Catalytic pyrolysis of waste lubricating oil into jet fuel using aloe vera-modified CaO catalyst derived from marble waste

The improper disposal of waste lubricating oil (WLO) and marble waste poses serious environmental challenges, while their valorization into fuel-range products offers a promising circular-economy approach. Although marble waste can be used as a calcium-based catalyst precursor, its irregular and agglomerated morphology may affect the dispersion of active metal species and catalytic performance. This study developed an Aloe vera-assisted hydrothermal modification of marble-waste-derived CaO, followed by Ni and Mo impregnation, for the catalytic pyrolysis of WLO into fuel-range hydrocarbons. Marble waste was ground, sieved, dried, mixed with Aloe vera extract, and hydrothermally treated at 150 °C for 12 h. The resulting material was impregnated with 5 wt% Ni and 5 wt% Mo and calcined at 850 °C for 5 h to obtain the NiMo/MWAC catalyst. The synthesized materials were characterized using XRD, FTIR, FESEM–EDS, TEM, N2 adsorption–desorption, XPS, and CO2 -TPD analyses. The Aloe vera-assisted treatment modified the surface morphology and facilitated the distribution of Ni and Mo species on the calcium-based support. XRD and XPS confirmed the formation of CaO, NiO, and CaMoO4 phases and the presence of Ni2+ and Mo6+species. NiMo/MWAC exhibited the best catalytic performance, producing a maximum liquid yield of 51.86 wt% and promoting hydrocarbons in the jet-fuel range, particularly C13–C16. Response Surface Methodology showed that reaction temperature and catalyst loading were the most influential variables, whereas reaction time had a limited effect. The developed NiMo/MWAC catalyst provides a low-cost and sustainable route for the simultaneous valorization of marble waste and WLO into jet-fuel range hydrocarbons.

Text 127929.pdf - Published Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (20MB) Official URL or Download Paper: https://linkinghub.elsevier.com/retrieve/pii/S1026...

Actions (login required)

View Item