Structure and Surface Chemistry of Two-Dimensional Phosphate Catalysts
| Project/Area Number |
62550597
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
工業物理化学
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| Research Institution | Sophia University, (Jouchi Daigaku) |
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Principal Investigator |
SEGAWA Kohichi Department of Chemistry, Faculty of Sci. & Tech., Sophia University Assistant Pr, 理工学部, 助教授 (60053675)
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| Project Period (FY) |
1987 – 1988
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| Project Status |
Completed (Fiscal Year 1988)
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| Budget Amount *help |
¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1988: ¥600,000 (Direct Cost: ¥600,000)
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| Keywords | Layered compound / zirconium phosphate / solid acid catalyst / 固体酸触媒 / ^<31>P-MASNMR / 固体酸触媒反応 / ^<31>PーMASNMR / アルケンの異性化 / メチルアミン合成 |
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| Research Abstract |
Zirconium phoshate are crystallized during the removal of hybration water in the zirconium phosphate gel with phosphoric acid slution under reduced pressure. Several forms of crystallites are obtained by this procedure, depending on the temperature and process time, for a given concenttration of phosphoric acid. Synthetic ZrP_2O_2 and epsilon-Zr(HPO_4)_2 catalysts, which were evacuated at ca. 800 K, showed higher catalytic activities for catalytic isomerization of alkenes than other forms of zirconium phosphates or other conventional solid acid catalysts. In order to elucidate those higher catalytic activities, ^<31>P magic angle spinning nmr (^<31>P-MASNMR) has been employed to study zirconium phosphates after evacuation at different temperatures.
The ^<31>P chemical shifts move towards higher magnetic fields as the layer separations became amaller. The catalysts which showed higher activities showed higher chemical shifts at around -38 ppm from H_3PO_4. These results suggest that phosphate froups remaining after evacuation at around 800 K may enhance the protonic characteristics, since the accumulation of electrons moves from the phosphate groups on the surface to phosphorus atoms which are located between Zr atom planes.
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Report
(3 results)
Research Products
(10 results)
