Patent US4409125A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4409125A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for producing activated fibrous carbon

Assignee: Takeda Pharmaceutical Co Ltd
•
Filing: 1979-06-22
•
Granted: 1983-10-11
•
Expires: 1999-06-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract PCT No. PCT/JP79/00160 Sec. 371 Date Feb. 22, 1980 Sec. 102(e) Date Jul. 2, 1979 PCT Filed Jun. 22, 1979.A process for producing activated fibrous carbon comprises carbonizing and activating vegetable fibers in the presence of at least a member selected from the group consisting of ammonium salts of inorganic acids, nitric acid and boric acid and zinc chloride of about 5 to 80 parts by weight per 100 parts by weight of the vegetable fibers. The process increases remarkably a yield of activated fibrous carbon and therefore permits the supply of activated fibrous carbon at by far reduced costs as compared with the conventional process, and the resulting activated carbon shows superior adsorption capability and flexibility.

Inventors

  • 👤 Hiroshi Nishino
  • 👤 Masayuki Suzuki
  • 👤 Hideo Hirota

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 22:32
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/16; C; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/382

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 95 words
A process for producing activated fibrous carbon, which comprises carbonizing vegetable fibers in the presence of at least one member selected from the group consisting of ammonium salts of inorganic acids, nitric acid and boric acid and then activating the carbonized material, in the presence of 30 to 200 parts by weight of zinc chloride on the basis of 100 parts by weight of the carbonized material, in an atmosphere of nitrogen gas or a combustion gas from heavy oil, light oil or kerosene, at 350° C. to 750° C. for 0.25 to 2 hours.
Claim 2
Dependent Claim 95 words
A process for producing activated fibrous carbon, which comprises carbonizing vegetable fibers in the presence of at least one member selected from the group consisting of ammonium salts of inorganic acids, nitric acid and boric acid and then activating the carbonized material, in the presence of 30 to 200 parts by weight of zinc chloride on the basis of 100 parts by weight of the carbonized material, in an atmosphere of nitrogen gas or a combustion gas from heavy oil, light oil or kerosene, at 350° C. to 750° C. for 0.25 to 2 hours.
Claim 3
Dependent Claim 18 words
A process as claimed in claim 1, wherein the carbonization temperature is at about 250° to 450° C.
Claim 4
Dependent Claim 17 words
A process as claimed in claim 1 wherein the ammonium salt of inorganic acid is ammonium chloride.

References Cited (Backward Citations)

US3847833A Cited
CA983225A Cited
US3969268A Cited
GB1505095A Cited
US4274979A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-10-10 1987-04-11 1987-10-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-10-10 1991-04-11 1991-10-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-10-10 1995-04-11 1995-10-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag