A Study on Acid-catalysis by Silver-exchanged Zeolites

银交换沸石酸催化研究

• 批准号: 62470072
• 负责人: ONO Yoshio
• 金额: $ 3.84万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-62470072/
• 关键词: Ag-exchanged Zeolite; Hydrogen effect; Acid catalysis; 銀交換ゼオライト

The rate of solid-acid-catalyzed reactions are greatly enhanced by hydrogen present in the system. Thus, the catalytic activities of prereduced silver-exchanged Y-zeolites (AgY) for the disproportionation of ethylbenzene and the isomerization of o-xylene are several times higher than those of hydrogen Y- zeolites, the only in the presence of gaseous hydrogen. The enhancing effect of hydrogen was also observed for isomerization 1-butene and dehydration of alcohols over AgY. The similar enhancing effects of hydrogen on the catalytic activities are observed also in the conversion of methanol into hydrocarbons and the isomerization of 1-butene over prereduced form of silver dodecatungstophosphate.A dramatic enhancement was observed in the methanol .conversion over the combination catalysts of transition metal (Pd or Pt)-heteropoly acid supported on silica.Though the catalytic systems are versatile, there are some common features: The enhancement occurs only for acid-catalyzed reactions. The enhancing effect is reversible. The adsorption amount of hydrogen on the catalysts is small. These findings indicate that there is interconversion of molecular hydrogen in the gas phase and protons on the surface, and the activities of the protons induced from gaseous hydrogen are far higher than those of the protons from OH groups in zeolites or from parent heteropoly acids.

系统中存在的氢气大大提高了固体酸催化反应的速率。因此，预还原银交换Y-沸石（AgY）对乙苯歧化和邻二甲苯异构化的催化活性比氢Y-沸石高数倍，这是唯一在气态氢存在下的催化活性。还观察到氢气对 1-丁烯异构化和醇在 AgY 上脱水的增强作用。在甲醇转化为碳氢化合物和 1-丁烯在预还原形式的十二钨磷酸银上的异构化中也观察到氢对催化活性的类似增强作用。在过渡组合催化剂上观察到甲醇转化率显着增强。二氧化硅负载的金属（Pd 或 Pt）-杂多酸。虽然催化系统用途广泛，但有一些共同特征： 增强仅发生在酸催化反应中。增强作用是可逆的。催化剂上氢气的吸附量较小。这些结果表明，气相氢分子与表面质子之间存在相互转化，并且气态氢诱导的质子活性远高于沸石中OH基团或母体杂多酸的质子活性。

项目成果

Toshihide Baba,Yoshio Ono: "Enhancing Effect of Hydrogen on the Catalytic Activity Trisilver Dodecatungstophosphate for the Isomerization of 1-Butene" Appl.Ctal.,. 55. 301-314 (1989)

Toshihide Baba、Yoshio Ono：“氢对十二钨磷酸三银催化 1-丁烯异构化活性的增强作用”Appl.Ctal.,。

Yoshio Ono, Toshihide Baba, Kunihiko Kanae, Seong Gyu Seo: "Hydrogen-Induced Acid Catalysis over Heterogeneous Catalysts," Nippon Kagaku Kaishi, 985-994, 1988.

Yoshio Ono、Toshihide Baba、Kunihiko Kanae、Seong Gyu Seo：“多相催化剂上的氢诱导酸催化”，Nippon Kagaku Kaishi，985-994，1988。

T.Baba;S-G.Seo;Y.Ono: Stud.Surface.Sci.37. 443-450 (1987)

T.Baba；S-G.Seo；Y.Ono：Stud.Surface.Sci.37。

Toshihide Baba, Yoshio Ono: "Enhancing Effect of Hydrogen on the Catalytic Activity of Trisilver Dodecatungstophosphate for the Isomerization of 1-Butene" Appl. Catal., 55, 301-314, 1989.

Toshihide Baba、Yoshio Ono：“氢对十二钨磷酸三银催化 1-丁烯异构化活性的增强作用”

Toshihide Baba, Yoshio Ono: "Hydrogen Induced Catalysis by Silver-Exchanged Zeolites:Transformation of Ethylbenzene over AgY Zeolite" Zeolites. 7. 292-294 (1987)

Toshihide Baba、Yoshio Ono：“银交换沸石的氢诱导催化：乙苯在 AgY 沸石上的转化”沸石。