Method for preparing low-carbon olefin from methanol

Abstract

The invention relates to a method for preparing low-carbon olefin from methanol. In the method, the reaction of preparing low-carbon olefin from methanol and the reaction of preparing ethylene and propylene from etherified C4 and C5 through cracking are carried out in the same reactor. The reactor is a rapid fluidized bed reactor with a lifting pipe. The method comprises the following steps: vaporizing and preheating a raw material methanol, then feeding into a rapid fluidized bed reactor, and reacting under the action of a modified ZSM-5 molecular sieve catalyst to generate a product gas containing low-carbon olefin and obtain a spent catalyst at the same time; separating the product gas to obtain ethylene, propylene, C4, C5 and aromatic hydrocarbon oil, enabling the C4 to react in an etherification device to generate MTBE, returning the C5 and etherified C4 to the reactor through a riser, and cracking to generate ethylene and propylene; the spent catalyst is divided into two streams, one stream enters a regenerator to be burnt and regenerated to obtain a regenerated catalyst, and the other stream serves as a circulating spent catalyst, is mixed with the regenerated catalyst from the regenerator and then returns to the reactor through a lifting pipe.

Description

technical field [0001] The invention relates to a method for preparing light olefins by using methanol as a raw material. Specifically, a fast fluidized bed reactor and a supporting regenerator are used to make the reaction of methanol to olefins and the cracking reaction of C4C5 after ether be carried out in the same reactor, and share a reaction regeneration system and a set of reaction Product separation system. Background technique [0002] Ethylene and propylene are important basic chemical products, mainly produced by naphtha cracking. With the development of economy and society, the global demand for ethylene and propylene continues to grow rapidly, while at the same time non-renewable petroleum resources are increasingly scarce. The technology of synthesizing low-carbon olefins from coal and natural gas via methanol has sprung up, providing a non-petroleum route to prepare low-carbon olefins, giving full play to the advantages of my country's coal resources and mak...

AI Technical Summary

Problems solved by technology

The method requires multiple reactors and no yield data are given

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