A method for synthesizing n-butenes from carbon four olefins by skeleton normalization

Abstract

The application discloses a method for normalizing mixed C4 olefins containing isobutene. The method comprises the following steps: 1) adding 1-20wt% of tert-butyl alcohol into mixed C4 hydrocarbon; 2) feeding the obtained mixed raw material into a normalizing unit to generate normal butene under the conditions of 280-400 DEG C and normal pressure. The normalizing catalyst comprises the following components: a) 10-20wt% of a binder; and b) 80-90wt% of ZSM-35 molecular sieve. In the method, the tert-butyl alcohol can be hydrolyzed into isobutene and water in the reaction process, the isobutene can be used as the C4 raw material, the water can react with the C4 olefins to generate the intermediate product C4 alcohol, the C4 alcohol can be dehydrated to generate normal butene, and in addition, the water can play a role in inhibiting the hydrogenation of the raw material or the intermediate in the reaction system, thereby reducing the generation probability of alkanes and improving the selectivity of normal butene. The method can efficiently and stably convert the C4 olefins in the raw material into normal butene-rich product, and provides an effective way for synthesizing normal butene.

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