Application of poly (4-styrenesulfonic acid-co-maleic acid) sodium salt as novel draw solute in forward osmosis for dye-containing wastewater treatment

The selection of proper draw solution is crucial to guarantee a high-performance FO process with minimal reverse solute flux and easy draw solution recovery. In this study, a polyelectrolyte salt-poly (4-styrenesulfonic acid-co-maleic acid) sodium (P(SSA-co-MA)-Na), was applied as draw solutes in FO process. The effects of the chemical structure, osmotic pressure, viscosity of the draw solution and the resulted FO performance are investigated systematically. Because of the high osmotic pressure of the solution and the large molecular size, P(SSA-co-MA)Na exhibits a higher water flux and a lower salt leakage as compared with polyacrylic acid sodium salts (PAA-Na) and poly (sodium-4-styrenesulfonate) (PSS-Na). Especially, a high water flux of about 15 LMH and a significantly lower solute leakage of about 0.04 gMH can be generated with 025 g/ml P(SSA-co-MA)-Na draw solution and de ionized water as the feed solution under PRO mode. The potential of P(SSA-co-MA)-Na draw solution is further evaluated for water recovery from the dye-containing wastewater via FO process. In addition, the diluted P(SSA-coMA)-Na can also be regenerated by nanofiltration (NF) system. The overall performance proves that P(SSA-coMA)-Na as draw solute in FO process is applicable. (C) 2017 Elsevier B.V. All rights reserved.