Abstract: The conversion of ethylbenzene to xylene was studied. The effects of metal dispersion, physical and chemical properties of the carrier，and the strength of B acid on the isomerization of ethylbenzene were investigated. The results showed that the conversion ability of ethylbenzene reaches the best level when the dispersion of platinum is 7.1 %. The size of carrier particles has a great influence on the dispersion of metal, and the conversion of ethylbenzene increases with the decreases of carrier particles and increases of metal dispersion. The ethylbenzene conversion capacity is different with structures of molecular sieves. When the ammonia desorption temperature is 350 ~ 450 ℃, the ethylbenzene conversion rate increases due to increase of B acid amount. Based on the above studies, a new type of catalyst RIC-270 for isomerization of C8 aromatics was developed by Research Institute of Petroleum Processing of SINOPEC. The industrial results showed that compared with RIC-200 catalyst, the ethylbenzene conversion capacity of RIC-270 is obviously improved, and ethylbenzene conversion reaches 81.7 % at equilibrium. The lower content of C8 non-aromatics effectively improves para-xylene content in the reaction product.

Key words: ethylbenzene conversion, metal function, carrier property, acidic function