This article reviews the surface science of the heterogeneous olefin polymerization catalysts. The specific focus is on how to prepare and characterize stereochemically specific heterogeneous model catalysts for the Ziegler-Natta polymerization. Under clean, ultra-high vacuum conditions, low-energy electron irradiation during the chemical vapor deposition of model Ziegler-Natta catalysts can be...

The lack of stability is a challenge for most heterogeneous catalysts. During operations, the agglomeration of particles may block the active sites of the catalyst, which is believed to contribute to its instability. Recently, titanium oxide (TiO2) was introduced as an alternative support material for heterogeneous catalyst due to the effect of its high surface area stabilizing the catalysts in...

The epoxidation reaction using heterogeneous solid catalysts with H2O2 as oxidants are environmentally friendly routes to produce extensively useful epoxides which are traditionally obtained from capital-intensive or environmentally polluted processes. In this paper, various types of solid catalysts for the epoxidation of olefins with H2O2 as oxidants are reviewed. The efficient catalysts repor...

Heterogeneous catalysts are receiving more importance for the transesterification of triglycerides present in any oils or fats to produce biodiesel. They are reusable, environmentally benign, could give high quality of products, and more effective than acid catalysts and enzymes for biodiesel production. Recently, heterogeneous catalysts derived from both waste industrial and biological resourc...

An efficient method for the synthesis of heterogeneous gold catalysts has been developed. These catalysts were easily assembled from readily available silica materials and gold complexes. The heterogeneous catalysts exhibited superior reactivity in various reactions where protodeauration is the rate-limiting step. Dramatic enhancement in regio- and enantioselectivity was observed when compared ...

eethylene polymerization catalysts became available in an enormous variety. the challenge in this research is to find catalysts that are able to connect ethylene molecules in such a way that not only linear chains are produced but variations like branched materials that possess very interesting mechanical properties like linear low density polyethylene (lldpe). in this contribution, three diffe...

A combination of the advantages of homogeneous and heterogeneous catalysis could enable the development of sustainable catalysts with novel reactivity and selectivity. Although heterogeneous catalysts are often recycled more easily than their homogeneous counterparts, they can be difficult to apply in traditional organic reactions and modification of their properties towards a desired reactivit...

Homogeneous catalysts usually show higher catalytic activities than heterogeneous catalysts because of their high dispersion of catalytically active sites. We demonstrate here that heterogeneous catalysts of ionic liquids functionalized on superhydrophobic mesoporous polymers exhibit much higher activities in transesterification to form biodiesel than homogeneous catalysts of the ionic liquids ...