Aromatic hydrogenation of distillates over SiO2-Al2O3-supported noble metal catalysts

In order to develop a new sulfur-tolerant noble metal catalyst with signifi cantly increased catalytic activity for aromatic hydrogenation, the screeni ng tests of the various non-zeolitic noble metal catalysts were carried out with hydrotreated light cycle oil (LCO)/straight-run light gas oil (SRLGO) feed containing 32-34 vol% aromatics and 172-474 ppm sulfur at a temperatu re of 573 K, hydrogen pressure of 4.9 MPa, and LHSV of 1.5 h(-1). The Pt-Pd /SiO2-Al2O3 catalyst was the most highly active catalyst for aromatic hydro genation under the conditions applied. The co-existence of Pt with Pd on Si O2-Al2O3 remarkably enhanced the catalytic activity, which depended on the Pd/(Pt + Pd) weight ratio and reached a maximum of about 0.7 Pd/(Pt + Pd) w eight ratio. Furthermore, the long-term stability test under industrial ope rating conditions demonstrated the excellent stability of the Pd-Pd/SiO2-Al 2O3 catalyst. (C) 2000 Elsevier Science B.V. All rights reserved.