Claims
- 1. A process for treating water to remove at least one organic material therefrom, comprising the steps of
- a. contacting a synthetic organic polymeric adsorbent with a stream of water containing said organic material under conditions such that said organic material is adsorbed as an adsorbate on said synthetic organic polymeric adsorbent;
- b. then contacting said synthetic organic polymeric adsorbent with said organic material adsorbed thereon with a supercritical fluid which is a solvent for said organic material to desorb said organic material and to dissolve it in said supercritical fluid, thereby to render said adsorbent capable of adsorbing an additional quantity of said organic material, said supercritical fluid during said contacting being at a temperature between about 1.01 and about 1.3 times its critical temperature in degrees K and at a pressure above its critical pressure;
- c. separating said supercritical fluid with said dissolved organic material from said adsorbent;
- d. subjecting said supercritical fluid containing said organic material dissolved therein to physical treatment which renders said fluid a nonsolvent for said organic material thereby to form a two-phase system comprising said fluid in a nonsolvent state and said organic material;
- e. separating the resulting two-phase system into nonsolvent state fluid and organic material; and
- f. subjecting said nonsolvent state fluid subsequent to said separating step to a physical treatment which converts it to a solvent state supercritical fluid making it a solvent for said organic material.
- 2. A process in accordance with claim 1 wherein said synthetic organic polymeric adsorbent is a polymer of styrene, a copolymer of styrene and divinylbenzene, or a polymer containing an acrylic ester, trimethylolpropane trimethacrylate or trimethylolpropane dimethacrylate.
- 3. A process in accordance with claim 1 wherein said supercritical fluid is carbon dioxide.
- 4. A process in accordance with claim 1 wherein said supercritical fluid used in step (b) is at a temperature between about 1.01 and 1.1 times the critical temperature in degrees K of said fluid.
- 5. A process in accordance with claim 1 wherein said supercritical fluid is carbon dioxide at a temperature between about 34.degree. C and 65.degree. C.
- 6. A process in accordance with claim 1 wherein said physical treatment of step (d) comprises decreasing the pressure of said supercritical fluid.
- 7. A process in accordance with claim 6 wherein said physical treatment of step (f) comprises compressing said nonsolvent state fluid to a pressure which is greater than said critical pressure.
- 8. A process in accordance with claim 6 wherein said decreasing of said pressure is accomplished by expansion accompanied by a concomitant decreasing of the temperature of said supercritical fluid.
- 9. A process in accordance with claim 8 wherein said physical treatment of step (f) comprises compressing said nonsolvent state fluid thereby to heat said fluid and to raise it to a pressure which is greater than said critical pressure and effecting indirect heat exchange between said nonsolvent state fluid and the resulting compressed fluid thereby to decrease the temperature of said compressed fluid and to form said solvent state supercritical fluid.
- 10. A process in accordance with claim 1 wherein said physical treatment of step (d) comprises changing the temperature of said supercritical fluid in one direction and said physical treatment of step (f) comprises changing the temperature of said nonsolvent state fluid in a direction opposite to that of step (d).
- 11. A process in accordance with claim 1 wherein the physical treatment of step (d) and the separating of step (e) are carried out in stages thereby to effect the separation of more than one fraction of said adsorbate.
- 12. A process in accordance with claim 1 including the step of chemically reacting said adsorbate in said supercritical fluid with a reactant for said adsorbate introduced therein.
- 13. A process in accordance with claim 12 wherein said step of chemically reacting said adsorbate is carried out prior to said physical treatment of step (d).
- 14. A process in accordance with claim 12 wherein said step of chemically reacting said adsorbate is carried out subsequent to said physical treatment of step (d).
- 15. A process in accordance with claim 1 wherein said water comprises the bleaching effluent from a pulp mill and said organic material comprises color bodies.
- 16. A process in accordance with claim 1 wherein said water comprises a stream containing waste dyestuffs as said organic material.
- 17. A process in accordance with claim 1 wherein said water is a wastewater stream containing pesticides, insecticides, detergents or explosives as said organic material.
- 18. A process in accordance with claim 1 wherein said water contains a biological material as said organic material.
- 19. A process for desorbing an adsorbate from a synthetic organic polymeric adsorbent, characterized by contacting said synthetic organic polymeric adsorbent with said adsorbate adsorbed thereon with a supercritical fluid which is a solvent for said adsorbate to desorb said adsorbate from said synthetic organic polymeric adsorbent and to dissolve it in said supercritical fluid thereby to render said adsorbent capable of adsorbing an additional quantity of said adsorbate; the temperature of said supercritical fluid ranging between about 1.01 and 1.3 times the critical temperature in degrees K of said fluid and the pressure being above the critical pressure of said fluid.
- 20. A process in accordance with claim 19 wherein said supercritical fluid is carbon dioxide.
- 21. A process in accordance with claim 19 wherein said supercritical fluid ranges between about 1.01 and 1.1 times the critical temperature in degrees K of said fluid.
- 22. A process in accordance with claim 21 wherein said supercritical fluid is carbon dioxide.
- 23. In a process for treating wastewater in which at least one organic material is adsorbed on a synthetic organic polymeric adsorbent and said synthetic organic polymeric adsorbent is periodically regenerated by desorbing said organic material therefrom, the improvement comprising regenerating said synthetic organic polymeric adsorbent by contacting said adsorbent with said organic material with a supercritical fluid which is a solvent for said organic material to desorb said organic material from said adsorbent and to dissolve it in said supercritical fluid thereby to render said adsorbent capable of adsorbing an additional quantity of said organic material; the temperature of said supercritical fluid ranging between about 1.01 and 1.3 times the critical temperature in degrees K of said fluid and the pressure being above the critical pressure of said fluid.
- 24. A process in accordance with claim 23 wherein said supercritical fluid is carbon dioxide.
Parent Case Info
This application is a continuation-in-part of my application Ser. No. 512,124 filed Oct. 4, 1974.
US Referenced Citations (7)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
512124 |
Oct 1974 |
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