An Overview on the Use of Electrolyte Solution as a Strong Osmotic Agent in Forward Osmosis

Abstract

Forward osmosis (FO) has gained attention of people in recent decades due to its magnificent properties andless energy requirements. This paper aims to discuss various characteristics of draw solutes which are differentiated due to their performance and show exceptional results as osmotic agents in FO. Different types of membranes are being selected for different applications according to needs and requirements. Among them, CTA (Cellulose Triacetate Membrane) and TFC (Thin-film composite membrane) membranesare widely used and show higher fluxas compared to others. Responsive draw solute causes remarkable change in osmotic pressure of the diluted solution when exposed to external factors such as pH and temperature. Responsive and Non-responsive draw solutes have advantages and disadvantages on their usage in FO. Comparative study has been done which shows that as compared to the different techniques for purification, FO stands tallest in terms of economic analysis and alsoresults shown by FO are phenomenal. This review targets recent progress, challenges and opportunities concerning the development of appropriate and efficient osmotic agents with low-cost energy recovery to achieve largescale application of FO and its future development.