Preparation of Crosslinking-Grafting Cationic Starch Flocculant and Its Study on Textile Dyes Removal

In the aim of textile printing and dyeing wastewater efficient and environmental friendly treatment, a cross-linked grafted cationic starch flocculant (CGSt) was prepared to study its removal performance of textile dyes. Here in, corn starch (St) was used as raw material, methacryloyloxyethyl trimethyl ammonium chloride and N.N′-methylenebisacrylamide were used as cationization grafting monomer and crosslinking monomer, respectively, and an environmentally friendly Fenton initiation system was adopted. The chemical structure and physicochemical properties of CGSt were characterized FTIR, NMR, XPS, EDS, XRD and SEM. The flocculation performance of CGSt on acid light yellow G, direct lake blue 5B and reactive brilliant blue KE-GN was investigated. The removal rate (RR) of CGSt to acid light yellow G, reactive brilliant blue KE-GN and direct lake blue 5B reaches 97.2%, 96.3% and 97.2%, respectively. CGSt has a wide flocculation window from 5 g/L to 12 g/L. It maintains good flocculation performance in a wide pH range from 4 to 9, and the RR was the highest when pH was 9, which is beneficial for the treatment of textile printing and dyeing wastewater with high alkalinity, complex composition and variable water quality by CGSt.