WATER PURIFICATION METHOD

摘要

The invention relates to a method of obtaining purified water from an impure water source comprising the steps of: (i) contacting the impure water source through a semi-permeable membrane with a higher osmotic potential draw solution containing a field separable osmotic agent, said osmotic agent comprising one or more ionic salts and/or a superparamagnetic nano-particle bound to a hydrophilic polymer; (ii) maintaining the contact for a time sufficient for a net flow of water to take place from the impure water source into the draw solution; and (iii) carrying out magnetic and/or electric field separation of the field separable osmotic agent from the draw solution to obtain purified water. The invention also relates to an apparatus for carrying out this method, and to field separable osmotic agents for use in the method.