Non-¦Á-tocopherol Response In Transition

Since α-tocopherol has special biological activities, it is important to convert non-α-tocopherols to a-tocopherol. Experiments were divided into two parts, one was primary research on the autoclave and the other was primary research on the fixed bed.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 the catalysts of benzenesulfonic acid and 5% Pd/C in an autoclave. Effects of various conditions have been studied. The preferable reaction conditions are: temperature 180℃ 'to 200℃, pressure 5 MPa, acid concentration 0.5 g/100 ml ethanol, weight ratio of Pd/C to tocopherols 7.1 g/100 g, and reaction time 5 h. A product with the a-tocopherol content of 80% has been obtained by using a raw material with a total tocopherols content of 80.54%. The conversion of non-α-tocopherols is almost 100%, and the mole yield of α-tocopherol is more than 90%.During the primary research on the fixed bed, three influencing factors were considered: temperature, the concentration of tocopherols and the concentration of benzenesulfonic acid. The results showed that the preferable reaction conditions are: temperature 180℃, the concentration of tocopherols 15g/400ml methol, the concentration of benzensulfonic acid 4.0g/400ml methol.