Reactivity of Hydrosilanes with the CrII/SiO2 Phillips Catalyst: Observation of Intermediates and Properties of the Modified CrII Sites

被引：3

作者：

Barzan, Caterina ^{[1
,2
]}

Bordiga, Silvia ^{[1
,2
]}

Quadrelli, Elsje Alessandra ^{[3
]}

Groppo, Elena ^{[1
,2
]}

机构：

[1] Univ Turin, Dept Chem, NIS Ctr, Via G Quarello 15A, I-10135 Turin, Italy

[2] Univ Turin, INSTM, Via G Quarello 15A, I-10135 Turin, Italy

[3] Univ Lyon, Univ Lyon 1, CPE Lyon, CNRS,UMR 5265 C2P2, Bat 308F,43 B 11 Novembre 1918, F-69616 Villeurbanne, France

来源：

TOPICS IN CATALYSIS | 2016年 / 59卷 / 19-20期

关键词：

Phillips catalyst; Hydrosilanes; Tandem catalysis; Chromium hydride; FT-IR spectroscopy; SIGMA-BOND METATHESIS; LOW-DENSITY POLYETHYLENE; ETHYLENE POLYMERIZATION; BRANCHED POLYETHYLENE; TANDEM CATALYSIS; CR(II) SITES; CHROMIUM; SYSTEM; SPECTROSCOPY; MECHANISM;

D O I：

10.1007/s11244-016-0694-8

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

The reaction of hydrosilanes (both silane and triethylsilane) with Cr-II/SiO2 catalyst has been investigated in detail by analysis of the gaseous by-products, temperature-and pressure-resolved FT-IR spectroscopy and deuterium exchanges. We found that the reaction proceeds via two steps, passing through intermediates characterized by elongated Si-H bonds and transient Cr-hydride species leading to the release of H-2 in the gas phase. These experimental evidence allowed us to advance an hypothesis of the reaction mechanism, which validates our previous proposal for the structure of the modified chromium sites. Furthermore, based on the intermediates of the reaction mechanism, we have also tested the ability of the modified "homogeneous-like'' Cr-II sites toward H-2 (D-2) activation, demonstrating that, contrarily to the unmodified Cr-II species, such reactivity is present.

引用

页码：1732 / 1739

页数：8

共 43 条

[1] Direct synthesis of linear low-density polyethylene of ethylene/1-hexene from ethylene with a tandem catalytic system in a single reactor [J].