Optimization of catalytic cracking process for upgrading camelina oil to hydrocarbon biofuel

• Hydrocarbon biofuel produced from camelina oil for bio-jet fuel production was targeted.
• Optimization of catalytic cracking conditions for hydrocarbon biofuel production was carried out.
• Effect of three upgrading conditions on hydrocarbon biofuel yield and quality was evaluated.
• The order of significant factors was oil extraction press frequency ≻ reaction temperature ≻ liquid hourly space velocity.

Catalytic cracking of camelina oil over Zn/ZSM-5 catalyst in a fixed-bed tubular reactor was investigated. An optimization study on the catalytic cracking conditions based on nine well-planned orthogonal experiments was carried out. Three main operation conditions including reaction temperature, liquid hourly space velocity and oil extraction press frequency were studied to examine their effects on the yield and quality of hydrocarbon biofuel produced. Characterization of the catalyst, hydrocarbon biofuel and non-condensable gas was conducted. There was no significant difference between the bulk structures of fresh Zn/ZSM-5 and used Zn/ZSM-5. Small ZnO particles dispersed well on the parent ZSM-5. Hydrocarbon biofuel contained 65.18% hydrocarbons and its properties including dynamic viscosity, density and higher heating value were improved after upgrading, compared to camelina oil. It was found that the oil extraction press frequency was the most important factor and liquid hourly space velocity was the least important factor for the hydrocarbon biofuel production. In addition, the optimum conditions for camelina oil upgrading were a combination of reaction temperature of 550 °C, a liquid hourly space velocity of 1.0 h−1 and an oil extraction press frequency of 15 Hz.