2004 Fiscal Year Final Research Report Summary
Development of a novel catalyst for direct conversion of low valued natural gas containing carbon dioxide to petrochemical feedstock
Project/Area Number |
14350422
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
触媒・化学プロセス
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Research Institution | Tohoku University |
Principal Investigator |
OHTSUKA Yasuo Tohoku University, Institute of Multidisciplinary Research for Advanced Materials, Professor, 多元物質科学研究所, 教授 (20091663)
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Co-Investigator(Kenkyū-buntansha) |
TSUBOUCHI Naoto Tohoku University, Institute of Multidisciplinary Research for Advanced Materials, Research Associate, 多元物質科学研究所, 助手 (90333898)
KIKUCHI Takemitsu Tohoku University, Institute of Multidisciplinary Research for Advanced Materials, Research Associate, 多元物質科学研究所, 助手 (30169825)
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Project Period (FY) |
2002 – 2004
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Keywords | Natural gas / Carbon dioxide / Petrochemical feedstock / Binary oxide catalysts / Silica supports |
Research Abstract |
The present work focuses on developing a novel catalyst system for the purpose of directly converting low valued natural gas, which contains a large amount of CO_2, into petrochemical feedstock such as ethane and ethylene, in other words, for CH_4 coupling with CO_2 to produce C_2 hydrocarbons. In an unsupported binary oxide catalyst, which is composed of Mn oxide and alkaline earth metal oxide, C_2 selectivity increases in the order of Ca-Mn < Ba-Mn < Sr-Mn, and the value over the Sr-Mn catalyst reaches 80%, which is higher than those over Ca-Ce and Ca-Cr catalysts. The Ba-Mn and Sr-Mn provide almost no dependency of C_2 selectivity on partial pressure of CO_2 in feed gas, in contrast with the remarkable dependency observed with Ca based composite oxides. It is likely that this difference originates from chemical structures of catalytically active species and the mechanism of C_2 formation. When these oxide components are impregnated with a mesoporous molecular sieve silica (SBA-15) with high surface area (880m^2/g) and large pore volume (1.9cm^3/g), almost all of the oxide species can be held inside the mesopores with average pore diameter of 7.4nm, and C_2 selectivity is larger with Mn-based composites, whereas space time yield of C_2 hydrocarbons is higher with Ca-based composites. The use of conventional amorphous SiO_2 supports in place of the SBA-15 support shows that, although C_2 selectivity is larger with the latter, the yield of C_2 hydrocarbons is the highest with the Ca-Ce catalyst supported on the SiO_2 with the lowest surface area of 300m^2/g. To improve the selectivity over the supported Ca-Ce catalyst maybe the subject of future study.
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Research Products
(9 results)