Systems and methods for water desalination using thermo-responsive ionic liquids regenerated by solar energy

Abstract

This disclosure provides systems, methods, and apparatus related to water desalination. In one aspect, a method includes generating a diluted draw solution using forward osmosis. Wastewater is on a first side of an osmotic membrane and a draw solution is on a second side of the osmotic membrane. The draw solution comprises a mixture of water and an ionic liquid. Water in the wastewater diffuses across the osmotic membrane to the draw solution to form the diluted draw solution. The diluted draw solution is heated using a photonic heater to a temperature above a lower critical solution temperature (LCST) of the ionic liquid to phase separate the diluted draw solution into the ionic liquid and treated water.