The solid-state rearrangement of the Wells-Dawson K6P2W18O62 center dot 10H(2)O to a stable Keggin-type heteropolyanion phase: A catalyst for the selective oxidation of isobutane to isobutene

被引：40

作者：

Comuzzi, C

Dolcetti, G

Trovarelli, A

Cavani, F

Trifiro, F

Llorca, J

Finke, RG

机构：

[1] DEPT IND CHEM & MAT,I-40136 BOLOGNA,ITALY

[2] UNIV BARCELONA,DEPT QUIM INORGAN,E-08028 BARCELONA,SPAIN

[3] COLORADO STATE UNIV,DEPT CHEM,FT COLLINS,CO 80523

来源：

CATALYSIS LETTERS | 1996年 / 36卷 / 1-2期

关键词：

Wells-Dawson heteropoly compounds; Keggin heteropoly compounds; phosphotungstates; isobutane oxydehydrogenation; isobutene synthesis;

D O I：

10.1007/BF00807208

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The thermal and structural stability of the Wells-Dawson-type heteropoly compound K6P2W18O62. 10H(2)O was examined by FT-IR spectroscopy, X-ray powder diffraction, thermogravimetric analysis and HRTEM. It was found that calcination at temperatures higher than 850 K led to the formation of a Keggin-type compound ''K3PW12O40'', containing small amounts of an additional phase originated from the high-temperature interaction between potassium phosphate (K3PO4, formed during the decomposition of the K6P2W18O62. 10H(2)O) and the Keggin-type compound itself. The Keggin-type product showed a higher activity in the selective oxidative dehydrogenation of isobutane to isobutene compared to both the Wells-Dawson precursor and to pure, authentic K3PW12O40. This higher activity can be tentatively attributed to the presence of an amorphous layer of unknown stoichiometry at the surface of the thermally rearranged Wells-Dawson compound.

引用

页码：75 / 79

页数：5

共 13 条

[1] MECHANISM OF THERMAL-DECOMPOSITION OF POTASSIUM AMMONIUM-SALTS OF THE 12-MOLYBDOPHOSPHORIC ACID AND EFFECT ON THE CATALYTIC PERFORMANCE IN THE ISOBUTYRIC ACID OXIDEHYDROGENATION [J].