Production of hydro-processed renewable jet fuel over SAPO-11-based catalyst

The role of single-metal-loaded on SAPO-11-based hydro-processing catalyst to produce renewable jet fuel was investigated in this work. First, three metals, nickel, cobalt, and molybdenum, were selected to be loaded on SAPO-11 separately and their activities were tested over the model feedstock, n-hexadecane. Among the three catalysts, nickel SAPO-11 shows the highest conversion of 70%. Second, the performance of Ni/SAPO-11, synthesized with (Ni/SAPO-11(CA)), and without (Ni/SAPO-11) citric acid was investigated with the hydro-processed alkanes derived from palm oil for the production of hydro-processed renewable jet fuel (HRJ). Catalyst metal particle size, structure, textural properties, acidity, and reduction degree were detected through transmission electron microscope (TEM), X-ray diffraction (XRD), N-2 adsorption/desorption, pyridine-adsorbed infrared spectroscopy (Py-IR), and temperature programmed reduction (TPR). The product compositions over the Ni/SAPO-11(CA) catalyst show higher selectivity toward the carbon chain length of jet fuel (C-8-C-14) for 48% compared to the Ni/SAPO-11. Through the Taguchi method, the optimal operating conditions were found to be: temperature of 380 degrees C, pressure of 52 bar, liquid hourly space velocity of 0.5 h(-1), and H-2-to-feedstock ratio of 1250, which yielded in 73% conversion to HRJ with 6.1 isomer-to-normal (I-to-N) alkane ratio. The derived cetane number (DCN) and the flash point of HRJ were also obtained to be 56 and 56 degrees C to confirm the compatibility of HRJ with conventional jet fuel.

Automated summary

This study investigates the role of single-metal-loaded SAPO-11-based catalysts in producing renewable jet fuel. Among the metals tested, nickel-loaded SAPO-11 showed the highest conversion rate, with Ni/SAPO-11(CA) displaying higher selectivity towards the carbon chain length of jet fuel compared to Ni/SAPO-11. Operating conditions such as temperature, pressure, and H-2-to-feedstock ratio were optimized using the Taguchi method, resulting in a high conversion rate to HRJ with a favorable isomer-to-normal alkane ratio.