Cool GTL SM for the Conversion of Biogas and CO2 to Sustainable Aviation Fuel

This article describes the development and testing of a new low cost, streamlined gas to liquids(GTL) process named Cool GTL ^TM to make drop in sustainable aviation fuel (SAF) from bioderived gas or carbon dioxide and hydrogen. This system uses an improved catalyst in the reformer, Fischer Tropsch and upgrading reactor and an electric reformer. The Cool GTL system is simplified compared to the commercial state of the art. The Cool GTL system requires no membranes to adjust the compositions of synthesis gas and the vapor product from the Fischer Tropsch reactor goes directly to the upgrading reactor without removing the CO. The liquid hydrocarbon product made from this streamlined system is 50% high quality SAF meeting all SAF specification including freeze point. Trace levels of wax are produced which can be recycled to extinction. A novel electrically heated reformer was tested in the integrated system which uses internal resistive heaters in a bed of catalyst. This design eliminates the need for a pre-reformer for C2+ since the feed enters the catalyst bed at 537 °C and the temperature is increased in the reformer reactor through the internal heaters to reach the 808°C. The electric reformer is 10 percent of the size of a reformer using a furnace. By using bi-reforming catalyst both methane, C2+ and carbon dioxide can be converted to synthesis gas with a H2/CO ratio of 2.0-2.5 which can be fed directly to the Fisher Tropsch reactor without membranes to adjust the H2/CO ratio. More than 24 gallons of SAF was made using this integrated, simple, low cost, compact system. Statement of Industrial Relevance: This testing demonstrated a simplified streamlined GTL process which can be used to make SAF at small scales. Novelty or Significance : The Cool GTL is a new streamlined approach to converting biogas, bioderived gas or CO2 to SAF.