Aldol condensation reaction solid base catalyst and application

Abstract

The invention relates to an aldol condensation reaction solid base catalyst and application. A composite oxide is used as a carrier which carries at least one alkali metal oxide in the catalyst, the composite oxide is a titanium oxide-aluminum oxide composite oxide or a zirconium oxide-aluminum oxide composite oxide, the mass percentage of Ti or Zr in the composite oxide is 0.1 to 30 percent, thealkali metal oxide is calcium oxide or magnesium oxide, and the mass percentage of the alkali metal in the catalyst is 0.1 to 40 percent; a fixed bed reactor is adopted, aliphatic aldehyde is contacted with the catalyst under a liquid phase condition at the temperature of between 60 and 260 DEG C to generate unsaturated aldehyde by reaction, and the catalyst is solid, so alkali aqueous solution is avoided, treatment and discharge of organic waste water are reduced, and the catalyst has excellent catalytic performance for the aldol condensation reaction; and particularly, the catalyst has goodstability, the reaction temperature is low compared with gaseous phase reaction, and the reaction result is superior to the reaction result under the gaseous phase reaction condition.

Description

Technical field: [0001] The invention relates to a solid base catalyst and an aldol condensation reaction, in particular to a solid base catalyst for an aldol condensation reaction and its application in an aldol condensation production process. Background technique: [0002] The aldol condensation reaction is an important carbon chain growth reaction in organic synthesis and an important method for the preparation of long-chain even-carbon alcohols. Aldehydes or ketones containing α-H undergo condensation reaction under the action of a basic catalyst to generate β-hydroxy aldehydes or ketones, which are dehydrated by heat to obtain α, β-unsaturated aldehydes or ketones. [0003] GB 1462328 describes the method of using a water-soluble base as a catalyst at 80°C to 140°C to generate high-carbon alcohols with double the carbon number from low-carbon aldehydes through condensation and hydrogenation. This method is also a production method commonly used in industry at present,...

AI Technical Summary

Problems solved by technology

Although the existing solid base catalyst has a certain initial activity, the activity declines rapidly

The gas phase aldol condensation reaction temperature is high, which easily leads to carbon deposition and deactivation of the catalyst

High-pressure liquid-phase condensation requires high reaction pressure and large investment in equipment