Method for water purification by direct osmosis and crystallisation of clathrates hydrates

Abstract

A method is disclosed for purifying, by direct osmosis, a first liquid including water and at least one impurity, in which the method comprises the consecutive steps of: contacting the first liquid with a first side of a semi-permeable membrane, a second aqueous liquid containing an osmotic agent being in contact with the second side of the semi-permeable membrane, whereby water is extracted by direct osmosis from the first liquid through the semi-permeable membrane and passes into the second liquid containing the osmotic agent; forming clathrates hydrates of a host molecule in the second liquid containing the osmotic agent into which the water has passed; separating the clathrates hydrates from the second liquid containing the osmotic agent; and dissociating the separated clathrates hydrates to obtain pure water and the host molecule.

Dependencies are inferred from the claim text.