US3909449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for the production of activated carbon spheres
Assignee: Kureha Corp
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Filing: 1974-04-24
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Granted: 1975-09-30
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Expires: 1994-04-24
Abstract
Abstract Spheres of activated carbon are obtained by melting and mixing 100 parts by weight of pitch with 10 to 50 parts by weight of an aromatic solvent compatible with said pitch and 0.01 to 1 part by weight of a metal compound, molding the resultant molten mixture to form a plurality of spheres, immersing the formed spheres in an organic solvent which is compatible with said aromatic solvent and destitute of affinity for said pitch to extract said aromatic solvent from said spheres, infusibilizing the resultant porous pitch spheres having micro-pores and thereafter activating the porous pitch spheres in an atmosphere of ammonia gas at the temperature of 550 to 1000*C. The activated carbon spheres thus produced are particularly useful as activated carbon for the desulfurization of a sulfurous acid gas-containing combustion exhaust gas and for treatment of waste liquor from a sulfite pulp process.
Inventors
- 👤 Hirosi Nagai
- 👤 Kunihiko Katori
- 👤 Zenya Shiiki
- 👤 Yasuo Amagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:34
CPC Classifications
B; B01; B01J; B01J21/00; B01J21/18; B01D; B01D53/00; B01D53/02; B01J35/00; B01J35/50; B01J35/51; B01J37/00; B01J37/0009; B01J37/0018; C; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/384
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
A METHOD FOR THE PRODUCTION OF ACTIVATEDD CARBON SPHERES COMPRISING: MELTING A PITCH, MIXING 100 PARTS OF SAID PITCH WITH 10-50 PARTS BY WEIGHT OF AN AROMATIC SOLVENT COMPATIBLE WITH THE PITCH AND 0.001 I 1 PART BY WEIGHT OF A METAL COMPOUND CAPABLE OF CATALYZING A REACTION BETWEEN SAID PITCH AND AMMONIA, SHAPING THE RESULTING MIXTURE INTO SPHERES, IMMERSING SAID SPHERES IN AN ORGANIC SOLVENT COMPATIBLE WITH SAID AROMATIC SOLVENT BUT LACKING AFFINITY FOR SAID PITCH TO EXTRACT THE AROMATIC SOLVENT FROM THE SPHERES, OXIDIZING THE SPHERES TO INFUSIBILIZE THEM, AND CONTACTING SAID SPHERES WITH AMMONIA FAS OR A GASEOUS MIXTURE CONTAINING AMMONIA AND A MEMBER SELECTED FROM THE GROUP CONSISTING OF AIR, OXYGEN, STEAM, NITROGEN AND HYDROGEN AT A TEMPERATURE WITHIN THE RANGE OF 550*-1000*C TO EFFECT A WEIGHT LOSS OF AT LEAST 15%.
Claim 2
Independent Claim
136 words
A METHOD FOR THE PRODUCTION OF ACTIVATEDD CARBON SPHERES COMPRISING: MELTING A PITCH, MIXING 100 PARTS OF SAID PITCH WITH 10-50 PARTS BY WEIGHT OF AN AROMATIC SOLVENT COMPATIBLE WITH THE PITCH AND 0.001 I 1 PART BY WEIGHT OF A METAL COMPOUND CAPABLE OF CATALYZING A REACTION BETWEEN SAID PITCH AND AMMONIA, SHAPING THE RESULTING MIXTURE INTO SPHERES, IMMERSING SAID SPHERES IN AN ORGANIC SOLVENT COMPATIBLE WITH SAID AROMATIC SOLVENT BUT LACKING AFFINITY FOR SAID PITCH TO EXTRACT THE AROMATIC SOLVENT FROM THE SPHERES, OXIDIZING THE SPHERES TO INFUSIBILIZE THEM, AND CONTACTING SAID SPHERES WITH AMMONIA FAS OR A GASEOUS MIXTURE CONTAINING AMMONIA AND A MEMBER SELECTED FROM THE GROUP CONSISTING OF AIR, OXYGEN, STEAM, NITROGEN AND HYDROGEN AT A TEMPERATURE WITHIN THE RANGE OF 550*-1000*C TO EFFECT A WEIGHT LOSS OF AT LEAST 15%.
Claim 3
Dependent Claim
34 words
The method of claim 1 additionally comprising treating said spheres with steam at temperature within the range of 800*-1000*C. subsequent to contact with the oxidizing agent and prior to contact with the ammonia-contacting gas.
Claim 4
Dependent Claim
25 words
The method of claim 1 additionally comprising, subsequent to contacting with ammonia, treating the spheres with steam at a temperature within the range of 800*-1000*C.
Claim 5
Dependent Claim
31 words
The method of claim 1 wherein said aromatic solvent is selected from the groups consisting of benzene, toluene, xylene, naphthalene, tetralin, methylnaphthalene, a naphtha fraction containing naphthalene, and a BTX fraction.
Claim 6
Dependent Claim
34 words
The method of claim 1 wherein said metal compound is selected from the group consisting of sulfides, sulfates, oxides, nitrates and acetates of Fe, Co, Ni, Cu, V, Mn, Cr, Mo, W and Bi.
Claim 7
Dependent Claim
16 words
The method of claim 1 wherein said organic solvent is an alcohol or a paraffinic hydrocarbon.
Claim 8
Dependent Claim
21 words
The method of claim 6 wherein said paraffinic hydrocarbon is selected from the group consisting of hexane, haptane and light naphtha.
Claim 9
Dependent Claim
19 words
The method of claim 6 wherein said alcohol is selected from the group consisting of methanol, ethanol and propanol.
Claim 10
Dependent Claim
12 words
Discrete spheres of activated carbon formed by the method of claim 1.
References Cited (Backward Citations)
US3502427A
Cited
US3617505A
Cited
US3661503A
Cited
US3786134A
Cited
US3775344A
Cited
US3776829A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |