KINETIC-STUDY OF NAPHTHALENE HYDROGENATION OVER PT/AL2O3 CATALYST

The hydrogenation of the biaromatic compound naphthalene was studied in a trickle bed reactor at 473-533 K, 1.7-8.7 MPa, and 1.5-8.0 liquid hourly space velocity (LHSV) over Pt/Al2O3 catalyst. The hydrogenation activity and selectivity were investigated by using a reaction network including isomerization of decalin and a power-law kinetic model. The rates of tetralin hydrogenation and cis-decalin isomerization could be described by pseudo-first-order kinetics in excess hydrogen. The apparent activation energies for hydrogenation of tetralin to cis-decalin and trans-decalin and isomerization of cis-decalin are 9.88, 7.25, and 14.75 kcal/mol, respectively. These values match those reported in the literature. The reaction orders by hydrogen for the hydrogenation of tetralin to cis-decalin and trans-decalin are 1.88 and 1.06, respectively. For the isomerization of cis-decalin, the reaction order of hydrogen decreases with increasing pressure and approaches 0 at pressure higher than 5.17 MPa.