Method for recycling heavy components of methyl acrylate

Abstract

The invention provides a method for recycling heavy components of methyl acrylate. The method comprises the following steps: 1) carrying out thermal cracking in a thermal cracking reactor by using byproduct heavy components of methyl acrylate, methanol and water as reaction raw materials to obtain gas-phase light components and heavy components from the thermal cracking reactor; 2) feeding the heavy components obtained in the thermal cracking reactor into a catalytic cracking reactor, and carrying out catalytic cracking in the presence of a catalyst and a polymerization inhibitor I to obtain agas-phase light component and a heavy component from the catalytic cracking reactor; and 3) feeding the heavy component obtained by the catalytic cracking reactor into a residue extrusion device, andseparating gas-phase light components and residues from the heavy component, wherein the gas-phase light components in the steps 1)-3) are mainly acrylic acid, methanol and methyl ester. The method has the advantages of being low in production cost, capable of saving energy, environmentally friendly and capable of easily separating products, and valuable components such as acrylic acid and methanol can be efficiently recycled.

Description

technical field [0001] The invention relates to a method for resource recovery of heavy components produced by a methyl acrylate plant. Background technique [0002] In the methyl acrylate industry, a large amount of methyl acrylate heavy components are produced by-product, and the composition is relatively complex. In addition to raw materials such as acrylic acid, there are also many Michael addition products of acrylic acid, methyl acrylate, water, and methanol. The specific composition of the by-product heavy component of methyl acrylate is: 29-31w% of acrylic acid, 26wt%-28wt% of methyl β-methoxypropionate, 13wt%-14wt% of methyl β-hydroxypropionate, 0.5wt% of methyl acrylate %-0.6w%, β-methoxypropionic acid 5-6w%, water 0.8w%-1.2w%, polymerization inhibitor (including hydroquinone, phenothiazine, ZJ701, etc., derived from methyl acrylate main process reactor and refining process), 3w%-6w%, etc. There is a high recovery value, but the recovery is difficult, especially ...

AI Technical Summary

Problems solved by technology

[0003] After years of development, the industry's current treatment plan for heavy components of methyl acrylate is: (1) incineration treatment: serious waste of resources; (2) pyrolysis using homogeneous catalysts such as sulfuric acid, p-toluenesulfonic acid, and methanesulfonic acid , but the above-mentioned catalyst has a low cracking rate and is easily thermally decomposed to form toluene and other by-products. Conventional polymerization inhibitors include hydroquinone, phenothiazine, ZJ-701 and other polymerization inhibitors, which are easy to carbonize and deteriorate to block the pipeline under high temperature conditions. The return of the product to the main process affects the product quality, and the equipment is highly corrosive; therefore, it is imperative to develop a production method with low cost, high stability and high recovery rate

[0004] Chinese published patent CN102516061A discloses a method that uses a spiral cracking furnace to recover and then purify the recovered product, which has problems such as difficult control of the cracking process, difficulty in designing the reactor, and easy polymerization blockage during the process.

[0005] Chinese published patent CN102173990 discloses a method using high-temperature cracking and atmospheric distillation to process heavy components, but the method has a low recovery rate and many by-products

[0006] Chinese published patent CN101932547A discloses a Michael addition product that uses p-toluenesulfonic acid, acrylic acid and esters to be mixed with water, and then cracked and recovered at 150°C. low rate problem

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