Development Prospect Of Partial Benzene Anhydride With Pharmaceutical Intermediates
Nov 30, 2018

The industrial production methods of phthalic anhydride were studied and developed abroad as early as the 1950s. 1962 the United States Amoco Company first used partial toluene liquid-phase air oxidation method to achieve industrial production, and in 1968 in the United States Ino Joliete plant built a kt/a production plant. 1993 the company built a set of kt/a production plants at the Geel plant in Belgium using the new technology of the improved partial toluene liquid-phase air oxidation process, and the 1968 Japan Competition Company and Catalyst Chemical Company used air oxidation method to put into production separately ; In 1970, the German company Saarbergwerk a production plant using a partial toluene nitric acid oxidation method (later, due to high production costs, serious three wastes problems, operational hazards and stop production); In 1985, Mitsubishi Gas Chemical Co., Ltd., Japan developed successfully with paraxylene as raw material, A new process for the production of MGC anhydride by air oxidation of aromatic aldehyde aqueous solution (i.e., the method of high-kt/a) has been completed, and a set of plants of the plant has been built in the water Island. After the installation and commissioning of the device, the market for Amoco anhydride, formerly monopolized by the United States company, has undergone great changes, and the Japanese market (which accounts for about one-third of the world market) is now occupied by Mitsubishi Gas Chemical Company. In addition, Japan's distillation industry company, Mitsui East pressure company have also been built with thousands of tons of benzene anhydride production plant.

At present, the production capacity of the world's kt/a anhydride is about $31.21%, of which the production capacity of the Bp-amoco company is accounted for by about half of the world's total production capacity of phthalic anhydride. The main manufacturers of phthalic anhydride in China: The research and development of phthalic anhydride in China started late. In the late 1960s, Heilongjiang Petrochemical Research Institute and Nanjing Lacquer Factory jointly carried out the research work of partial benzene anhydride by liquid phase oxidation of offset toluene, and established a set of T/A pilot test device in Nanjing Lacquer factory. The device uses acetic acid as solvent, cobalt acetate, manganese acetate and four bromine ethane as catalysts, the reaction temperature is 170 ℃, the oxidation pressure is 2.2 MPa, the oxidation products first buck flash evaporation, and then decompression distillation recovery solvent. The yield of 100%~110% anhydride to partial toluene is 95%~98%, and the purity of the product is in the same order, and the test device is stopped midway because the engineering problem is difficult to solve. Subsequently, the Heilongjiang Institute of Petroleum Chemistry and Harbin Petrochemical plant in cooperation with the construction of a set of t/a anhydride production plant, Operation for half a year is also discontinued for any reason. Later, Harbin Petrochemical Plant also expanded the device to 3 t/a, but due to the use of continuous production process, the technical difficulties greatly increased, the commissioning of many problems difficult to solve, and later forced to stop production, only recently re-driving to produce; 1992 Jiangsu Wuxi Jianghai Chemical Co., Ltd. built a t/a production plant ; 1995 Jiangsu Jiangyin changqing vinegar anhydride factory built a set of t/a production plant, the operation is relatively normal, product quality can meet user requirements. At the end of 1997, the factory built a new set of 1 t/a years production plant, trial production situation is good, compared with the original device, the product quality is significantly improved, the consumption is significantly reduced. At present, the total production capacity of phthalic anhydride in China is 7 t/a, the output is less than 2 t/a, the consumption is about 12.8 kt/a, mainly using the Gap method production process.


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