1995 Fiscal Year Final Research Report Summary
Selective Infiltration of Fine Pores in Molecular Size by Use of CVI
Project/Area Number |
06805063
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
Structural/Functional materials
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Research Institution | Tohoku University |
Principal Investigator |
SHIGENO Yoshihito Graduate sohool of International Cultura Studies, Tohoku University, Technology Cooparation Division, Associate Professor, 国際文化研究科, 助教授 (70108570)
|
Project Period (FY) |
1994 – 1995
|
Keywords | Methane / Pyrolysis / CVI / Activated charcoal / Coke / Graphite / Pore / Micropore |
Research Abstract |
Chemical vapor infiltration is now being used to produce advanced materials for aerospace applications. It is also applicable to carbons to enhance the resisitance against oxidation. In the present study, methane pyrolysis was conducted for several kinds of carbons such as electrode-grade graphite electrode-grade carbon, coke and activated charcoal. The structural change of the fine pores : submicropore (diameter<1.5nm), micropore (d<2nm), mesopore (d<50nm), was investigated by use of nitrogen adsorption method. Those fine pores oreconsidered to have an important role for oxidation kinetics because in the case of inner burning, oxidation is considered mainly to occur in such fine pores due to their larger specific surface area comparing to those of macropores (d>50nm). The measured results indicates that the size of micropores decreases extremely for the infiltrated activated charcoal. Additionally, the opening rate of these pores are retarded to about 1/3 of the original sample during the oxidation. Therefore, it is concluded that the micro pores are attributed to the enhancement of oxidation resistance for activated charcoal as well as other carbons. The change of macropores measured by mercury porosimeter is compared with that of fine pores but is considered to have little effect on the enhancement of resistance.
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Research Products
(6 results)