Abstract: The model of simulated moving bed(SMB) for xylene separation is established, considering the axial dispersion in the void volume，based on the adsorption equilibrium constants and mass transfer coefficients obtained from experiments. The simulation results and the industrial plant data are concordant. The effect of pre-saturated components, operation parameters on SMB process is investigated. Results show, reduction of ethylbenzene, meta-xylene and ortho-xylene in the pre-saturated components, increasing feed rate and purification zone flowrate are all benefit for shortening the start-up time of SMB process.

Key words: simulated moving bed, para-xylene, adsorption