Oil and water mix and un-mix on demand

Oil and water can for thefirst time be mixed and separated on demand thanks to a new, reversiblesurfactant.The liquid molecule couldprove invaluable in mitigating the environmental damage caused by oil spills.Such a chemical could alsosimplify commercial oil extraction from currently inaccessible deposits. And it would prove equally valuable in the food and cosmeticsindustries, simplifying processes and products which rely on the mixing orseparation of oily and watery components. The genius of the newsurfactant lies in its reversibility. Unlike existing ones, it can be switched"on" or "off" repeatedly. The switches are very simple too:carbon dioxide and air. Bubble carbon dioxidethrough a solution and the surfactant switches on, leading the oil-and-watermix to form an emulsion, explains Philip Jessop at Queen's University in Kingston, Ontario, Canada, who ledthe research team that developed the new surfactant.
To switch it off again, yoububble air through it, and the oil and water separate again.

Source: newscientisttech.comAdded: 2 October 2006