A green landscape with an airplane and chemical icons symbolizing Net Zero and SAF

Sustainable Aviation Fuel (SAF) – Driving the future of clean air travel

Low-carbon aviation is no longer a vision — it’s becoming reality. With advanced SAF technologies and renewable jet fuel solutions, we enable the transition to cleaner skies and a more sustainable future for air travel.

Learn how we support SAF innovation through high throughput catalyst testing and process optimization — helping our partners develop next-generation fuels that reduce emissions and meet global climate goals. 

What is Sustainable Aviation Fuel (SAF)?

Sustainable Aviation Fuel (SAF) is an alternative jet fuel certified under ASTM D7566 standards, ensuring full compatibility with existing aircraft engines and infrastructure. By blending traditional kerosene with SAF, airlines can significantly lower their carbon footprint and contribute to global climate goals.

SAF is produced from renewable feedstocks such as biomass, waste oils, or captured CO₂, making it a cornerstone of green aviation fuel strategies.

Chemical composition of SAF

SAF primarily consists of hydrocarbons similar to conventional jet fuel — paraffins, iso-paraffins, cyclo-paraffins, and aromatics — but derived from sustainable sources. Depending on the production pathway (e.g., HEFA, Fischer-Tropsch, Alcohol-to-Jet), SAF includes:

  • Normal and iso-paraffins for high energy density
  • Cyclo-paraffins and aromatics for material compatibility
  • Minimal sulfur and nitrogen compounds, reducing emissions

By replacing fossil-based kerosene with SAF, airlines can meet stringent performance and safety standards while advancing toward low-carbon aviation.

Overview SAF production pathways

Map with 11 ASTM-approved SAF production pathways
11 ASTM-approved SAF production pathways

There are currently 11 ASTM‑approved pathways for producing Sustainable Aviation Fuel (SAF) under ASTM D7566, comprising 8 standalone processes and 3 co‑processing options. All approved pathways qualify SAF as a drop‑in fuel, allowing blending with conventional Jet A up to the certified limit (typically 50% for most standalone routes).

Among these pathways, HEFA‑SPK is currently the only route fully commercialized at industrial scale, while others such as FT‑SPK and ATJ‑SPK are in pilot or demonstration phases. One additional route, Methanol‑to‑Jet (MTJ), is undergoing the ASTM fast‑track approval process. The co‑processing options enable lower SAF blend volumes by integrating renewable intermediates into existing crude‑oil refinery units.

Across all pathways, continuous catalyst development and process optimization remain critical to reduce costs, improve efficiency, and enable large‑scale SAF deployment.

Quick facts: SAF production pathways

  • ASTM-approved SAF pathways: 8 standalone + 3 co-processing options
  • Blend limit: Up to 50% for most standalone routes
  • Fully commercialized: HEFA-SPK (Hydroprocessed Esters and Fatty Acids)
  • Pilot scale: FT-SPK, FT-SKA, ATJ-SPK
  • Under development: SIP, CHJ, HC-HEFA-SPK
  • Emerging: Methanol-to-Jet (MTJ) – fast-track ASTM approval
  • Co-processing: Vegetable oils & intermediates in crude oil refineries (pathway‑specific blend limits 5–10%)
  • Key challenge: Catalyst innovation and process optimization for for cost-effective scale-up

Abbreviations

HEFA-SPK: Hydroprocessed Esters and Fatty Acids – Synthetic Paraffinic Kerosene
FT-SPK: Fischer–Tropsch Synthetic Paraffinic Kerosene
FT-SKA: Fischer–Tropsch Synthetic Kerosene with Aromatics
ATJ-SPK: Alcohol-to-Jet – Synthetic Paraffinic Kerosene
SIP: Synthesized Iso-Paraffins
CHJ: Catalytic Hydrothermolysis Jet
HC-HEFA-SPK: Catalytic Hydrothermolysis Jet

How hte supports SAF process development

With over 25 years of experience, we have built a robust technology platform to accelerate Sustainable Aviation Fuel (SAF) innovation. Our expertise covers all catalytic steps required across ASTM-approved pathways for renewable jet fuel, helping the industry move toward low-carbon aviation and net zero air travel.

Each star in the process map highlights a step where hte provides proven solutions — from catalyst synthesis to scale-up, kinetic studies, and competitive catalyst benchmarking. Our our integrated R&D workflows deliver reliable, high-quality data with closed mass balances, enabling cost-effective process development.

Publication

Accelerate SAF R&D with high throughput catalyst testing

An icon of an airplane

Our latest overview publication summarizes our current SAF activities, including key topics such as Fischer-Tropsch synthesis, oligomerization, and hydrotreating of vegetable oils. It highlights how our technology platform supports process development for Sustainable Aviation Fuel.

Explore our customer success stories and press releases in the Knowledge Hub below to see how hte is decarbonizing air travel through advanced catalyst testing and process optimization. For syngas-related topics, please visit our carbon management focus page.

Fabian Schneider
Fabian Schneider

Director Business Development and Marketing

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