OPP Synthesis

Many processes for the production of o-phenylphenol by organic synthesis technology have been developed at home and abroad. According to the different raw materials used, there are mainly the following: biphenyl embracing method, which heats 2-biphenylene oxide with metal sodium at about 200 ℃, and then decomposes the product with acid to obtain OPP; Aminobiphenyl diazotization hydrolysis method, diazotization of 2-aminobiphenyl, and hydrolysis; Biphenyl sulfonation hydrolysis method: sulfonate biphenyl with oleum sulfate, alkali melt with caustic soda, and then acidize the obtained product (there are para products besides ortho products), with unit consumption of 1.13t/t biphenyl, 0.77t/t oleum sulfate, and 0.59t/t caustic soda; Cyclohexanone condensation dehydrogenation method: cyclohexanone is condensed in liquid phase to synthesize dimer ketone, and dimer ketone is dehydrogenated to OPP by gas phase catalysis, and then pure OPP is obtained by distillation and recrystallization; Chlorobenzene phenol coupling method was used to synthesize o-phenylphenol from chlorobenzene and phenol by phase transfer catalysis. This paper mainly introduces the production process of o-phenylphenol by cyclohexanone condensation dehydrogenation, which is an advanced process.