METHOD FOR PRODUCTION OF PHENOLS Russian patent published in 1996 - IPC

FIELD: production of alkylphenols. SUBSTANCE: alkylphenols having formula I where each of R₁, R₂, R₃, R₄, R₅, represents hydrogen or C₁-C₆-alkyl, cycloalkyl, aryl, arylalkyl or amino group and at least R₁ or R₅ represents hydrogen are prepared by oxidizing decarboxylation of suitable arylcarboxylic acid. Said process is carried out in liquid phase with the help of oxygen-containing gas, copper catalyst which contains Cu(+1) being used. Method involves production of intermediate copper arylcarboxylate, its decomposition and hydrolysis thus obtained ester. The process is followed by regeneration of catalyst which takes place simultaneously with separation of thus prepared phenol. Said decarboxylation is carried out at 191-270 C in the presence of water at pressure 1 kg/cm², oxygen being added during said process. Quantity of said oxygen is so that residual content of copper as Cu (I) provides selective production more than 92 % of phenol. Preferred quantity of oxygen is so that residual quantity of Cu(I) is 0.015 % of total mass of copper. Quantity of oxygen in mentioned above oxygen-containing gas is 1-15 vol %. Mentioned above catalyst may contain cocatalyst, concentration of copper in metal form is 1-10 % of mass of reaction mixture. EFFECT: improves efficiency of method.