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US4774026A Expired / Lapsed US ⏱️ 0.0 years remaining

Process and apparatus for oxidizing or reducing dissolved substance

Assignee: Hitachi Ltd
•
Filing: 1987-01-22
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Granted: 1988-09-27
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Expires: 2007-01-22
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Abstract

Abstract A dissolved substance contained in a solution is oxidized or reduced by adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the particulate semiconductor photocatalyst to a solution containing a dissolved substance, and irradiating the particulate semiconductor photocatalyst in the solution with an electromagnetic wave having an energy high enough to excite the particulate semiconductor photocatalyst, or by adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the particulate semiconductor photocatalyst to a solution containing a dissolved substance and irradiating the particulate semiconductor photocatalyst in the solution with an electromagnetic wave having an energy high enough to excite the particulate semiconductor photocatalyst and having a wavelength outside the absorption wavelength region of a precursor substance capable of producing an oxidation or reduction reaction-inhibiting substance, whereby (1) ions or complexes are converted to simple substances or to ions or compounds with different valencies, and (2) simple substances, ions, complexes or other compounds are separated and recovered or removed by utilizing its actions and effects.

Inventors

  • 👤 Takehiko Kitamori
  • 👤 Takashi Nishi
  • 👤 Tetsuo Fukasawa
  • 👤 Haruo Fujimori
  • 👤 Akira Sasahira
  • 👤 Yoshihiro Ozawa
  • 👤 Kazumichi Suzuki
  • 👤 Hideo Yusa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:10
CPC Classifications
C; C22; C22B; C22B3/00; C22B3/20; C22B3/44; B; B01; B01J; B01J19/00; B01J19/08; B01J19/12; B01J19/122; B01J19/123; C01; C01F; C01F17/00; C01F17/20; C01F17/253; C01F17/259; C01G; C01G1/00; C01G43/00; C01G55/00; C01G56/00; C01G56/001; C01G56/007; C01G56/008; C02; C02F; C02F1/00; C02F1/72; C02F1/725; G; G21; G21C; G21C19/00; G21C19/42; G21C19/44; G21C19/46; C01P; C01P2004/00; C01P2004/60; C01P2004/61; C01P2004/62; C02F1/30; C02F1/32; C02F2305/00; C02F2305/10; Y; Y02; Y02E; Y02E30/00; Y02E30/30; Y02P; Y02P10/00; Y02P10/20; Y02W; Y02W10/00; Y02W10/30; Y02W10/37; Y02W30/00; Y02W30/50

