Activity of NiMo and CoMo catalysts supported on Ti-pillared bentonite for converting waste cooking oil into green diesel

Green diesel can be produced from waste cooking oil through hydrodeoxygenation (HDO) employing NiMo and CoMo catalysts. These catalysts supported on Ti-pillared bentonite have been effectively prepared by pillaring bentonite with titanium as the pillaring agent, followed by double impregnation with NiMo and CoMo bimetals. The physicochemical properties of Ti-PILC, Mo/Ti-PILC, NiMo/Ti-PILC, and CoMo/Ti-PILC catalysts were characterized utilizing X-ray fluorescence (XRF), X-ray diffraction (XRD), Specific Surface Area Analysis, pore distribution assessments, Temperature-Programmed Desorption (TPD), and Scanning Electron Microscopy (SEM). The specific surface area and pore volume of bentonite increased significantly after Ti-pillaring. Both NiMo/Ti-PILC and CoMo/Ti-PILC catalysts effectively converted waste cooking oil into green diesel (C 14 -C 22 ). The green diesel yields were 57.07% for NiMo/Ti-PILC and 83.23% for CoMo/Ti-PILC. The CoMo/Ti-PILC catalyst demonstrated greater hydrodeoxygenation activity than the NiMo/Ti-PILC catalyst. The fatty acid composition of the feedstock plays a crucial role in determining both the optimal active metal configuration and the support catalyst. The primary product of hydrodeoxygenation of waste cooking oil comprises n-paraffins, unequivocally indicating the catalyst's proficiency in removing oxygen groups from oxidized compounds. This work demonstrates the potential of Ti-pillared bentonite as a cost-effective and high-performance catalyst support for advanced biofuel production from waste oils. • Pillared bentonite with titanium metal (Ti-PILC) was synthesized via sonication. • The catalytic activity of sulfided NiMo and CoMo supported on Ti-PILC demonstrated effective upgrading of waste cooking oil (WCO) to green diesel via hydrodeoxygenation (HDO). • The yield of green diesel (C 14 –C 22 ) exceeded 80%, particularly with the CoMo/Ti-PILC catalyst. • The fatty acid profile of the feedstock significantly influences the selection of active metals and support catalysts.