Forward Osmosis: Past, Present, and Future Hopes

Forward Osmosis (FO), a novel desalination technology, is gaining popularity. Draw solutions generate an osmotic pressure gradient to help water penetrate a semipermeable membrane during FO. Like reverse osmosis, the membrane removes dissolved contaminants. Highly soluble solutes in the draw solution can be reused. With the right membrane and draw solution, FO can deliver cost-effective, high-recovery, foul-resistant desalination. Membrane research has increased interest in engineered osmosis applications, notably reverse osmosis, in recent decades. FO has garnered scholarly attention for five years. Plants and trees use osmosis to extract water from the soil with little energy. Food processing, wastewater treatment, desalination, and seawater and brackish water cleansing utilize FO. Even with these challenges, FO research continues worldwide. These steps are needed to commercialize FO, which will join existing desalination methods if the pilot test succeeds. Technological hurdles remain in commercialization. Like reverse osmosis membranes, FO membranes must have good permeability and selectivity. Because of their high solubility, low toxicity, and simplicity of removal, the draw solutions should be designed from scratch. A global forward osmosis research program continues despite these considerable hurdles. Advances are needed for FO to become commercially viable, although a pilot-scale demonstration could compete with traditional desalination plants. The recently proven physical principles and applications of FO, as well as its pros and cons, are discussed in this study.