parame-ters recorded are 20.002 l/mg·min, and 0.79 min for order of reaction, coag-flocculation reaction rate con-stant and coagulation period, respectively. The minimum removal efficiency recorded was 95% at 3 mins of coag-flocculation. The results, while re affirming MOC as efficient coag-flocculant, confirmed that theory of perikinetics holds for the studied system at the conditions of the experiment.