High performance flocculating agent based on partially hydrolysed sodium alginate-g-polyacrylamide

The partial hydrolysis of the sodium alginate-g-polyacrylamide was carried out in alkaline medium. Four grades of partially hydrolysed products were s ynthesized by varying the reaction parameters. The neutralization equivalen t of these products was determined by titrating with standard sodium hydrox ide solution. Flocculation characteristics of all the hydrolysed graft copo lymers and the unhydrolysed sodium alginate-g-polyacrylamide were determine d in 10 wt% iron ore suspensions. The partially hydrolysed product with neu tralization equivalent of 2865 m shows better performance than other partia lly hydrolysed as well as unhydrolysed products in flocculation. The floccu lation performance of the above best performing product was also compared w ith two commercially available flocculants Rishfloc-440 and Magnafloc-1011, as well as with one flocculant developed in our laboratory (amylopectin-g- polyacrylamide) in 10 wt% iron ore suspension. Here also it was found that the polymer with neutralization equivalent 2865 gm shows better performance than others. (C) 2000 Elsevier Science Ltd. All rights reserved.