Application of synthetic poly(DADM) flocculants for dye wastewater treatment

Poly(DADM) flocculants were synthesized and applied for the removal of color, turbidity and organic materials from dye wastewater. The effect of poly(DADM) on color removal was investigated by comparing two treatments: (i) alum alone and (ii) alum/poly(DADM) in combination. The effects of poly(DADM) flocculant, poly(DADM) concentration, poly(DADM) types and pH on the removal efficiency of coloring materials were investigated. Poly(DADM) flocculants were highly efficient in the removal of color and turbidity from dye wastewater. Compared to treatment with alum alone, the addition of a small amount of poly(DADM) (25 mg l(-1)) reduced alum dosage by 50% while improving color removal efficiency. Highly efficient color removal was obtained in wide pH ranges by adding poly(DADM) as a flocculant. Our results indicate that the use of poly(DADM) flocculant is cost effective in dye wastewater treatment by reducing sludge production and the dosage of inorganic coagulant. Effects of zeta potential were also investigated.