US4221768A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalyst for purifying exhaust and waste gases
Assignee: Nippon Shokubai Co Ltd
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Filing: 1978-04-28
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Granted: 1980-09-09
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Expires: 1998-04-28
Abstract
Abstract A catalyst for purifying exhaust and waste gases, which consists essentially of (A) 30 to 99% by weight of at least one catalytic oxide selected from a binary oxide comprising titanium and silicon and a ternary oxide comprising Ti, Zr and Si, (B) 1 to 70% by weight of a catalytic oxide comprising at least one element selected from the group consisting of V, W, Mo, U, Cu, Fe, Cr, Mn and Ce, and (C) 0 to 50% by weight of a catalytic oxide comprising at least one element selected from the group consisting of Sn, Zn, Pb, Ti, Zr, Ni, Co, Nb, Ta, P, Br, Bi, Sb, alkali metals, and alkaline earth metals.
Inventors
- 👤 Akira Inoue
- 👤 Takehiko Suzuki
- 👤 Koichi Saito
- 👤 Yukio Aoki
- 👤 Tetsuji Ono
- 👤 Takashi Ohara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:06
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9445; B01D53/945; B01J; B01J21/00; B01J21/06; B01J21/08; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
161 words
A process for the selective removal of nitrogen oxides from oxides from exhaust and waste gases containing nitrogen oxides, which comprises contacting the exhaust and waste gases with ammonia at a temperature of from about 150° C. to about 500° C. in the presence of a catalyst which consists essentially of (A) 30 to 99% by weight of at least one solid acid selected from the group consisting of a binary oxide consisting of titanium, silicon and oxygen and a ternary oxide consisting of titanium, zirconium, silicon and oxygen (B) 1 to 70% by weight of a catalytic oxide comprising at least one element selected from the group consisting of vanadium, tungsten, molybdenum, uranium, copper, iron, chromium, manganese and cerium, and (C) 0 to 50% by weight of a catalytic oxide comprising at least one element selected from the group consisting of tin, zinc, lead, titanium, zirconium, nickel, cobalt, niobium, tantalum, phosphorus, boron, bismuth, antimony, alkali metals, and alkaline earth metals.
Claim 2
Dependent Claim
161 words
A process for the selective removal of nitrogen oxides from oxides from exhaust and waste gases containing nitrogen oxides, which comprises contacting the exhaust and waste gases with ammonia at a temperature of from about 150° C. to about 500° C. in the presence of a catalyst which consists essentially of (A) 30 to 99% by weight of at least one solid acid selected from the group consisting of a binary oxide consisting of titanium, silicon and oxygen and a ternary oxide consisting of titanium, zirconium, silicon and oxygen (B) 1 to 70% by weight of a catalytic oxide comprising at least one element selected from the group consisting of vanadium, tungsten, molybdenum, uranium, copper, iron, chromium, manganese and cerium, and (C) 0 to 50% by weight of a catalytic oxide comprising at least one element selected from the group consisting of tin, zinc, lead, titanium, zirconium, nickel, cobalt, niobium, tantalum, phosphorus, boron, bismuth, antimony, alkali metals, and alkaline earth metals.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein the solid acid has a surface area of at least 5 m 2 /g.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein the solid acid has a surface area of 30 to 450 m 2 /g.
Claim 5
Dependent Claim
36 words
The process of claim 1 wherein the solid acid is a binary oxide which consists of 5 to 95 mole% of titanium as TiO 2 and 95 to 5 mole% of silicon as SiO 2 .
Claim 6
Dependent Claim
41 words
The process of claim 1 wherein the solid acid is a ternary oxide which consists of 5 to 95 mole% of titanium plus zirconium as TiO 2 -ZrO 2 , and 95 to 5 mole% of silicon as SiO 2 .
Claim 7
Dependent Claim
21 words
The process of claim 5 in which the ternary oxide has a ZrO 2 content of not more than 30 mole%.
Claim 8
Dependent Claim
17 words
The process of claim 1 wherein the temperature is in the range of 200° to 400° C.
Claim 9
Dependent Claim
27 words
The process of claim 1 wherein the exhaust and waste gases are contacted with the catalyst at a space velocity of 1,000 to 100,000 hr -1 .
Claim 10
Dependent Claim
20 words
The process of claim 8 wherein the space velocity is in the range of 3,000 to 30,000 hr -1 .
Claim 11
Dependent Claim
25 words
The process of claim 1 wherein the ammonia is added in an amount of 0.5 to 3 mol to 1 mol of the nitrogen oxides.
Claim 12
Dependent Claim
14 words
The process of claim 1 wherein the exhaust and waste gases contain sulfur oxides.
Claim 13
Dependent Claim
57 words
The process of claim 1 wherein the exhaust and waste gases comprise 10 to 1,500 ppm of sulfur oxides, 1 to 20% by volume of oxygen, 1 to 15% by volume of carbon dioxide gas, 5 to 15% by volume of steam, 10 to 100 mg/Nm 3 of soot, and 100 to 1,000 ppm of nitrogen oxides.
Claim 14
Dependent Claim
16 words
The process of claim 1 wherein the pressure is from 0.01 to 10 kg/cm 2 .
Claim 15
Dependent Claim
20 words
The process of claim 1 wherein the solid acid (A) is a mixture of the binary oxide and ternary oxide.
Claim 16
Dependent Claim
60 words
The process of claim 14 wherein the binary oxide consists of 5 to 95 mole% of titanium as TiO 2 and 95 to 5 mole% of silicon as SiO 2 and the ternary oxide consists of 5 to 95 mole% of titanium plus zirconium as TiO 2 -ZrO 2 and 95 to 5 mole% of silicon as SiO 2 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-09 | 1984-03-10 | 1984-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-09 | 1988-03-10 | 1988-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-09 | 1992-03-10 | 1992-09-09 | $7700.00 | Window Closed / Lapsed |