Process for the production of fibrous activated carbon
AssigneeToho Beslon Co., Ltd.
InventorsShigeru Ikegami, Minoru Hirai, Kazuo Izumi
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Abstract
A fibrous activated carbon having high adsorptivity and excellent mechanical properties is produced by preoxidizing an acrylonitrile-based fiber containing a specific amount of an iron compound at a specific initial heat-treatment temperature and then activating.
Claims17
A process for producing a fibrous activated carbon which comprises
- (1) spinning a dope of a polyacrylonitrile or a copolymer thereof comprising at least about 60 wt% acrylonitrile to thereby obtain an acrylonitrile-based fiber having a diameter of from 1.5 to 15 denier,
- (2) treating the acrylonitrile-based fiber with a solution of an iron compound to thereby obtain an acrylonitrile-based fiber containing the iron compound in the range satisfying the equation (1) ##EQU2## wherein X is the wt% content of comonomer in the acrylonitrile-based fiber and y is the wt% iron content,
- (3) preoxidizing the acrylonitrile-based fiber containing the iron compound at an initial heat-treatment temperature satisfying the equation (2)
- 28- 5X.ltoreq.Z.ltoreq.290-4X
- wherein X has the same meaning as in equation (1) and Z is the initial heat-treatment temperature (.degree.C.), the iron compound preventing substantial coalescence during preoxidizing, and
- (4) then gas activating the preoxidized acrylonitrile-based fiber.
A fibrous activated carbon containing an iron compound having a specific surface area of from about 300 to 2,000 m.sup.2 /g, a nitrogen content of from about 2 to 15 wt%, a fiber strength of from about 25 to 35 Kg/mm.sup.2 and a diameter of from about 3 to 30.mu., said fibrous activated carbon being produced by the process which comprises
- (1) spinning a dope of a polyacrylonitrile or a copolymer thereof comprising at least about 60 wt% acrylonitrile to thereby obtain an acrylonitrile-based fiber having a diameter of from 1.5 to 15 denier,
- (2) treating the acrylonitrile-based fiber with a solution of an iron compound to thereby obtain an acrylonitrile-based fiber containing the iron compound in the range satisfying the equation (1) ##EQU3## wherein X is the wt% content of comonomer in the acrylonitrile-based fiber and y is the wt% iron content,
- (3) preoxidizing the acrylonitrile-based fiber containing the iron compound at an initial heat-treatment temperature satisfying the equation (2)
- 28- 5X.ltoreq.Z.ltoreq.290-4X
- wherein X has the same meaning as in equation (1) and Z is the initial heat-treatment temperature (.degree.C.), the iron compound preventing substantial coalescence during preoxidizing, and
- (4) then gas activating the preoxidized acrylonitrile-based fiber.
Dependencies are inferred from the claim text.