Synthesis process and enterprises of bisphenol A at home and abroad

Bisphenol A, with the scientific name of 22 bis (4-hydroxyphenyl) propane, is an important organic chemical raw material and an important derivative of phenol and acetone It is mainly used in the production of polycarbonate, epoxy resin, polysulfone resin, polyphenylene ether resin, unsaturated polyester resin and other polymer materials It can also be used to produce plasticizer, flame retardant, antioxidant, heat stabilizer, rubber antioxidant, pesticide, coating and other fine chemical products Bisphenol A is synthesized by condensation of two molecules of phenol and one molecule of acetone The catalyst for this reaction is acid catalyst The catalysts used in industry are sulfuric acid, hydrogen chloride and ion exchange resin The industrial application of these different types of catalysts constitutes different stages of the development of BPA technology 1 Sulfuric acid method the traditional production method of bisphenol A uses sulfuric acid as catalyst, phenol and acetone are condensed However, sulfuric acid process has poor selectivity, more than 40 kinds of impurities are generated, and it is difficult to separate Bisphenol a quality is poor, sulfuric acid consumption is large, forming a large number of waste acid and acid containing and phenol containing wastewater Environmental pollution is serious, and sulfuric acid process has been eliminated in developed countries 2 Hydrogen chloride method is the first method to produce bisphenol A with hydrogen chloride as catalyst in the United States Compared with sulfuric acid method, the catalyst hydrogen chloride is volatile and can be removed from the reaction system by vacuum distillation The quality of bisphenol A produced is better However, hydrogen chloride has strong corrosiveness, high requirements for the selection of equipment and pipeline materials, and increased investment At present, hydrogen chloride method is also gradually eliminated 3 In order to overcome the disadvantages of the above two methods, many countries began to study the synthesis of bisphenol A with ion exchange resin as catalyst in the early 1970s At present, industrialization has been realized, which has greatly changed the shortcomings of the traditional process The reaction substances are easy to separate, the post-treatment is simple, the ion exchange resin is less corrosive to the equipment, the reliability of the system operation is greatly improved, and the investment cost is not increased The condensation reaction is carried out under a large phenol ketone ratio Phenol is not only a reactant, but also a reaction solvent, which improves the selectivity of the condensation reaction The impurities in the condensation reaction products can be obtained high-quality bisphenol A products through a simple refining process Therefore, the technology of bisphenol a production by resin method has become the mainstream and development direction of bisphenol a production The world has its own bisphenol a technology manufacturers Ge, Bayer, Dow Chemical, Chiyoda, blachonia and other companies These manufacturers have many years of experience in the development and production of BPA, among which GE, Bayer, Dow and Chiyoda technologies represent the advanced level of BPA synthesis technology in the world.