Solid phosphoric acid catalyst and methods of olefin dimerization reaction with the same

Abstract

A solid phosphoric acid catalyst which has high activity and attains high dimer selectivity in olefin dimerization reactions; and efficient methods of olefin dimerization reaction. The solid phosphoric acid catalyst comprises a support and phosphoric acid deposited thereon. When the solid phosphoric acid catalyst is heated at 250 DEG C for 20 minutes, the heating loss of water is 50 mass% or larger based on diphosphorus pentaoxide (P2O5) derived from the phosphoric acid. One of the methods of olefin dimerization reaction comprises bringing an olefin-containing feed material containing water in an amount of 10-1,000 mass ppm into contact with the catalyst to initiate the reaction. Another method of olefin dimerization reaction comprises successively conducting the following steps: a step (1) in which a hydrocarbon containing water in an amount of 10-1,000 mass ppm and containing substantially no olefin is brought into contact with the catalyst; a step (2) in which the pressure and temperature are regulated to conditions suitable for the initiation of olefin dimerization; and a step (3) in which the hydrocarbon is displaced with an olefin-containing feed material containing water in an amount of 10-1,000 mass ppm to bring the olefin into contact with the solid phosphoric acid catalyst and thereby initiate the reaction. Still another method is the olefin dimerization reaction method described above wherein the temperature in the reaction initiation conditions is higher by 5-50 DEG C than the reaction temperature in olefin dimerization in a stationary state after the step (3).

Description

technical field [0001] The invention relates to a solid phosphoric acid catalyst formed by supporting phosphoric acid on a carrier and a method for selective dimerization of olefins using it. Background technique [0002] Oligomers of olefins are used in various applications, especially dimers of low-molecular-weight olefins (such as propylene, n-butene, isobutene, and pentenes) are important as high-octane base materials for gasoline or chemical intermediate raw materials of. Oligomerization including olefin dimerization is performed using an acid catalyst, and numerous studies have been conducted so far. As the acid catalyst, solid acids such as sulfuric acid, hydrogen fluoride, phosphoric acid, aluminum chloride, boron fluoride, amorphous or crystalline aluminum silicate, clay, ion exchange resins, mixed oxides, carrier-supported acids can be cited as common examples, and Various studies have been conducted on an inexpensive solid phosphoric acid catalyst capable of a s...

AI Technical Summary

Problems solved by technology

[0005] However, the oligomerization of olefins using the above-mentioned existing solid phosphoric acid catalysts does not take the dimerization of olefins as the main purpose, and the existing solid phosphoric acid catalysts cannot avoid the generation of by-products such as high polymers of olefins, so it is difficult to choose Obtain dimers of alkenes

In addition, the existing solid phosphoric acid catalyst must be in the H 2 O / P 2 o 5 When it is supplied to the reaction in a small state, it is necessary to strictly control the moisture content during the preparation and storage of the catalyst so that the moisture content is below a certain level (the remaining moisture is reduced), and the drying process of the catalyst must be carried out before the reaction. all kinds of trouble