Hydroacid complexes: a new class of draw solutes to promote forward osmosis (FO) processes.

A new class of draw solutes from hydroacid complexes is presented. With hydroacid complexes as draw solutes in FO, superior performance is achieved in terms of high water fluxes and negligible reverse solute fluxes. The characteristics of expanded configurations, abundant hydrophilic groups and ionic species are essential for hydroacid complexes as competent draw solutes.