TY - JOUR
T1 - A novel titanosilicate with MWW structure
T2 - II. Catalytic properties in the selective oxidation of alkenes
AU - Wu, Peng
AU - Tatsumi, Takashi
AU - Komatsu, Takayuki
AU - Yashimay, Tatsuaki
PY - 2001
Y1 - 2001
N2 - The catalytic properties of Ti-MWW catalysts have been studied for the oxidation of alkenes using hydrogen peroxide or tert-butyl hydroperoxide (TBHP) as an oxidant. Ti-MWW shows superior activity independent of the nature of oxidant when compared to the other Ti-containing catalysts both of microporous TS-1 and TiMOR and of mesoporous Ti-MCM-41 in the oxidation of cyclohexene. Compared to large-pore Ti-Beta, Ti-MWW is less active than in the oxidation of cyclohexene using H2O2, but its shows comparable activity in the case of TBHP. Ti-MWW is very stable in both the structure and the states of Ti species in the actual cycle of reaction-regeneration. The framework B species remaining within the Ti-MWW catalysts seem to have little influence on the intrinsic activity of framework Ti species, but they act as Brønsted acid sites contributing to the hydrolysis of the oxide product to form glycols. The turnover number (TON) of Ti-MWW for the cyclohexene conversion decreases sharply with increasing Ti content, while the TON for the 1-hexene conversion shows volcanic behavior when related to the Ti content. It is clarified that the bulky reaction is catalyzed mainly by the Ti species within the supercages and the exterior pockets of the MWW structure, while in addition to these highly accessible Ti species, those within the channels of a 10-membered ring greatly contribute to the oxidation reactions not significantly sizedemanding.
AB - The catalytic properties of Ti-MWW catalysts have been studied for the oxidation of alkenes using hydrogen peroxide or tert-butyl hydroperoxide (TBHP) as an oxidant. Ti-MWW shows superior activity independent of the nature of oxidant when compared to the other Ti-containing catalysts both of microporous TS-1 and TiMOR and of mesoporous Ti-MCM-41 in the oxidation of cyclohexene. Compared to large-pore Ti-Beta, Ti-MWW is less active than in the oxidation of cyclohexene using H2O2, but its shows comparable activity in the case of TBHP. Ti-MWW is very stable in both the structure and the states of Ti species in the actual cycle of reaction-regeneration. The framework B species remaining within the Ti-MWW catalysts seem to have little influence on the intrinsic activity of framework Ti species, but they act as Brønsted acid sites contributing to the hydrolysis of the oxide product to form glycols. The turnover number (TON) of Ti-MWW for the cyclohexene conversion decreases sharply with increasing Ti content, while the TON for the 1-hexene conversion shows volcanic behavior when related to the Ti content. It is clarified that the bulky reaction is catalyzed mainly by the Ti species within the supercages and the exterior pockets of the MWW structure, while in addition to these highly accessible Ti species, those within the channels of a 10-membered ring greatly contribute to the oxidation reactions not significantly sizedemanding.
UR - https://www.scopus.com/pages/publications/57249109785
U2 - 10.1006/jcat.2001.3278
DO - 10.1006/jcat.2001.3278
M3 - 文章
AN - SCOPUS:57249109785
SN - 0021-9517
VL - 202
SP - 245
EP - 255
JO - Journal of Catalysis
JF - Journal of Catalysis
IS - 2
ER -