Osmotic desalination process

An osmotic method for extracting water from an aqueous solution comprising the steps of;

• a. exposing the aqueous solution to a first surface of a semi-permeable membrane;
• b. adjusting the equilibrium of a second solution to increase an amount of ammonium carbamate present in the solution by adding a first gas comprised of ammonia and carbon dioxide, wherein the ammonia is preferentially adsorbed by the second solution, such that the concentration of the second solution is greater than that of the aqueous solution;
• c. exposing the second solution to a second opposed surface of the membrane;
• d. drawing the water from the aqueous solution across the membrane and into the second solution generating a water-enriched solution;
• e. adjusting the equilibrium of the water-enriched solution wherein the water-enriched second solution comprises ammonium bicarbonate to increase the amount of ammonium bicarbonate present in the solution by adding a second gas, comprised of carbon dioxide gas remaining from the first equilibrium adjustment, causing a portion of the ammonium bicarbonate to precipitate out of the water-enriched solution;
• f. filtering the precipitated ammonium bicarbonate out of the water-enriched solution;
• g. recycling the precipitated ammonium bicarbonate to the second solution;
• h. heating the water-enriched solution to decompose the remaining ammonium carbamate and ammonium bicarbonate into ammonia and carbon dioxide to produce potable water;
• and
• i. recycling the ammonia and carbon dioxide, as the first gas.

An osmotic method for extracting a solvent from a first solution comprising the steps of:

• a. exposing the first solution to a first surface of a semi-permeable membrane;
• b. adjusting the equilibrium in a second solution to increase the amount of a soluble species of solute in the second solution by adding a first reagent comprising a mixture of carbon dioxide and ammonia gasses such that the concentration of the second solution is greater than that of the first solution, wherein the second solution comprises a concentrated solution of ammonia and carbon dioxide, ammonium carbonate, ammonium bicarbonate and ammonium carbamate;
• c. exposing the second solution to a second opposed surface of the membrane;
• d. drawing a solvent from the first solution through the membrane and into the second solution to produce a solvent-enriched second solution;
• and
• e. removing soluble species of solute from the solvent-enriched second solution to obtain only the solvent.