Preparation method of 2,6-diphenyl phenol

Abstract

The invention relates to a preparation method of 2,6-diphenyl phenol. The preparation method is characterized in that 2,6-diphenyl phenol is prepared in a tubular fixed bed reactor aiming at overcoming the defects that operating conditions are difficult to control, continuity is poor, mechanical strength of a catalyst is low, the catalyst is easy to coke and products and the catalyst are difficult to separate in the prior art; the catalyst is loaded, temperature is controlled to be 250-300 DEG C, shielding gas is introduced to realize gas shielding, trimeric ketone obtained through cyclohexanone self-condensation reaction is added into the tubular fixed bed reactor, liquid hourly space velocity is 0.1-10 / h, the trimeric ketone flows out from the tubular fixed bed reactor after reaction is carried out in the presence of the catalyst, reaction product flowed out is collected, the reaction product is recrystallized in solvent, and vacuum filtering and drying are carried out, thus 2,6-diphenyl phenol is obtained. The preparation method provided by the invention has the advantages that raw materials are economic, continuous operation can be realized, the preparation method is convenient to control, the mechanical strength of the catalyst is high, the catalyst is difficult to coke and can be completely separated from the product, per-pass conversion of the trimeric ketone is high, and yield of the target product is high.

Description

technical field [0001] The present invention relates to a kind of preparation method of 2,6-diphenylphenol, specifically, relate to a kind of preparation method of the 2,6-diphenylphenol that takes cyclohexanone self-condensation trimer ketone as raw material . Background technique [0002] 2,6-diphenylphenol (2,6-diphenylphenol, referred to as DPP) is an important chemical raw material, the appearance is white crystalline powder, the melting point is 101 ℃ ~ 103 ℃, slightly soluble in water, easily soluble in methanol, Organic solvents such as ethanol, acetone, benzene, dichlorobenzene, and trichloroethylene, and alkaline solutions. It is widely used in the fields of dyes, insecticides, narcotics, adsorption materials, special engineering plastics, insulating materials and antioxidants. With the continuous expansion of the use of 2,6-diphenylphenol in recent years, the demand has increased rapidly, and the development prospect is extremely broad. [0003] In recent decad...

AI Technical Summary

Problems solved by technology

The advantage of this process is that the raw material cyclohexanone is economical, less environmental pollution, less process steps, and suitable for large-scale industrial production; the disadvantage is that after the first step cyclohexanone is self-condensed under the action of a catalyst to obtain trimer ketone, the second step In the second step, Pd / C catalyst is added to the trimerone container, and the dehydrogenation reaction is carried out at 260-290 ° C to prepare 2,6-diphenylphenol. The operating conditions are not easy to control, the continuity is poor, the mechanical strength of the catalyst is low, and it is easy to coke. Product and catalyst are difficult to separate

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