Green diesel production via continuous hydrotreatment of triglycerides over mesostructured γ-alumina supported NiMo/CoMo catalysts

Abstract

In the present study, the deoxygenation of canola oil was performed in a continuous fix-bed reactor. Wormhole-like mesostructured γ-alumina with nano-sized crystalline domains and pores in the range of 8nm was one-pot synthesized using polymeric template assisted sol-gel method via evaporation-induced self-assembly (EISA). Nanoporous catalysts were prepared by employing the incipient wetness co-impregnation method followed by a calcination step, 15wt% MoO3 and 3wt% NiO or CoO, were impregnated on the nanoporous support. Both catalysts favored the hydrodeoxygenation reaction pathway, and the liquid hydrocarbons consisted mostly of C15–C18 n-alkanes. The effects of LHSV and temperature on the liquid product composition were investigated in the range of, LHSV: 1 to 3h−1, and temperature of 325 to 400°C while keeping other reaction conditions constant at a pressure of 450psi and H2/oil of 600mLmL−1. Slightly better catalytic activity was perceived for NiMo-S/γ-alumina at higher LHSV compared to CoMo-S γ-alumina catalyst. The liquid conversion on NiMo-S/γ-alumina is higher than that on CoMo-S/γ-alumina over the temperature range of 325 to 350°C. At 375°C, the conversion reached 100% over both catalysts. The production of green diesel range liquid products over NiMo-S/γ-alumina and CoMo-S/γ-alumina was found optimal at 325°C and 1h−1 LHSV.