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US4096096A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for manufacture of catalyst used for reduction of nitrogen oxides

Assignee: Krosaki Harima Corp
•
Filing: 1976-08-09
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Granted: 1978-06-20
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Expires: 1996-08-09
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Abstract

Abstract An excellent catalyst for the reduction of nitrogen oxides is obtained by mixing a specific aluminum-containing substance with a specific iron-containing substance in water and baking the resultant precipitate.

Inventors

  • 👤 Yasuo Nishikawa
  • 👤 Akira Watanabe
  • 👤 Tetsuya Sugimoto
  • 👤 Yasutoshi Mizuta
  • 👤 Yoshio Hatayama

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 11:27
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/70; B01J23/74; B01J23/745; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8621; B01D53/8625; B01D53/8628

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 175 words
A method for the production of a catalyst for use in the reduction of nitrogen oxides, which method comprises: (a) suspending at least one iron-containing substance selected from the group consisting of Fe 2 O 3 , Fe 2 O 3 .nH 2 O, Fe(OH) 2 , Fe(OH) 3 and Fe 3 O 4 .nH 2 O in an aqueous solution consisting essentially of water and at least one aluminum-containing substance selected from the group consisting of alumina sol, alumina gel and water-soluble aluminum salts whereby said aluminum-containing substance deposits on the surface of said iron-containing substance as a precipitate, the ratio of the suspended iron-containing substance to the aluminum-containing substance being 55 to 95 weight percent as Fe 2 O 3 to 5 to 45 weight percent as Al 2 O 3 ; and (b) washing and drying the resultant precipitate; (c) molding the dried precipitate; (d) baking the molded precipitate at a temperature in the range of from 300° to 1000° C to obtain a product consisting essentially of iron oxide and alumina.
Claim 2
Independent Claim 175 words
A method for the production of a catalyst for use in the reduction of nitrogen oxides, which method comprises: (a) suspending at least one iron-containing substance selected from the group consisting of Fe 2 O 3 , Fe 2 O 3 .nH 2 O, Fe(OH) 2 , Fe(OH) 3 and Fe 3 O 4 .nH 2 O in an aqueous solution consisting essentially of water and at least one aluminum-containing substance selected from the group consisting of alumina sol, alumina gel and water-soluble aluminum salts whereby said aluminum-containing substance deposits on the surface of said iron-containing substance as a precipitate, the ratio of the suspended iron-containing substance to the aluminum-containing substance being 55 to 95 weight percent as Fe 2 O 3 to 5 to 45 weight percent as Al 2 O 3 ; and (b) washing and drying the resultant precipitate; (c) molding the dried precipitate; (d) baking the molded precipitate at a temperature in the range of from 300° to 1000° C to obtain a product consisting essentially of iron oxide and alumina.
Claim 3
Dependent Claim 24 words
The method according to claim 1, wherein said water-soluble aluminum salt is aluminum nitrate, aluminum sulfate, aluminum formate or aluminate having alkali metal moiety.
Claim 4
Dependent Claim 30 words
The method of claim 1, wherein aqua ammonia or an aqueous solution of an alkali is added to the mixture in water to neutralize said mixture thereby forming said precipitate.

References Cited (Backward Citations)

US2449295A Cited
US3896049A Cited
US3976745A Cited
US3987146A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-06-19 1981-12-19 1982-06-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-06-19 1985-12-19 1986-06-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-06-19 1989-12-19 1990-06-20 $7700.00 Window Closed / Lapsed

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