The production of renewable aviation fuel from waste cooking oil. Part II: Catalytic hydro-cracking/isomerization of hydro-processed alkanes into jet fuel range products

Abstract

In this study, the surrogates of long chain paraffins produced from waste cooking oil through hydro-processing was hydro-cracked and hydro-isomerized for studying the process for producing renewable aviation fuel, through carrying out the experiments with varying reaction temperature, pressure, H2-to-alkane ratio and weight hourly space velocity (WHSV) over the home-made NiAg/SAPO(silicoaluminophosphate)-11catalyst. The data of conversion, selectivity, isomer yield and isomer-to-normal (I-to-N) alkane ratio were determined for evaluating the performance of the catalyst. The catalyst characterizations of the fresh and spent catalysts were examined through the technologies of Scanning Electron Microscopy (SEM), powder X-ray diffraction (XRD), thermo-gravimetric analysis (TGA) and fourier-transform infrared (FTIR) spectroscopy. It was found that the rearrangement of vapor-liquid equilibrium and increase in residence time by adjusting the operating conditions improved the performance of hydro-cracking/isomerization. In addition, based on the results of catalyst characterizations, the unreacted feed was dispersed onto the surface of the catalyst, expected to deactivate the catalyst.