Non-a-tocopherols are hydroxymethylated and hydrogenated to produce a-tocopherol in one pot process by simultaneously reacting with paraformaldehyde and hydrogen in the presence of catalysts of benzenesulfonic acid and 5% Pd/C in an autoclave. Effects of various operation conditions have been studied. The preferable reaction conditions are: temperature 180℃ to 200℃, pressure 5.0 MPa, acid concentration 0.5 g/100 ml ethanol, mass ratio of Pd/C to tocopherols 7.1g/100g, and reaction time 5.0 h. A product with a-tocopherol content of 80% was obtained by using a raw material with a total tocopherols content of 80.54%. The conversion of non-a-tocopherols is almost 100%, and the mole yield of a-tocopherol is more than 90%.
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