Catalyst for cracking methyl tert-butyl ether to prepare isobutylene and its prepn

Abstract

The present invention discloses one kind of catalyst for cracking methyl tert-butyl ether to prepare isobutylene and its preparation process. The catalyst includes carrier and supported bisulfate in the amount of 1.5-30 % carrier weight accounting in the bisulfate radical. It is prepared through soaking the carrier in water solution of bisulfate for 0.5-24 hr, filtering, drying at 100-130 deg.c for 1-8 hr and baking at 150-900 deg.c for 2-12 hr. The catalyst has high catalytic activity, high methyl tert-butyl ether converting rate at low temperature, high methanol and isobutylene selectivity and other advantages.

Description

technical field [0001] The invention relates to a catalyst for producing isobutene by cracking methyl tert-butyl ether and a preparation method thereof. Background technique [0002] Isobutene is an important organic chemical raw material. In recent decades, its social demand has been growing rapidly. It can not only be used to make gasoline and lubricating oil additives, but also can be used as an important auxiliary and raw material for other chemical products. For example, low-purity isobutylene is a raw material for antioxidants, pesticides, paints, water stabilizers and other fine chemicals. High-purity isobutylene is a monomer raw material for polyisobutylene, butyl rubber, isoprene rubber, polybutene resin, methyl methacrylate, etc. According to the information released by the China Petroleum and Chemical Industry Association, the domestic polyisobutylene consumption has continued to rise in recent years, reaching 45,000 t / a in 2005, and it is expected to exceed 50...

AI Technical Summary

Problems solved by technology

The raw materials used in the niobic acid and tantalic acid component catalysts are expensive, which greatly increases the cost of the catalyst

Due to the poor high temperature resistance of cationic resin catalysts, it is impossible to achieve a balance between catalyst life and catalyst activity, and the modification method greatly increases the cost of the catalyst

One of the main disadvantages of silicon-aluminum compound catalysts is that the catalytic performance is significantly affected by the purity of silicon oxide raw materials, and the selectivity of methanol still needs to be improved. Therefore, it is often necessary to introduce a small amount of water into the reaction system to improve methanol. selectivity

The catalytic activity of the basic component catalyst is obviously low, which is not conducive to industrial production and application

And some catalysts of other types also exist or the cost of the catalyst is too high, or the product selectivity is not good, or it is impossible to achieve a balance between catalytic activity and product selectivity.