Method for preparing 3-hydroxypropionaldehyde by acrylaldehyde hydration

Abstract

The invention refers to a method of mading 3-hydroxy propionaldehyde from acraldehyde through hydration. We mix the acraldehyde with the water to get the acraldehyde solution. The thickness of the acraldehyde is between 8wt% and 25wt%. The acraldehyde solution passes through the static bde of catalys to hydrate at the reaction temperature of between 40deg.C and 80deg.C and at the speed in the liquid of 3hr-1 and 10 hr-1. The hydration reaction happens in the condition of carbon dioxide gas, with the branch pressure of the carbon dioxide gas between 0.01MPa and 1.5MPa, and the rest is inert gases. That the hydration reaction happens in the condition of carbon dioxide gas can effectively prevent the self polymerization of the acraldehyde. Compared with the now-existing technoloty of adding organic material as the inhibitor, the whole technology is more simple and easier to operate. And the inhibitor chosen don't affect the production of the hydrating outcome.

Description

technical field [0001] The invention relates to a method for preparing 3-hydroxypropanal by hydration of acrolein, in particular to a method for preparing 3-hydroxypropanal by passing an aqueous solution of acrolein through a fixed-bed catalyst bed where the catalyst is a weakly acidic chelating cation exchange resin. Background technique [0002] The hydration of acrolein to generate 3-hydroxypropionaldehyde, and then hydrogenation to produce 1,3-propanediol is one of the successful industrial production routes at present, in which high-purity fiber-grade 1,3-propanediol is polytrimethylene terephthalate The main monomer of fiber (PTT), the purity requirement is very high. At present, the acrolein hydration reaction basically adopts a fixed-bed catalyst, such as the acidic cation exchange resin catalyst containing phosphoric acid groups proposed in U.S. Patent No. 5,015,789, the chelating cationic resin catalyst or heteropolyacid proposed in U.S. Patent No. 5,171,898 or mo...

AI Technical Summary

Problems solved by technology

It is said that this can effectively prevent the self-polymerization of acrolein, but there is a common defect in these methods, that is, the added organic matter with polymerization inhibition must be separated from the hydration reaction product, which increases the complexity of the process

And usually these organic inhibitors are difficult to separate from the hydration reaction product, and the residual organic inhibitors will affect the purity of the final product 1,3-propanediol

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