Preparation of macroporous catalysts and their performance in catalytic cracking of heavy oil

Two types of macroporous catalysts were prepared by using polystyrene particles (PS) and de-oiled vacuum residue (VR) as templates; their pore structure and catalytic performance in the catalytic cracking of heavy oil (FCC) were investigated. Compared with the traditional catalyst without using template, two catalysts using the PS and VR templates exhibit an increase of BET surface area by 38.0% and 46.2%, an increase of pore volume by 20.6% and 35.8%, and an increase of average pore size by 54.5 % and 27.3 %, respectively. Meanwhile, the conversions of heavy oil over two catalysts using the PS and VR templates are also increased by 9.8% and 12.2%, and the total liquid yields are increased by 10.2% and 7.3%, respectively, compared with that over the traditional catalyst. After enduring coke deposition in FCC, the activity of the macroporous catalysts was decreased as was expected, but still higher than that of the traditional catalyst at similar situation. The macroporous catalysts own a reasonable pore distribution due to the pore expansion with templates, which promotes the mass transfer in the macropores of the catalysts and provide them with higher tolerance towards coke deposition; these may contribute to their excellent performance in the catalytic cracking of heavy oil.