Single-step catalytic deoxygenation-cracking of tung oil to bio-jet fuel over CoW/silica-alumina catalysts

• Published in: Fuel (Guildford) 2022-10, Vol.325, p.124917, Article 124917
• Main Authors: Asikin-Mijan, N., AbdulKareem-Alsultan, G., Mastuli, M.S., Salmiaton, A., Azuwa Mohamed, Mohamad, Lee, H.V., Taufiq-Yap, Y.H.
• Format: Article
• Language: English
• Subjects: Cobalt; Deoxygenation; Jet fuel; Tung oil; Tungsten
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2022.124917

•Development of CoW/SA catalyst for effective deoxygenation-cracking of tung oil into jet fuel hydrocarbons.•Weak + medium acid sites, metal dispersivity and synergistic effect play important role in the progressive deoxygenation and cracking activity.•The tung oil-jet qualities are complied with standard Jet A-1 standard.•The tung oil-jet exhibited excellent cold properties and superior combustion characteristic. Bifunctional Co-W catalysts with variable Co-W dosages on silica-alumina (SA) were prepared and tested for the catalytic deoxygenation-cracking of tung oil (TO) for the production of jet fuel (n-(C10-C16)) fractions. The CoW/SA catalyst appeared to be most active (hydrocarbon yield = 69%, jet fuel selectivity = 60%) and outperformed the monometallic Co and W analogues. Based on the effect of metal dosage, Co– and W-rich catalysts do not provide a workable approach in enhancing deoxygenation-cracking of the TO for jet fuel production, and overly cracking can be successfully controlled at lower metal dosages (5 wt% Co, 10 wt% W). The CoW/SA reusability study showed a consistent deoxygenation-cracking ability for four runs with hydrocarbon yields within the range of 77–84% and 64–77% jet fuel selectivity. GCMS analysis and physicochemical properties of TO oil fuel (TO-gasoline, TO-jet, TO diesel) confirmed that rich aromatic species in TO-diesel negatively affected the quality of the fuels. TO-fuels with a short chain had better combustion properties than those with a longer chain hydrocarbon. The TO-jet qualities are complied with standard Jet A-1 in accordance to ASTM D1655 and DEF STAN 91–91 specification standards. The TO-jet also exhibited excellent cold properties and superior combustion characteristic than Jet A-1.