Comparison of hydrogenation and mild hydrocracking activities of Pt-supported catalysts

Six Pt-supported catalysts based on mordenite, pillared clay, delaminated clay and Al-MCM41 were tested for hydrogenation and mild hydrocracking activities in processing a middle distillate derived from Canadian oil sands. Experiments were performed in a fixed-bed microreactor between 260 and 380 °C, at a total pressure of 10.3 MPa and a LHSV of 1.0 h−1. The results showed that, except for the untreated mordenite based catalyst, the other catalysts all had suitable pore structures to accommodate molecules as large as three-ring cycloparaffins and to convert them into smaller molecules. Dealumination made mordenite a better mild hydrocracking catalyst due to the creation of mesopores and macropores, and the reduction of surface acidity. At 320 °C, pillared clay based catalysts had the highest hydrogenation activity followed by Al-MCM41, delaminated clay and mordenite based catalysts. Delaminated clay based catalyst, despite producing the highest diesel yield at the same conversion of 343 °C+ fraction, required the highest reaction temperatures. Thus, Pt/pillared clay and Pt/Al-MCM41 were the best overall catalysts, producing high aromatic conversion, high diesel yield and relatively low reaction temperature to reach 30% conversion of 343 °C+ fraction.