Method for refining and purifying propylene oxide

Abstract

The invention provides a method for refining and purifying propylene oxide. The method is characterized by comprising the steps that an epoxidation reaction product enters a propylene separating column to be separated into column top materials and column bottom materials, wherein the column top materials contain propylene, propylene oxide and methanol and contain or do not contain propane and water, and the column bottom materials contain methanol, water, hydrogen peroxide and high-boiling-point byproducts; column top materials from the propylene separating column enter a propylene stripping column, and the column top gases contain propylene and little propylene oxide and contain or do not contain propane and circulate to a reaction system after compression; and column bottom materials contain methanol, propylene oxide and few aldehyde ketone impurities and contain or do not contain water, enter a reactor filled with alkaline ion exchange resins to react to remove methyl formate and aldehyde out of the column bottom materials and are further refined through rectification to obtain the high-purity propylene oxide product. The invention also provides a separation method for preparing propylene oxide and the product through direct epoxidation. The method provided by the invention has the beneficial effects that the low temperature and low pressure process is adopted, thus increasing the yield of propylene oxide, reducing the losses of propylene oxide and reducing the operating costs of the devices.

Description

technical field [0001] The present invention relates to a kind of refining method of propylene oxide, more specifically, relate to a kind of method of refining propylene oxide in the reaction product of preparing propylene oxide by reacting hydrogen peroxide and propylene. Background technique [0002] Propylene oxide (Propylene Oxide) is an important raw material for organic synthesis, and is the third largest propylene derivative besides polypropylene and acrylonitrile. It is mainly used in the production of polyether, propylene glycol, propylene glycol ether, etc. It is also an important raw material for non-ionic surfactants, oil field demulsifiers, and pesticide emulsifiers. Propylene oxide derivatives are also widely used in industries such as food, tobacco, pesticides and cosmetics. Nearly 100 kinds of downstream products have been produced, which are important raw materials for fine chemical products. [0003] Propylene oxide production processes mainly include chl...

AI Technical Summary

Problems solved by technology

The propylene oxide product through this refining process still contains trace impurities such as acetaldehyde, methyl formate and acetone, and needs to be further refined to obtain refined propylene oxide, which makes the process of refining propylene oxide longer and consumes less energy. high

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