Analysis and optimization of flocculation activity and turbidity reduction in kaolin suspension using pectin as a biopolymer flocculant

摘要

The performance of pectin in turbidity reduction and the optimum condition were determinednusing Response Surface Methodology (RSM). The effect of pH, cation’s concentration, and pectin’sndosage on flocculating activity and turbidity reduction was investigated at three levels andnoptimized by using Box–Behnken Design (BBD). Coagulation and flocculation process werenassessed with a standard jar test procedure with rapid and slow mixing of a kaolin suspensionn(aluminium silicate), at 150 rpm and 30 rpm, respectively, in which a cation e.g. Al3+, acts asncoagulant, and pectin acts as the flocculant. In this research, all factors exhibited significantneffect on flocculating activity and turbidity reduction. The experimental data and modelnpredictions well agreed. From the 3D response surface graph, maximum flocculating activity andnturbidity reduction are in the region of pH greater than 3, cation concentration greater thann0.5mM, and pectin dosage greater than 20 mg/L, using synthetic turbid wastewater within thenrange. The flocculating activity for pectin and turbidity reduction in wastewater is at 99%.