Hydrogenation catalyst

Abstract

The present development relates to a catalyst composition for the selective hydrogenation of acetylene and to a method for preparing the catalyst. The catalyst comprises iridium, palladium and, optionally, at least one of the elements selected from the group consisting of silver, gold, copper, zinc and tin. In a preferred embodiment, the catalyst is prepared such that the palladium is located within the first 250 micrometers of the surface of the catalyst carrier. In contrast to the catalysts of the prior art, including for example, palladium / silver catalysts, the catalyst of the present invention exhibits high selectivity and an improved stability of the catalytic performance over an extended period of time.

Description

[0001] Cross-references to related applications [0002] This application claims priority to US Provisional Patent Application 60 / 645,431 (filed January 20, 2005), the disclosure of which is incorporated herein by reference in its entirety. technical field [0003] This development research relates to catalyst compositions and methods for preparing catalysts for use in hydrogenation processes. The catalyst comprises iridium, palladium and optionally at least one element selected from the group consisting of silver, gold, copper, zinc and tin. As described herein, the catalyst is useful in hydrogenation reactions such as the selective hydrogenation of acetylene. Background technique [0004] Processes for the preparation of unsaturated hydrocarbons generally involve the cracking of multiple types of hydrocarbons and thus often result in crude products containing hydrocarbon impurities having a greater degree of unsaturation than the desired product. These unsaturated hydroc...

AI Technical Summary

Problems solved by technology

However, it has been difficult to develop a long-term catalyst that can perform such selective hydrogenation

For example, it has been reported that palladium catalysts supported on γ-alumina can be used as effective selective hydrogenation catalysts, but their selectivity will drop rapidly within 100 hours of operation (for example, see British Patent 916056; J.Mol.Catal .A173(2001)185-221; Catal.Today 24(1997)181-197; J.Catal.158(1996)227-278; Appl.Catal.10(1984)369)