A reduction in the use of aluminum (Al)-based flocculants in the treatment of drinking water is considered essential for human health reasons. In this study, a novel composite flocculant, made of carboxymethylpullulan-AlCl3 , is evaluated in a lab-scale, jar test system for the flocculation of kaolin. The results showed that the coagulation efficiency of carboxymethylpullulan-AlCl3 was more effective in reducing turbidity than the solo use of carboxymethylpullulan or AlCl3 . The optimum treatment conditions assessed by a response surface methodology were obtained at pH 6.50, 13.03 mg/L carboxy...