ISOMERIZATION OF XYLENE ISOMERS ON A PTRE-H-MORDENITE CATALYST

The isomerization of three xylene isomers was carried out on a catalyst containing 0.35 wt.-% platinum plus 0.35 wt.-% rhenium on hydrogen mordenite in a pulse catalytic microreactor positioned at the inlet of a gas chromatograph. Reactant injections were carried out at temperatures between 300 and 400-degrees-C with hydrogen gas flow at atmospheric pressure. High ratios of para-xylene in the product xylene isomer's mixture relative to the corresponding thermodynamic equilibrium values (2.9-3.5) were obtained, whereas the ratios of meta-xylene (0.33-0.69) were low and those of ortho-xylene were very low (0.093-0.18). However, relatively high dealkylation products (toluene and benzene) were obtained at higher temperatures. Disproportionation products (trimethylbenzenes) were not detected in the reaction products.