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US3888974A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for hydrogen isotope exchange and concentration between liquid water and hydrogen gas and catalyst assembly therefor

Assignee: Atomic Energy of Canada Ltd AECL
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Filing: 1973-07-13
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Granted: 1975-06-10
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Expires: 1993-07-13
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Abstract

Abstract A bithermal, catalytic, hydrogen isotope exchange process between liquid water and hydrogen gas to effect concentration of the deuterium isotope of hydrogen, wherein liquid water and hydrogen gas are contacted with one another and with at least one catalytically active metal selected from Group VIII of the Periodic Table, the catalyst body has a water repellent, gas and water vapour permeable, organic polymer or resin coating, preferably a fluorinated olefin polymer or silicone resin coating, so that the isotope exchange takes place by two simultaneously occurring, and closely coupled in space, steps namely, using protium (H) and deuterium (D) as the example, HD gas + H2O vapour catalyst H2 gas + HDO vapour

Inventors

  • 👤 William H Stevens

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 18:44
CPC Classifications
C; C01; C01B; C01B5/00; C01B5/02; B; B01; B01D; B01D59/00; B01D59/28; B01D59/32; B01D59/33

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 344 words
A BITHERMAL, CATALYTIC, ISOTOPE EXCHANGE PROCESS FOR HYDROGEN ISOTOPE CONCENTRATION BETWEEN LIQUID WATER AND HYDROGEN GAS, COMPRISING: A. CONTACTING AT A TEMPERATURE IN THE RANGE 15*C TO 70*C, IN A FIRST SECTION LIQUID FEED WATER AND, THE HYDROGEN GAS FROM A SECOND SECTION WITH ONE ANOTHER AND WITH A CATALYST CONSISTING OF AT LEAST ONE CATALYTICALLY ACTIVE METAL SELECTED FROM GROUP VIII OF THE PERIODIC TABLE SO THAT THE DEUTERIUM ISOTOPE OF HYDROGEN IS TRANSFERRED TO AND CONCENTRATED IN THE LIQUID WATER PASSING THROUGH AND LEAVING THE FIRST SECTION ROM THE HYDROGEN GAS PASSING THROUGH AND LEAVING THE FIRST SECTION, IN EITHER COUNTER-CURRENT OR COCURRENT FLOW, B. CONTACTING AT A TEMPERATURE IN THE RANGE 150*C TO 200*C, IN A SECOND SECTION PRESSURIZED TO KEEP WATER LIQUEFIED, THE LIQUID WATER FROM THE FIRST SECTION AND THE HYDROGEN GAS, PASSING TO THE FIRST SECTION, WITH ONE ANOTHER AND WITH A CATALYST CONSISTING OF AT LEAST ONE CATALYTICALLY ACTIVE METAL SELECTED FROM GROUP VIII OF THE PERIODIC TABLE SO THAT THE HYDROGEN ISOTOPE DEUTERIUM IS TRANSFERRED TO AND CONCENTRATED IN THE HYDROGEN LEAVING THE SECOND SECTION FROM THE LIQUID WATER PASSING THROUGH THE SECOND SECTION, AND C. WITHDRAWING FROM BETWEEN THE FIRST AND SECOND SECTIONS PORTION OF THE LIQUID WATER HAVING THE HYDROGEN ISOTOPE DEUTERIUM CONCENTRATED THEREIN OR THE HYDROGEN GAS HAVING THE HYDROGEN ISOTOPE DEUTERIUM CONCENTRATED THEREIN, AND WHEREIN THE IMPROVEMENT COMPRISES: D. THE CATALYST IS PROVIDED IN THE FIRST AND SECOND SECTIONS AS AT LEAST ONE CATALYST ASSEMBLY, AND COMPRISES THE CATALYST AND A SUBSTANTIALLY LIQUID-WATER-REPELLENT ORGANIC RESIN OR POLYMER COATING THEREON, WHICH IS PERMEABLE TO WATER VAPOUR AND HYDROGEN GAS, WHEREBY: E. EACH CATALYST ASSEMBLY CAUSES HYDROGEN ISOTOPE EXCHANGE AND CONCENTRATION TO OCCUR AS FOLLOWS: HD GAS + HEO VAPOUR CATALYST H2 GAS + HDO VAPOUR, AND HDO VAPOUR + H2O LIQUID LIQUID WATER HDO LIQUID + H2O VAPOUR SO THAT DIRECT CONTACT BETWEEN THE CATALYST METAL AND LIQUID WATER AND WETTING OF THE CATALYST IS RETARDED BY THE ORGANIC POLYMER OR RESIN COATING, THEREBY RETARDING POISONING OF THE CATALYST BY THE LIQUID WATER.
Claim 2
Dependent Claim 344 words
A BITHERMAL, CATALYTIC, ISOTOPE EXCHANGE PROCESS FOR HYDROGEN ISOTOPE CONCENTRATION BETWEEN LIQUID WATER AND HYDROGEN GAS, COMPRISING: A. CONTACTING AT A TEMPERATURE IN THE RANGE 15*C TO 70*C, IN A FIRST SECTION LIQUID FEED WATER AND, THE HYDROGEN GAS FROM A SECOND SECTION WITH ONE ANOTHER AND WITH A CATALYST CONSISTING OF AT LEAST ONE CATALYTICALLY ACTIVE METAL SELECTED FROM GROUP VIII OF THE PERIODIC TABLE SO THAT THE DEUTERIUM ISOTOPE OF HYDROGEN IS TRANSFERRED TO AND CONCENTRATED IN THE LIQUID WATER PASSING THROUGH AND LEAVING THE FIRST SECTION ROM THE HYDROGEN GAS PASSING THROUGH AND LEAVING THE FIRST SECTION, IN EITHER COUNTER-CURRENT OR COCURRENT FLOW, B. CONTACTING AT A TEMPERATURE IN THE RANGE 150*C TO 200*C, IN A SECOND SECTION PRESSURIZED TO KEEP WATER LIQUEFIED, THE LIQUID WATER FROM THE FIRST SECTION AND THE HYDROGEN GAS, PASSING TO THE FIRST SECTION, WITH ONE ANOTHER AND WITH A CATALYST CONSISTING OF AT LEAST ONE CATALYTICALLY ACTIVE METAL SELECTED FROM GROUP VIII OF THE PERIODIC TABLE SO