Linyi Yu Heng Mechanical Chemical Co., Ltd.
Contact: Chairman - Chan Hua -13905390882
Manager - Shang Jun Yu -15376910008
Contact phone: 0539-5778777
Company fax: 0539-5778717
Contact Q Q:948562665
Micro signal: 15376910008
Company mailbox: 948568665@qq.com
Company website: www.yuhengjixie.cn
Address: Xinqiao Town, Lanshan District, Linyi, Shandong
Glyoxylic acid is a widely used fine chemicals, mainly used in the production of pharmaceutical chemicals such as hydroxyphenylhydantoin, vanillin and hydroxyphosphonic acid. Glyoxylic acid production methods are mainly oxidation of glyoxylic acid, oxalic acid reduction and ozonation of maleic anhydride, among which two aldehyde oxidation has been commercialized in two. The oxidation of ethyl two aldehyde is mainly based on the preparation of glyoxylic acid by using different oxidants in acid medium to oxidize ethyl two aldehyde. The patent disclosed oxidants are mainly nitric acid, nitrogen oxide, chlorine gas, air and its combination. At present, the process of industrial production mainly uses nitric acid and air combination of two aldehyde nitric acid oxidation method, its chemical reaction is as follows CHOCHO+HN03+02= CHOCOOH +NOx +N2+H20 reaction process, most nitric acid is converted to no recycling nitrogen and Nitrous Oxide greenhouse gas, production needs to continue to supplement nitric acid, at the same time producing a large amount of nitric acid. Difficult to deal with nitrogen oxides tail gas, causing a certain degree of environmental pollution. In order to eliminate the pollution of nitrogen oxide tail gas and reduce the production cost of glyoxylic acid, the Japanese competition Lo company patents JP57091950 (1982+8), JP58029739 (1983-2-22) and JP58198437 (1983-11-18) disclosed the preparation of glyoxylic acid by the oxidation of acetaldehyde with chlorine gas. The chemical reaction, such as CHOCHO+H20+Cl2= CHOCOOH +2HC1 reaction, produces a large amount of acid. When the concentration of hydrochloric acid reaches 13%-15%, the rate of oxidation reaction decreases rapidly, the conversion rate of ethylene two aldehyde is no longer increased, and the yield of glyoxylic acid decreases. By reducing the concentration of hydrochloric acid by diluting the reaction solution, the concentration of glyoxylic acid in the finished reaction liquid is too low, which complicates the post-processing process. The American patent US4503246 (1985-3-5) disclosed that a small amount of bromine catalyst was added to the oxidation process of chlorine gas to further improve the oxidation rate and conversion rate of B two aldehyde, but the separation was difficult after the addition of bromine, and the residual bromine affected the subsequent reaction, and the production cost of glyoxylic acid was increased. With the expansion of the product market of the two aldehyde oxidizer manufacturer, higher requirements are put forward for its product quality, production cost and environmental protection. The Residual Ethyl two aldehyde in the glyoxylic acid has a great influence on the subsequent application, and the separation cost of Residual Ethyl two aldehyde is high, and the conversion rate of two aldehyde is more than 95% in production. The high concentration of hydrochloric acid in the reaction solution makes the post-processing of the products more difficult, hoping to reduce the concentration of hydrochloric acid in the finished liquid.