• 作者： 楊錦瑤; 陳添進; 林強生; 劉瑞雄
• 作者服務機構： 國立清華大學化學研究所
• 中文摘要： 十二鎢酸含磷、鍺、硼、鐵及鋅化合物的表面積，穩定度及酸性皆與中心原子組成有關。這些化合物的甲醇、丙醇及二丁醇的脫水反應決定於中心原子。其觸媒反應機構以產生碳陽離子為中間產物為主要路徑。
• 英文摘要： A variety of Keggin-type 12-heterotungstic acids (方程式無法摘錄) containing different central ions(Xn+=pV，SilV, GeIV, gIII FeIII and ZnII) were prepared and their surface areas, acid strengths andthermal stabilities were characterized. Differentcentral ions in 12-heterotungstate compounds were foundto affect their thermal stabilities and acid strengths as well as the dehydration activities of 2-propanol and2-butanol. Over these heteropoly acids, 2-butanol yielded the three butenes, 1-butene, trans-2-butene andcis-2-butene with concentrations in thermal equilibrium, indicative of carbonium ions as common intermed-iates. On the silver and ammonium salts of 12-heterotungstates as catalysts, the dehydration selectivitiesand activities of methanol were found to be very sensitive to the central ions. These results were inter-preted as a consequence of variations in oxygen partial charges of 12-heterotungstate anion.
• 中文關鍵字： heteropolytungstates; catalysis; dehydrations; methanol
• 英文關鍵字： --