THAT THE HYDROGEN ISOTOPE DEUTERIUM IS TRANSFERRED TO AND CONCENTRATED IN THE HYDROGEN LEAVING THE SECOND SECTION FROM THE LIQUID WATER PASSING THROUGH THE SECOND SECTION, AND C. WITHDRAWING FROM BETWEEN THE FIRST AND SECOND SECTIONS PORTION OF THE LIQUID WATER HAVING THE HYDROGEN ISOTOPE DEUTERIUM CONCENTRATED THEREIN OR THE HYDROGEN GAS HAVING THE HYDROGEN ISOTOPE DEUTERIUM CONCENTRATED THEREIN, AND WHEREIN THE IMPROVEMENT COMPRISES: D. THE CATALYST IS PROVIDED IN THE FIRST AND SECOND SECTIONS AS AT LEAST ONE CATALYST ASSEMBLY, AND COMPRISES THE CATALYST AND A SUBSTANTIALLY LIQUID-WATER-REPELLENT ORGANIC RESIN OR POLYMER COATING THEREON, WHICH IS PERMEABLE TO WATER VAPOUR AND HYDROGEN GAS, WHEREBY: E. EACH CATALYST ASSEMBLY CAUSES HYDROGEN ISOTOPE EXCHANGE AND CONCENTRATION TO OCCUR AS FOLLOWS: HD GAS + HEO VAPOUR CATALYST H2 GAS + HDO VAPOUR, AND HDO VAPOUR + H2O LIQUID LIQUID WATER HDO LIQUID + H2O VAPOUR SO THAT DIRECT CONTACT BETWEEN THE CATALYST METAL AND LIQUID WATER AND WETTING OF THE CATALYST IS RETARDED BY THE ORGANIC POLYMER OR RESIN COATING, THEREBY RETARDING POISONING OF THE CATALYST BY THE LIQUID WATER.
Claim 3
Dependent Claim 23 words
A process according to claim 1, wherein the hydrogen from the first section is recirculated through the second section to the first section.
Claim 4
Dependent Claim 78 words
A process according to claim 1, wherein each catalyst assembly comprises a catalyst support, the catalyst and the substantially liquid-water-repellent organic polymer or resin coating thereon, the catalyst support consists of at least one material selected from the group carbon, graphite, charcoal, alumina, magnesia, silica, silica gel, chromia, molybdenum oxide, tungstic oxide, nickel oxide, kieselguhr, and metal substrate, and the catalyst is at least one metal selected of the group consisting of Pt, Rh, Ir, Pd and Ni.
Claim 5
Dependent Claim 61 words
A process according to claim 3, wherein for each catalyst assembly the total amount of catalyst is not greater than 5 percent by weight of the total weight of that catalyst assembly, and the total amount of the substantially liquid-water-repellent organic polymer or resin coating is not greater than 10 percent by weight of the total weight of that catalyst assembly.
Claim 6
Dependent Claim 47 words
A process according to claim 4, wherein for each catalyst assembly the total amount of catalyst is in the range 0.5 to 1.0 percent by weight of the total weight of that catalyst assembly, and the catalyst is located in an outer surface layer of the support.
Claim 7
Dependent Claim 12 words
A process according to claim 1, wherein the coating is a polyfluorocarbon.
Claim 8
Dependent Claim 19 words
A process according to claim 1, wherein the coating is a polytetrafluoroethylene having a fibrous network or mesh structure.
Claim 9
Dependent Claim 44 words
A process according to claim 7, wherein said polytetrafluoroethylene is applied to said catalyst as a colloidal suspension, dispersing liquid is evaporated to leave particles of the polytetrafluoroethylene on the catalyst, and the particles are sintered to form the fibrous network, or mesh structure.
Claim 10
Dependent Claim 12 words
A process according to claim 1, wherein the coating is a silicone.
Claim 11
Dependent Claim 12 words
A process according to claim 9, wherein said silicone comprises a polysiloxane.
Claim 12
Dependent Claim 25 words
A process according to claim 10, wherein said polysiloxane is a polyalkylsiloxane, having a minor amount of substituent groups selected from hydroxyl, methoxyl and ethoxyl.
Claim 13
Dependent Claim 36 words
A process according to claim 10, wherein the coating comprises a polyalkylsiloxane, having a minor amount of substituent groups selected from hydroxyl, methoxyl, and ethoxyl and including substituents selected from ethyl, propyl, isopropyl and t-butyl groups.
Claim 14
Dependent Claim 22 words
A process according to claim 9, wherein the coating is from about 1 to 10 percent by weight of said catalyst support.
Claim 15
Dependent Claim 22 words
A process according to claim 9, wherein the coating is from about 2 to 5 percent by weight of the catalyst support.
Claim 16
Dependent Claim 20 words
A process according to claim 9, wherein the coating is from about 10 3 to 10 1 microns average thickness.

References Cited (Backward Citations)

US3681257A Cited
US3681021A Cited
US3695841A Cited
US3789112A Cited
US3711598A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-06-09 1978-12-09 1979-06-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-06-09 1982-12-09 1983-06-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-06-09 1986-12-09 1987-06-10 $7700.00 Window Closed / Lapsed

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