Fluidization catalyst for producing dimethyl ether through methanol dehydration

Abstract

The invention provides a fluidized catalyst which can generate dimethyl enther by methanol dehydration reaction. The fluidized catalyst is one or more compounds out of alumina, Si-Al oxide, Si-Al molecular sieve, Si-P-Al molecular sieve, wherein, the alumina is active alumina, pseudo-boehmite and artificial boehmite; the Si-Al oxide can adopt kaolin and clay; the Si-Al molecular sieve can adopt ZSM-5, ZSM-11, Y, mordenite, Beta-zeolite, MCM-22, MCM-41, MCM-56, and MCM-49; and the Si-P-Al molecular sieve can adopt SAPO-5, SAPO-11, SAPO17, SAPO-18, SAPO-34, SAPO-44 and SAPO-56. The selectivity of the dimethyl enther is 100 percent on the fluidized reactor under the conditions of reaction temperature of 100-400DEG C, reaction pressure of 0.1-4.0MPa, and empty speed of feeding weight of 0.1-10h<-1>.

Description

technical field [0001] The invention relates to a fluidized catalyst for dehydrating methanol to produce dimethyl ether. Background technique [0002] Dimethyl ether is a widely used chemical product and fuel substitute. DME was first produced by methanol dehydration, and the reaction was carried out in the liquid phase, using concentrated sulfuric acid as a catalyst. The main disadvantages are serious corrosion of equipment, harsh operating conditions, and serious environmental pollution. At present, the process of producing dimethyl ether by dehydration of methanol with solid acid catalyst is the main method and the future development trend in industry. [0003] U.S. Patent No. 6,740,783 discloses a molecular sieve catalyst for producing dimethyl ether from methanol. The molecular sieve catalyst exchanged with metal or amine is used, and methanol vapor is dehydrated in a fixed-bed reactor. [0004] Chinese patent CN 1036199A discloses a method for producing dimethyl eth...

AI Technical Summary

Problems solved by technology

[0007] In Chinese patent ZL 94222811.1, a gas-solid phase multi-terminal chilling method is proposed, which is to control the temperature of the catalyst bed by injecting cold air into the catalyst bed of the reactor. Since the methanol dehydration reactor is a strong exothermic reaction, the cold air Insufficient to reduce catalyst bed temperature, therefore, under reaction temperature conditions, it is difficult to control bed temperature by this method

[0011] In the above inventions, the use of liquid acids such as sulfuric acid as catalysts will cause equipment corrosion and environmental pollution problems, and it is difficult to obtain high-purity dimethyl ether products by directly synthesizing dimethyl ether from synthesis gas

Using a modified alumina catalyst to produce dimethyl ether from methanol gas phase dehydration can obtain dimethyl ether with high purity, but the reaction temperature is relatively high, generally 200-380 ° C, which is easy to generate hydrocarbon by-products, which is not good for the stability of the catalyst.