Method for converting methanol into propylene

Abstract

The invention discloses a method for converting methanol into propylene, which comprises the following steps of: introducing methanol into a methanol reaction zone to perform reaction so as to obtain a mixture of the methanol, dimethyl ether and water; dividing the mixture into a plurality of reactant streams; feeding the first reactant stream to a first reaction zone to perform reaction to obtain a product stream, mixing the product stream and any one of the other reactant streams, feeding the mixture to the first reaction zone to perform reaction until the product stream is mixed with the last reactant stream and feeding the mixture to the first reaction zone to perform reaction so as to obtain a primary reaction product stream; separating the primary reaction product stream to obtain the propylene, propane, C1 to C2 hydrocarbon, C4 hydrocarbon, C5 to C6 hydrocarbon and hydrocarbons with more than seven carbon atoms; circulating the C1 to C2 hydrocarbon and the C4 hydrocarbon to the first reaction zone to perform reaction continuously; feeding the C5 to C6 hydrocarbon and part of the hydrocarbons with more than seven carbon atoms to the second reaction zone to perform reaction so as to obtain a secondary reaction product stream; and separating the secondary reaction product stream to obtain the propylene. The method is suitable for the reactions with high heat discharge and temperature sensitivity such as the reaction for preparing the propylene from the methanol and has the advantages of high target selectivity, continuous and stable reaction and high efficiency.

Description

technical field

[0001] The invention relates to a method for preparing propylene, in particular to a method for converting methanol into propylene. Background technique

[0002] Propylene is a basic chemical raw material necessary for the modern chemical industry. With the continuous development of the industrial economy, the demand will continue to grow in the future. The traditional industrial production of propylene basically uses petroleum-based substances as raw materials, such as steam cracking of petroleum, etc. As a non-renewable resource, oil is facing a crisis of being exhausted in the long run after years of excessive exploitation and consumption. In the short term, the price fluctuates violently due to factors such as geography, economy, and politics. A method that can replace petroleum as a raw material to produce propylene has been sought.

[0003] Methanol to propylene technology is a non-petroleum resource propylene production process with great application ...

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