Effect of preparation on hydroisodewaxing performance for diesel fuel of NiW/SAPO-11 catalysts

Catalysts for hydroisodewaxing were prepared by SAPO-11 zeolite instead of ZSM-5 zeolite with nickel and tungsten as metal components. The catalysts were characterized by using XRD, BET and Py-IR. Using Changqing straight-run diesel oil as raw material, we evaluated the hydroisoderwaxing performance of the NiW/SAPO-11 catalysts prepared by different methods. The catalytic performance evaluation was performed on a pressurized fixed-bed microreactor. The result shows that the NiW/SAPO-11 catalyst prepared by mixing-kneading Ni first and then impregnating W active component has better hydroisodewaxing performance. At the reaction conditions of 340 ℃, 4.0 MPa, LHSV 1.0 h^-1 and hydrogen to oil volume ratio of 500:1, the freezing point of the diesel oil was decreased from 0 ℃ to -28 ℃, and the diesel yield was as high as 96.0%.