Aromatic hydrogenation of distillates over SiO_2-Al_2O_3-supported noble metal catalysts

摘要

In order to develop a new sulfur-tolerant noble metal catalyst with significantly increased catalytic activity for aromatic hydrogenation, the screening 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 temperature of 573 K, hydrogen pressure of 4.9 MPa, and LHSV of 1.5h~(-1). The Pt-Pd/SiO_2-Al_2O_3 catalyst was the most hyghly active catalyst for aromatic hydrogenation under the conditions applied. The co-existence of Pt with Pd on SiO_2-Al-2O_3 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) weight ratio. Furthermore, the long-term stability test under industrial operating conditions demonstrated the excellent stability of the Pt-Pd/SiO_2-Al_2O_3 catalyst.