To provide a method for purifying or isolating 2,3,5-trimethyl-p- benzoquinone by surely removing intermediates and by-products formed during production of the compound and avoiding degradation of the component by diminishing the thermal stress caused by the treatment by separating the compound by the crystallization.
A method is provided for purifying 2,3,5-trimethyl-p-benzoquinone (TMQ) or isolating TMQ from a TMQ-containing mixture by separating by crystallizing preferably at -6 to 32°C. A TMQ-containing mixture to be purified or TMQ contains TMQ preferably at 1-99.999 wt.%, more preferably at 90-99.999 wt.%. The TMQ-containing mixture is formed preferably by the catalytic oxidation of trimethylphenol. TMQ is a useful intermediate for the production of trimethylhydroquinone which is a precursor for the synthesis of α-tocopherol.
BAUMANN DIETER
AQUILA WERNER DR
SCHUBERT JUERGEN
LECHTKEN PETER
