Hydrotreating of Egyptian Heavy Vacuum Gas Oil over Co-Mo/Carbon Nanotube Catalyst

Abstract

HE HYDROTREATING catalyst development is an essential ……..factor to produce clean fuels. The catalytic performance of CoMoS/CNT on Hydrotreating of the Egyptian heavy vacuum gas oil was investigated. Firstly the CNT was functionalized with concentrated HNO 3 . The Mo and Co wt% were loaded on CNT by impregnation methods. The catalyst was characterized by X-ray diffraction, Raman Spectroscopy, TEM, and BET. The hydrotreating experiments were conducted on autoclave reactor at various operating conditions of o C, pressure (20-60) bar, time (2-6) h and cat/oil ratio of 1:75, 33 and 10. The result indicated that the CoMoS/CNT was an efficient for the hydrotreating process. Also, the hydride-sulfurization (HDS) enhanced with increasing catalyst/oil ratio. Moreover, Results revealed that the optimum condition (temperature 350 o C, Pressure 40 bar, catalyst/oil ratio of 1:75 for 2 hr, was chosen.Additionally, even at low catalyst ratio of 1:75 an acceptable HDS% of 77.1 was achieved.Keywords: Hydrotreatment, Heavy vacuum gas oil (HVGO), Carbon nanotubes and CoMo/CNT.Due to economical and pollution control aspects, up 2010 the world legislations limited the sulfur content in fuels to <15 ppm (1)(2)(3)(4) . In order to meet this challenge, Nemours efforts to develop the hydrotreatment process, responsible for S and N removal, were potentially developed. Commercially, the MoS promoted by Co or Ni and supported on γ-Al 2 O 3 are the most active catalysts for hydrotreating process (5)(6) . The Co-Mo based catalyst is highly selective for HDS whereas NiMo based catalyst is more selective for hydrodenitrogenation (HDN) and hydrogenation. consequently, Ni-Mo based catalysts consumes higher hydrogen than Co-Mo based catalysts for the same extent of HDS with identical feed (7) . Despite the good thermal and textural properties and the high metal dispersion ability of γ-Al 2 O 3 (8) , it forms a strong metal-support interaction (9) .This interaction prohibits the complete metals sulfidation which decline the required active sites (10) .