Reverse Osmosis
The forced flow of solvent from a concentrated to a dilute solution by applying pressure greater than the osmotic pressure.
Formula / equation
p_applied > π
Unit
atm
In depth
By overwhelming the natural osmotic gradient, reverse osmosis produces pure solvent from a contaminated or saline feed. Seawater desalination requires pressures above about 60 atm, and the process is energy-intensive but far cheaper than distillation for large volumes.
Examples in the real world
Municipal desalination plants; domestic under-sink water purifiers; concentrating fruit juice without heating it.