FT vs HEFA

FT (Fischer–Tropsch) and HEFA (Hydroprocessed Esters and Fatty Acids) are two different pathways used to produce sustainable aviation fuel from different feedstocks and chemical processes.

Both pathways produce aviation fuel blending components approved for commercial use, but they differ in feedstock flexibility, intermediate chemistry, and scale characteristics.

What is the difference between FT and HEFA?

FT uses synthesis gas as the intermediate feedstock, while HEFA uses oils and fats as the primary feedstock.

FT pathway

Feedstocks are first converted into synthesis gas containing hydrogen and carbon monoxide.

 

HEFA pathway

Feedstocks such as used cooking oil, animal fats, or vegetable oils are hydroprocessed directly.

 

This creates two fundamentally different production routes.

Fischer-Tropsch FAQ - image of oil slick

What feedstocks are used in FT and HEFA?

FT and HEFA differ primarily in what carbon sources they can process.

FT feedstocks

  • Biomass
  • Municipal solid waste
  • Biogas
  • Renewable hydrogen and captured CO₂

 

HEFA feedstocks

  • Used cooking oil
  • Tallow
  • Vegetable oils
  • Other lipid-based feedstocks

 

FT pathways generally begin with carbon sources converted to syngas, while HEFA depends on lipid availability.

How do FT and HEFA produce aviation fuel?

FT and HEFA use different chemistry to produce jet-range hydrocarbons.

FT production

 

Syngas is converted through Fischer-Tropsch synthesis into synthetic hydrocarbons, which are then upgraded into aviation fuel fractions.

 

HEFA production

Oils and fats are hydrotreated, deoxygenated, and cracked into hydrocarbons suitable for jet fuel blending.

 

For FT chemistry, see Fischer-Tropsch synthesis.

What fuel products come from FT and HEFA?

Both pathways produce synthetic paraffinic kerosene suitable for blending into aviation fuel.

FT pathway

Produces Fischer-Tropsch Synthetic Paraffinic Kerosene (FT-SPK)

 

HEFA pathway

Produces HEFA-SPK

 

Both are approved under ASTM International D7566.

 

For FT fuel details, see Fischer-Tropsch synthetic paraffinic kerosene.

How do FT and HEFA differ in feedstock scalability?

Feedstock availability often shapes where each pathway can expand.

HEFA

 

Depends on available waste oils and fats, which can be limited by competing demand.

 

FT

Can use a wider range of carbon-containing feedstocks once converted into syngas.

 

This means regional feedstock availability strongly influences pathway selection.

How do FT and HEFA differ in plant design?

FT and HEFA plants have different front-end processing requirements.

FT plants include:

  • Feedstock conversion to syngas
  • Gas cleanup
  • Fischer-Tropsch synthesis
  • Product upgrading

 

HEFA plants include:

  • Oil pretreatment
  • Hydrotreating
  • Hydrocracking
  • Fractionation

 

Front-end processing requirements directly affect plant complexity and integration strategy.

Are FT and HEFA both approved SAF pathways?

Yes. Both FT-SPK and HEFA-SPK are approved pathways for sustainable aviation fuel under ASTM standards.

Both fuels:

  • Are blended with conventional jet fuel
  • Meet aviation fuel specifications
  • Require no aircraft modification

 

See ASTM approved SAF pathways for broader pathway context.

Why are FT and HEFA often discussed together?

FT and HEFA are two of the most established SAF pathways and are often compared because they address similar aviation fuel markets through different chemistry.

The comparison usually centers on:

  • Feedstock type
  • Carbon intensity potential
  • Infrastructure fit
  • Scaling pathways

 

Neither pathway replaces the other universally; suitability depends on project conditions.

When is FT preferred versus HEFA?

Pathway selection usually depends on feedstock availability, project economics, and regional infrastructure.

Projects using waste biomass, municipal waste, or syngas-based systems often consider FT.

 

Projects with reliable lipid feedstock supply often consider HEFA.

 

The preferred pathway depends on local conditions rather than a single universal advantage.

Frequently asked questions

Is FT better than HEFA?

They serve different feedstock and project conditions. Suitability depends on available carbon sources and project design.

No. HEFA starts with oils and fats rather than synthesis gas.

FT produces synthetic hydrocarbons that are upgraded into FT-SPK.

Yes. Both pathways are approved and used in commercial SAF development.