Suitable catalysts for hydroisomerization of long-chain normal paraffins

Nowadays, isomerization of normal paraffins plays an important role in the petroleum industry. Isomerization reactions generally take place over bifunctional metal/acid catalysts. The suitable catalysts for hydroisomerization of long chain n-paraffins are reviewed in this paper. An ideal catalyst for this purpose should provide a high yield of isomerization and should have shape-selectivity to react only with n-paraffins. To achieve these characteristics, the catalyst should have suitable compositional and structural characteristics, mainly: proper balance between metal and acid sites, medium pore size, high dispersion of metal on surface of catalyst, mild acidity, and strength distribution of acid sites. Catalysts with mean pore size and low acidity that are loaded with noble metals, especially platinum, have very good performance in hydroisomerizations of long-chain normal paraffins. (c) 2005 Elsevier B.V. All rights reserved.