Isomerization Catalyst

There are mainly the following categories: ①Bai Friedel-Craft du special catalyst, commonly used are aluminum trichloride-hydrogen chloride, boron fluoride zhi-hydrogen fluoride and so on. This kind of dao catalyst has high activity and low reaction temperature, and is used for liquid phase isomerization, such as isomerization of n-butane to isobutane, isomerization of xylene, etc. ②Precious metal catalysts with solid acid as carrier, such as platinum-alumina, platinum-molecular sieve, palladium-alumina, etc. This type of catalyst is a dual-function catalyst, in which the metal component plays the role of hydrogenation and dehydrogenation, and the solid acid plays the role of isomerization. When this type of catalyst is used, the reaction needs to be carried out in the presence of hydrogen, so it is also called a hydroisomerization catalyst for gas phase isomerization. The isomerization of alkanes, alkenes, aromatics, and cycloalkanes can also be used. Especially the isomerization of ethylbenzene into xylene and cycloalkane is only effective with this kind of catalyst. Its advantages are less coking and long service life. ③Non-precious metal catalysts supported by solid acids, such as nickel-molecular sieves, generally require hydrogen to be used for gas phase isomerization, but cannot isomerize ethylbenzene to xylene. ④ZSM-5 molecular sieve catalyst is mainly used for the gas or liquid phase isomerization of xylene.