A clean hydroprocessing of jatropha oil into biofuels over a high performance Ni-HPW/CNT catalyst

The nickel (Ni) and phosphotungstic acid (HPW) supported on carbon nanotubes (CNT) were prepared by impregnation method for hydroprocessing of Jatropha oil. The Ni-HPW/CNT catalyst was characterized by XRD, XPS, FT-IR, N₂ adsorption-desorption, SEM, NH₃-TPD, and TGA. The effects of reaction parameters, such as reaction temperature (280-400°C), time-on-stream (0-100h), types of support, the amount of added HPW, and coking deposition were investigated. The cracking performance was evaluated by gas chromatography (GC). The yield of C15-C18 alkanes was 88.5wt.%, Iso/n ratio was 0.8 and conversion was 97.7% at 320°C, 3.0MPa and 1.0/h over the Ni-HPW/CNT catalyst, while the yield of <C15 alkanes reached 51.9wt.% at 400°C. The distribution of products could be adjusted by reaction temperature. The cracking performance was elevated by the addition of HPW and the electrical conductivity. The C15-C18 alkanes were further cracked through two cracking circulations. Meanwhile, the catalyst was used without sulfurization and the cracking process was green.