REVERSE OSMOSIS
It is a membrane process by which water is separated from saline water. Osmosis is defined as the spontaneous flow of 'water' from dilute to more concentrated solution through a semipermeable membrane. The driving force in this phenomenon is called osmotic pressure . A semipermeable membrane is one which permits only water molecules to pass through it. Examples of semipermeable membranes are cellulose acetate, polyamide, polymide, etc. This natural process can be reversed by applying pressure higher than the osmotic pressure on the concentrated side. Thus the solvent is forced to move from concentrated side to dilute side across the membrane. This principle is known as r everse osmosis. In the reverse osmosis process, the pure water (free from ions) is separated from the contaminated brine water (salty water). This membrane filtration is also called super filtration (or) hyper filtration. For advantages and disadvantages of reverse osmosis refer https://meticulousperspectiv