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 73 words
A proces for oxidizing or reducing a dissolved substance which comprises adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the pariculate semiconductor photocatalyst to a solution containig a dissolved substance and irradiating the particulate semiconductor photocatalyst in the solution with an electromaonetic wave having an energy high enough to excite the pariculate semiconductor photocatalyst and a wavelength subsantially equal to the particle size of the particulate semiconductor photocatalyst.
Claim 2
Dependent Claim 73 words
A proces for oxidizing or reducing a dissolved substance which comprises adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the pariculate semiconductor photocatalyst to a solution containig a dissolved substance and irradiating the particulate semiconductor photocatalyst in the solution with an electromaonetic wave having an energy high enough to excite the pariculate semiconductor photocatalyst and a wavelength subsantially equal to the particle size of the particulate semiconductor photocatalyst.
Claim 3
Dependent Claim 19 words
A process according to claim 1, wherein the particulate semicnductor photocatalyst supports a platinum group element on the surface.
Claim 4
Dependent Claim 22 words
A proces according to claim 1, wherein the dissolved substance is selected from noble metals, heavy metals, transitio metals, and actinide elements.
Claim 5
Dependent Claim 33 words
A process according to claim 1, wherein irradiating the particulate semiconductor photocatalyst produces positive holes and excited electrons which are diffused into said solution causing said oxidizing or reducing of said dissolved substantce.
Claim 6
Dependent Claim 27 words
A process according to claim 4, wherein said water-soluble electron acceptor is added to said solution and said positive holes cause said oxidation of said dissolved substance.
Claim 7
Dependent Claim 27 words
A process according to claim 4, wherein said water-soluble electron donor is added to said solution and said excited electrons cause said reducing of said dissolved substance.
Claim 8
Dependent Claim 18 words
A process according to claim 6, wherein said dissolved substance comprises noble metal ions or noble metal complexes.
Claim 9
Dependent Claim 34 words
A process according to claim 4, wherein said particulate semiconductor photocatalyst is selected from the group consisiting of TiO 2 , SrTiO 3 , CdS, CdSe, Si, SiC, ZnO, GaP and WO 2 .
Claim 10
Dependent Claim 20 words
A process according to claim 4, wherein said particulate semiconductor photocatlyst has a particle size of 0.2 to 1 μm.
Claim 11
Dependent Claim 20 words
A process according to claim 4, wherein said particulate semiconductor photocatalyst has a particle size of 0.4 to 0.6 μm.
Claim 12
Dependent Claim 93 words
A process for oxidizing or reducing a dissolved substance, which comprises adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the particulate semiconductor photocatalyst to a solution containing a dissolved substance and irradiating the particulate semiconductor photocatalyst in the solution with an electromagnetic wave having an energy high enough to excite the particulate semiconductor photocatalyst and having a wavelength outside the absorption wavelength region of a precursor substance capable of producing an oxidation or reduction reaction-inhibiting substance and substantially equal to the particle size of the particulate semiconductor photocatalyst.
Claim 13
Dependent Claim 93 words
A process for oxidizing or reducing a dissolved substance, which comprises adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the particulate semiconductor photocatalyst to a solution containing a dissolved substance and irradiating the particulate semiconductor photocatalyst in the solution with an electromagnetic wave having an energy high enough to excite the particulate semiconductor photocatalyst and having a wavelength outside the absorption wavelength region of a precursor substance capable of producing an oxidation or reduction reaction-inhibiting substance and substantially equal to the particle size of the particulate semiconductor photocatalyst.
Claim 14
Dependent Claim 19 words
A process according to claim 11, wherein the particulate semiconductor photocatalyst supports a platinum group element on the surface.
Claim 15
Dependent Claim 22 words
A process according to claim 12, wherein the dissolved substance is selected from noble metals, heavy metals, transition metals, and actinide elements.
Claim 16
Dependent Claim 33 words
A process according to claim 11, wherein irradiating the particulate semiconductor photocatalyst produces positive holes and excited electrons which are diffused into said solution causing said oxidizing or reducing of said dissolved substance.
Claim 17
Dependent Claim 27 words
A process according to claim 14, wherein said water-soluble electron acceptor is added to said solution and said positive holes caus said oxidation of said dissolved substance.
Claim 18
Dependent Claim 27 words
A process according to claim 14, wherein said water-soluble electron donor is added to said solution and said excited electrons cause said reducing of said dissolved substance.
Claim 19
Dependent Claim 18 words
A process according to claim 16, wherein said dissolved substance comprises noble metal ions or noble metal complexes.
Claim 20
Dependent Claim 34 words
A process according to claim 14, wherein said particulate semiconductor photocatalyst is selected from the group consisting of TiO 2 , SrTiO 3 , CdS, CdSe, Si, SiC, ZnO, GaP and WO 2 .
Claim 21
Dependent Claim 20 words
A process according to claim 14, wherein said particulate semicondutor photocatalyst has a particle size of 0.2 to 1 μm.
Claim 22
Dependent Claim 20 words
A process according to claim 14, wherein said particulate semiconductor photocatalyst has a particle size of 0.4 to 0.6 μm.
Claim 23
Dependent Claim 93 words
A process for oxidizing or reducing a dissolved substance, which comprises adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the particulate semiconductor photocatalyst to a solution containing a dissolved substance, and irradiating the particulate semiconductor photocatalyst in the solution with a laser beam having an energy high enough to excite the particulate semiconductor photocatalyst and having a wavelength outside the absorption wavelength region of a precursor substance capable of producing an oxidation or reduction reaction-inhibiting substance and substantially equal to the particle size of the particulate semiconductor photocatalyst.
Claim 24
Dependent Claim 93 words
A process for oxidizing or reducing a dissolved substance, which comprises adding a particulate semiconductor photocatalyst and a water-soluble electron acceptor or donor for the particulate semiconductor photocatalyst to a solution containing a dissolved substance, and irradiating the particulate semiconductor photocatalyst in the solution with a laser beam having an energy high enough to excite the particulate semiconductor photocatalyst and having a wavelength outside the absorption wavelength region of a precursor substance capable of producing an oxidation or reduction reaction-inhibiting substance and substantially equal to the particle size of the particulate semiconductor photocatalyst.
Claim 25
Dependent Claim 19 words
A process according to claim 21, wherein the particulate semiconductor photocatalyst support a platinum group element on the surface.
Claim 26
Dependent Claim 43 words
A process according to claim 21, wherein the solution is a waste solution resulting from dissolution of spent nuclear fuel in nitric acid in a nuclear fuel reprocessing step and containing Ru element and being substantially separated and freed from nuclear fuel components.
Claim 27
Dependent Claim 33 words
A process according to claim 23, wherein the waste solution is waste solution resulting from the dissolution of spent nuclear fuel in nitric acid before said waste solution is solidified by glass solidification.
Claim 28
Dependent Claim 33 words
A process according to claim 21, wherein irradiating the particulate semiconductor photocatalyst produces positive holes and excited electrons which are diffused into said solution causing said oxidizing or reducing of said dissolved substance.
Claim 29
Dependent Claim 27 words
A process according to claim 25, wherein said water-soluble electron acceptor is added to said solution and said positive holes cause said oxidation of said dissolved substance.
Claim 30
Dependent Claim 27 words
A process according to claim 25, wherein said water-soluble electron donor is added to said solution and said excited electrons cause said reducing of said dissolved substance.
Claim 31
Dependent Claim 18 words
A process according to claim 27, wherein said dissolved substance comprises noble metal ions or noble metal complexes.
Claim 32
Dependent Claim 34 words
A process according to claim 25, wherein said particulate semiconductor photocatalyst is selected from the group consisting of TiO 2 , SrTiO 3 , CdS, CdSe, Si, SiC, ZnO, GaP and WO 2 .
Claim 33
Dependent Claim 20 words
A process according to claim 25, wherein said particulate semiconductor photocatalyst has a particle size of 0.2 to 1 μm.
Claim 34
Dependent Claim 20 words
A process according to claim 25, wherein said particulate semiconductor photocatalyst has a particle size of 0.4 to 0.6 μm.

References Cited (Backward Citations)

US3085952A Cited
DE2146262A1 Cited
US3901806A Cited
DE2929122A1 Cited
JPS5767002A Cited
US4619838A Cited
US4451342A Cited
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JPS6050172A Cited
US4571290A Cited
US4655891A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-09-27 1992-03-28 1992-09-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-09-27 1996-03-28 1996-09-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-09-27 2000-03-28 2000-09-27 $7700.00 Window Closed / Lapsed

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