A device for the industrial production of hydroxyacetonitrile

Abstract

The invention relates to a device for industrially producing hydroxyl acetonitrile. The device adopts a hydrocyanic-acid hydroxymethylation method for production and comprises a first-order reaction unit and a second-order reaction unit, wherein the first-order reaction unit comprises a first-order reactor and a first-order circulating tank connected with the first-order reactor; the second-order reaction unit comprises a second-order reactor and a second-order circulating tank connected with the second-order reactor; and the first-order reactor is also respectively connected with the second-order reactor and the second-order circulating tank. The device is characterized in that during operation, the first-order reaction unit uses low-concentration formaldehyde to absorb hydrocyanic acid so as to obtain first-order absorbing liquid; the second-order reaction unit uses high-concentration formaldehyde to absorb the hydrocyanic acid which is not completely absorbed so as to obtain second-order absorbing liquid; and then the second-order absorbing liquid enters the first-order reaction unit for continuous reaction. The device has the advantages that the absorption of the hydrocyanic acid by using the formaldehyde material with high concentration and low concentration is realized, the utilization rate of the hydrocyanic acid is high, the residual amount of the formaldehyde in an obtained product is low, and high-efficiency industrial production of the hydroxyl acetonitrile can be carried out.

Description

technical field [0001] The invention relates to an industrialized chemical production device, in particular to a device for industrialized production of hydroxyacetonitrile. Background technique [0002] Hydroxyacetonitrile, also known as glycolonitrile or formaldehyde cyanohydrin, is a colorless to light yellow liquid, highly toxic, can volatilize a mixed gas containing hydrocyanic acid in an open container, can dissolve some metals to form complexes, and is soluble It is widely used in chemical industry, dyestuff, medicine, pesticide and other fields. [0003] The preparation methods of hydroxyacetonitrile mainly include acetonitrile oxidation method and hydrocyanic acid hydroxymethylation method. The specific process of hydrocyanic acid methylolation method is: liquid formaldehyde and certain concentration of hydrogen cyanide gas are directly added to form hydroxyacetonitrile in a normal pressure equipment under an appropriate acid-base environment. Although the synthes...

AI Technical Summary

Problems solved by technology

In the case of optimizing the raw materials and reaction conditions, the process is still troubled by the polymer produced in the reaction, which is an inherent defect that cannot be overcome by the process design: in the production process, although the liquid and gas phases of the raw materials are advanced The materials are all continuous, but the discharge is intermittent, and it is not continuous production in the true sense (the raw materials are continuously fed, the reaction is continuously carried out and the product is continuously withdrawn); along with the reaction, the accumulated hydroxyacetonitrile is getting more and more More, on the one hand, the reaction rate will be reduced and the conversion rate of raw materials will be reduced; on the other hand, under the reaction conditions, the generated products will be prone to polymerization or decomposition, which will reduce the product quality

[0010] Therefore, under the situation of utilizing industrialized raw materials and large-scale production, still lack a kind of real continuous high yield, the production device and the technique of high-quality hydroxyacetonitrile

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