Method for synthesizing acetonitrile through one-step ammoniating method with acetic acid

Abstract

The invention discloses a method for synthesizing acetonitrile through a one-step ammoniating method with acetic acid. The method comprises the following steps of: (1) reacting acetic acid with liquid ammonia in a fixed-bed reactor provided with a catalyst of aluminum oxide to generate a mixed gas containing the acetonitrile; and (2) continuously refining the gas mixture to obtain an acetonitrileproduct. By adopting the method, the acetonitrile product is relatively pure, the purity can reach more than 99.9%, the separation process is relatively simple, the process is short, the energy consumption in the production process is low, the energy consumption of a unit product is about 40% of the energy consumption with a by-product method, and the cost is lower. The separation process adopts a physical separation method, and avoids the problem of generating a great deal of wastewater and waste gas in the chemical process in the by-product method. Meanwhile, because the synthesis method isadopted, the limitation that the yield is restricted by the main product can be thoroughly avoided.

Description

technical field [0001] The invention relates to a method for synthesizing acetonitrile with acetic acid and ammonia as raw materials. Background technique [0002] Acetonitrile is an important fine chemical intermediate product and chemical solvent, and is an intermediate for the synthesis of medicines and spices, such as active medium solvents for the synthesis of vitamin B1, vitamin A, cortisone and amino acids, carbon amine drugs and other Intermediate solvent, which can replace chlorinated solvent; raw material for manufacturing triazine nitrogen fertilizer synergist; used as denaturant for acetic acid; used for preparing 2-picoline, triazine, ethylamine in organic synthesis , dipropionitrile, imidazole, propylene bisacetonitrile, etc. Acetonitrile can be used as an extractant for extracting butadiene and isoprene, a spinning flux for synthetic fibers and a solvent for special coatings such as vinyl coatings; it is used in the petroleum industry to remove tar, phenol an...

AI Technical Summary

Problems solved by technology

[0003] At present, the industrial acetonitrile products are all produced by the acrylonitrile by-product method, the output is limited (about 2.5% of the acrylonitrile output), and the quality is difficult to guarantee

Such as Chinese patent, application number CN 03112026.1 disclosed "method for synthesizing high-purity acetonitrile by ammoxidation of acetic acid", has described a kind of method for synthesizing high-purity acetonitrile by ammoxidation of ethanol, is the method for synthesizing acrylonitrile with reference to propylene ammoxidation, with ethanol, liquid Ammonia and oxygen are used as raw materials, and fluidized bed catalytic reaction technology is adopted. The process consists of three parts: reaction process, recovery process and refining process. Due to the long process flow, large investment and highly toxic hydrogen cyanide gas by-product, Therefore, there have been no reports of industrialization so far

[0004] Due to the special properties and excellent properties of acetonitrile, it is more and more widely used in chemical, pharmaceutical and pesticide industries. However, due to the current extreme shrinkage of the acrylonitrile market, the acetonitrile market is in a serious shortage. At the same time, because of the first acrylonitrile The continuous negative growth of acrylic fiber, a major market use, and the continuous decline in future market demand will exacerbate the contradiction between the supply and demand of its by-product acetonitrile. Therefore, it is urgent to develop a process route for the production of acetonitrile by chemical synthesis to meet the needs of relevant parties.