Preparation method of high-acidity fluorination resin catalyst used for alkylating of isobutane and butene

Abstract

The invention relates to a preparation method of a high-acidity fluorination resin catalyst used for alkylating of isobutane and butene, which includes conducting suspension polymerization on two monomers including styrene and diethylbenzene olefinic benzene to prepare body resin and then conducting sulfonation functionalization and fluorination process to strengthen acidity to obtain a catalyst with a resin framework provided with a sulfoacid base group and a fluorine substituent group. The catalyst overcomes the shortcoming that the common acidity exchange resin catalyst is low in acidity, is high in acidity, is similar in number with the existing industrial liquid acid catalyst and meets the requirements for alkylate reaction of isobutane and butene to combine alkylate oil. By means of the fixed bed reaction process method matched with the fluorination resin solid acid catalyst, the butene conversion rate can reach over 99% in continuous reaction with the reaction temperature smaller than 80 DEG C, the alkylate oil yield is over 190wt% counted by butene, and trimethylpentane MTP content in C8 hydrocarbon is over 75%. Compared with the prior art, the high-acidity fluorination resin solid acid catalyst achieves the actual effects of being simple in process flow, high in reaction activity, high in alkylate oil yield, free of environment pollution and stable in operation.

Description

technical field [0001] The invention relates to the catalyst technology of alkylation reaction in petrochemical industry, in particular to a preparation method of a strongly acidic fluorinated resin catalyst used for the alkylation of isobutane and butene. Background technique [0002] The development of green and environmental protection in today's society puts forward higher requirements on the content limits of sulfur, aromatics and additives in gasoline. At present, the octane number of gasoline refined from petroleum mainly comes from isoparaffins, olefins, aromatics, methyl tert-butyl ether (MTBE), alcohols and other antiknock additives that make up gasoline. However, the combustion of olefins and aromatics will cause harmful substances in the exhaust gas; the leakage of MTBE will pollute groundwater resources, and because its concentration at the ppm level will make drinking water foul, it has been banned in some developed countries; Alcohols (such as ethanol) are li...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent CN1277893 reports a modified zeolite beta catalyst used in the alkylation reaction of isobutane / butene to produce high-octane gasoline, using zeolite beta as the matrix, and leaching with metal salts after conventional dealumination, and then Promoted with sulfate, or loaded with titanium chloride, the modified zeolite beta is roasted; the catalyst prepared by this method can significantly improve the activity and selectivity of the alkylation reaction; but the catalyst still exists The reaction activity decreases rapidly, and the content of trimethylpentane isomers in the product alkylate is low

This is because the zeolite solid acid catalyst has less acidity than the liquid acid catalyst, and the opening size of the zeolite pores is small, which is easily blocked by product and by-product molecules and cannot perform mass transfer and diffusion, resulting in unsatisfactory reactivity and stability. It cannot be used as a catalyst for alkylation reaction to replace liquid acid for industrial application

[0005] Chinese patent CN1125640 proposes a solid heteropolyacid salt catalyst for the alkylation of isobutane and butene. Alkali metals (Cs, Cs, K) and ammonium (NH + 4 , N (C 2 h 5 ) + 4 ) salt is used as a catalyst to catalyze the alkylation reaction of isobutane and butene, the alkane component in the alkylate oil accounts for more than 95%, the optimal oil yield based on the weight of olefin is greater than 150%, and it has no sulfuric acid and the strong corrosiveness and toxicity of hydrofluoric acid; but the catalyst has the problem of poor long-term use stability, which restricts its industrial application

[0008] From the above analysis of the existing alkylation oil synthesis technology, it can be seen that the problem that currently restricts the industrial application of solid acid catalysts to replace liquid acids is that their reaction stability is poor, and they cannot be used as fixed bed catalysts for continuous alkylation reactions. application

On the other hand, the sulfonated styrene resin catalyst has a large pore structure and acid content, its reaction conditions are relatively mild, and its service life is much longer than that of zeolite molecular sieves; Therefore, it cannot be directly used in the alkylation reaction of isobutane and butene