THERMAL RESPONSIVE DRAW AGENT FOR FORWARD OSMOSIS DESALINATION AND THE FORWARD OSMOSIS DESALINATION METHOD USING THE DRAW AGENT

摘要

PURPOSE: A temperature responsive forward osmosis draw solute and a forward osmosis seawater desalination method using the same are provided to be capable of easy desalination using forward osmosis, easy separation of the draw solute, and separation in low temperatures to provide very high energy efficiency. CONSTITUTION: A temperature responsive forward osmosis draw solute is indicated in the chemical formula 1. In the chemical formula 1, x and y are respectively integers from 0 to 5, both of which are not zero at the same time.R1-R3 are each CH2CH2NHCOCH(CH3); or R1 and R2 are each CH2CH3 , and R3 is CH2CH2NHCO(CH2)2CH3. The forward osmosis seawater desalination method includes following steps; making seawater come into contact with the draw solute through the semi-permeable membrane with a higher concentration of draw solute than seawater.; transferring fresh water in the seawater to the draw solution through the semi-permeable membrane by the forward osmosis; precipitating the draw solution by lowering the temperature of the draw solution below a consolute temperature; and separating the fresh water from the draw solution.