A vast array of industrial operations require the separation of a solvent, predominantly water, from a liquid stream. The ultimate objective of the separation may include the concentration of this liquid stream to reduce its volume before further processing, the retention of suspended or dissolved compounds that necessitate specific treatment, or the production of clean water.

Such a separation process implies negligible losses of the feed constituents, in order to maintain the quality of the concentrate or facilitate the processing of the permeate. The engineering application of osmosis, widely known as forward osmosis, is a membrane filtration technology that can provide this type of separation.

Forward osmosis has been intensively investigated over the last decades for a diverse range of potential applications, spanning from desalination, power generation, and treatment of various wastewater streams to the concentration of liquid foods. It has been suggested that forward osmosis can theoretically have a lower operating cost because lower amounts of energy are used for generating the driving force to run the process compared to its main counterpart, reverse osmosis.