Synthesis method for acrylate with low polymerization inhibitor content

Abstract

The invention discloses a synthesis method for acrylate with a low polymerization inhibitor content. The method comprises the following steps: in the presence of at least one polymerization inhibitor,directly esterifying acrylic acid or methacrylic acid and corresponding alcohol serving as raw materials under the action of an acidic catalyst to synthesize corresponding acrylate or methacrylate, and introducing air into a reactor in the reaction process to take water generated by the reaction out of the reactor; after reacting for a period of time, filtering an esterification reaction solutionto remove the catalyst, and carrying out alkali washing and water washing to obtain a product acrylate or methacrylate, wherein the polymerization inhibitor is a compound polymerization inhibitor, and the compound polymerization inhibitor comprises a cobaloxime boron fluoride complex and a phenolic compound. By adopting the compound polymerization inhibitor, the usage amount of the polymerizationinhibitor can be reduced to 5-20 ppm, the oxygen content in the reactor is not required, the method is suitable for industrial production and application, the requirements of customers on acrylate products with low polymerization inhibitor content can be met, and a subsequent step of removing the polymerization inhibitor is omitted.

Description

technical field [0001] The invention relates to an acrylate synthesis method of a low-resistance polymerization agent, belonging to the field of chemical synthesis. Background technique [0002] (Meth)acrylic acid and its esters are one of the important organic raw materials, and the market prospect is very broad. Methyl methacrylate (MMA) is mainly used in the production of plexiglass, coatings, etc. Methacrolein and methacrylic acid are intermediate products in the process of synthesizing methyl methacrylate. These three substances contain carbon-carbon unsaturated double bonds and carbonyl groups. When the external conditions change, it is easy to polymerize. Factors such as light, temperature, and peroxides can all trigger their own polymerization, which is difficult to control. The generated polymers will block pipes, trays, and pump bodies, which will have a great impact on the stable operation of processes and devices. Therefore, inhibiting the polymerization of (...

AI Technical Summary

Problems solved by technology

Patent CN100402484C proposes a preparation process of (meth)acrylate, which uses a polymerization inhibitor including one of hydroquinone, p-hydroxyanisole, 2,6-di-tert-butyl-p-cresol, and saccharin Or more than one kind of mixture; but its addition needs to reach between 50-500ppm, the content of this polymerization inhibitor is relatively high, and it still cannot meet the requirements of some customers