Hits:

Indexed by:期刊论文

Date of Publication:2002-01-01

Journal:Chinese Journal of Catalysis

Included Journals:Scopus、PKU、ISTIC

Volume:23

Issue:6

Page Number:496-497

ISSN No.:18722067

Abstract:The structure and surface acidity of TS-1 were adjusted by heat treatment, to increase its selectivity for propylene oxide (PO) in epoxidation of propylene with H2O2. The TS- 1 samples, treated at different temperatures in the presence of different media were characterized to determine the changes of their framework structure, surface acid sites, and total amount of acid. Using propylene epoxidation as a probe, the influence of the treatment conditions on their selectivity for PO was investigated. with the treatment temperature increasing, the Bronsted acid sites and the total amount of acid decreased. The selectivity for PO, especially over TS-1 sample treated at 750  C in the presence of vapor, increased from 29 to 56% while the catalytic activity remained constant. The decrease in surface acidity of TS-1 was due to the removal of framework aluminum when TS-1 was treated at high temperature; while the decrease in surface acidity of TS-1 led to the selectivity for PO increase.