back-arrow

Diesel & Other Fischer-Tropsch Liquids

Discover how to make clean diesel and other liquid fuels using FastOx gasification.

Production

Fischer-Tropsch (FT) systems convert syngas through a series of chemical reactions over a catalysts (typically cobalt and iron) to produce sulfur-free and aromatic-free renewable diesel. The diesel we generate is twenty times cleaner than even the ultra-low sulfur diesel standards in California.
The catalytic conversions sequester carbon from carbon monoxide and string them into long carbon chains. They then attach Hydrogen molecules to the carbon chains to create hydrocarbons. By varying the catalyst composition and adjusting the process conditions (pressure and temperature), it is possible to control the polymerization chain growth reactions of these hydrocarbon chains. This enables the production of a range of products including light hydrocarbons, liquefied petroleum gas, naphtha, diesel, and wax fractions. Typical operating conditions for FT synthesis of long-chain products, such as renewable diesel, are 200–250°C (390-480°F) and pressures of 25–60 bar.
The discharge of the FT reactor contains byproduct water (pressurized to stay in the liquid form), low molecular weight hydrocarbons (gases), and a wide range of liquid hydrocarbons that can include naphtha, diesel, and wax cuts. These can be separated by use of a three-phase separator. The tail-gas can be recycled to the FastOx gasifier or used to generate additional electricity on site. The purified water is cooled and used within the plant and the liquid hydrocarbons continue on to a fractionator. The fractionator, as the name implies, separates appropriate fractions of the liquid hydrocarbons to produce the final desired product in the proper quantities.