A two-feed simulated moving bed(SMB) was proposed to utilize the stationary phase more effectively.Zone I is disconnected with zone Ⅱ and zone Ⅲ is disconnected with zone IV.Two feeds are added to zones Ⅰ and Ⅲ

while two desorbents are added to zones Ⅱ and IV separately.The investigation on the movement of concentra-tion bands indicated that the tail of the strong retained solute and the front of the weak retained solute were eluted from zones Ⅰ and Ⅲ orderly

so the streams from zones Ⅰ and Ⅲ could be cut into different fractions to give the products with high purity.The two-feed SMB was used to separate α-tocopherol from its homologue mixture successfully

and could double the productivity if both feeds were identical to the feed in the conventional four-zone SMB.The solvent consumption could be reduced by reusing the middle fraction without solutes.