US4490160A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for enrichment of nitrogen in air by the method of adsorption and a carbonaceous adsorbent suitable therefor
Assignee: DIRECTOR-GENERAL OF AGENCY OF INDUSTRIAL SCIENCE AND TECHNOLOGY A CORP OF JAPAN
•
Filing: 1983-09-06
•
Granted: 1984-12-25
•
Expires: 2003-09-06
Abstract
Abstract The invention provides an improvement in the method for the enrichment of nitrogen in air by the method of selective adsorption of oxygen in air on a carbonaceous adsorbent material. The improvement comprises the use of an adsorbent material prepared in a specific manner in which a pulverized coal char is blended with a limited amount of a sulfite pulp waste liquor and the blend is shaped into granules or pellets followed by carbonization at 300 DEG to 450 DEG C. for 1 to 2 hours. An enriched nitrogen gas containing 1% by volume or less of oxygen can readily be obtained by passing air through a column filled with the adsorbent material.
Inventors
- 👤 Nakaji Yuki
- 👤 Hiroshi Kitagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:27
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/20; B01D; B01D53/00; B01D53/02; Y; Y10; Y10S; Y10S95/00; Y10S95/90
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
154 words
In a method for the enrichment of nitrogen in air by the selective adsorption of oxygen on a carbonaceous adsorbent material, the improvement that the carbonaceous adsorbent material is prepared by the procedure comprising the steps of: (a) charring a non-coking coal at a temperature in the range from 600° to 700° C. for 1 to 2 hours in an atmosphere lean in oxygen to give a coal char; (b) pulverizing the coal char; (c) blending the pulverized coal char with a sulfite pulp waste liquor in an amount in the range from 10 to 20% by weight as solid based on the pulverized coal char; (d) shaping the blend of the pulverized coal char and the sulfite pulp waste liquor into pellets or granules; and (e) carbonizing the pellets or granules by heating in a non-oxzidizing atmosphere at a temperature in the range from 300° to 420° C. for 1 to 2 hours.
Claim 2
Dependent Claim
154 words
In a method for the enrichment of nitrogen in air by the selective adsorption of oxygen on a carbonaceous adsorbent material, the improvement that the carbonaceous adsorbent material is prepared by the procedure comprising the steps of: (a) charring a non-coking coal at a temperature in the range from 600° to 700° C. for 1 to 2 hours in an atmosphere lean in oxygen to give a coal char; (b) pulverizing the coal char; (c) blending the pulverized coal char with a sulfite pulp waste liquor in an amount in the range from 10 to 20% by weight as solid based on the pulverized coal char; (d) shaping the blend of the pulverized coal char and the sulfite pulp waste liquor into pellets or granules; and (e) carbonizing the pellets or granules by heating in a non-oxzidizing atmosphere at a temperature in the range from 300° to 420° C. for 1 to 2 hours.
Claim 3
Dependent Claim
29 words
The improvement as claimed in claim 1 wherein the pulverized coal char has a particle size distribution to pass a screen of 100 mesh openings by the Tyler standard.
Claim 4
Independent Claim
119 words
A method for the enrichment of nitrogen in air by the selective adsorption of oxygen on a carbonaceous adsorbent material comprising preparing a carbonaceous adsorbent material by the steps of (a) charring a non-coking coal at a temperature in the range from 600° to 700° C. for 1 to 2 hours in an atmosphere lean in oxygen to give a coal char; (b) pulverizing the coal char; (c) blending the pulverized coal char with a sulfite pulp waste liquor in an amount in the range from 10 to 20% by weight as solid based on the pulverized coal char; (d) shaping the blend of the pulverized coal char and the sulfite pulp waste liquor into pellets or granules; and
Claim 5
Independent Claim
119 words
A method for the enrichment of nitrogen in air by the selective adsorption of oxygen on a carbonaceous adsorbent material comprising preparing a carbonaceous adsorbent material by the steps of (a) charring a non-coking coal at a temperature in the range from 600° to 700° C. for 1 to 2 hours in an atmosphere lean in oxygen to give a coal char; (b) pulverizing the coal char; (c) blending the pulverized coal char with a sulfite pulp waste liquor in an amount in the range from 10 to 20% by weight as solid based on the pulverized coal char; (d) shaping the blend of the pulverized coal char and the sulfite pulp waste liquor into pellets or granules; and
Claim 6
Dependent Claim
41 words
(e) carbonizing the pellets or granules by heating in a non-oxidizing atmosphere at a temperature in the range from 300° to 420° C. for 1 to 2 hours; and passing air to be nitrogen enriched through the resulting pellets or granules.
Claim 7
Dependent Claim
41 words
(e) carbonizing the pellets or granules by heating in a non-oxidizing atmosphere at a temperature in the range from 300° to 420° C. for 1 to 2 hours; and passing air to be nitrogen enriched through the resulting pellets or granules.
References Cited (Backward Citations)
US3996108A
Cited
JPS5258093A
Cited
US4124529A
Cited
US4233117A
Cited
JPS537702A
Cited
US4165220A
Cited
US4264339A
Cited
US4156595A
Cited
US4415340A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |