OXCCU, a UK cleantech startup founded in 2021, develops highly efficient and inexpensive iron-based catalysts for direct conversion of recycled carbon dioxide and green hydrogen into jet fuels and plastics. OXCCU’s technology provides an attractive route not only to reduce carbon dioxide emissions, but also to produce carbon-neutral jet fuels and plastics.
Challenges: carbon neutral jet fuel
About 3% of global carbon dioxide emissions come from the aviation industry, and that number is going up. The industry has pledged to achieve net-zero emissions by 2050. Carbon-neutral jet fuels, which don’t add to greenhouse gas emissions, are being looked into by the aviation industry. The carbon-neutral jet fuels include sustainable aviation fuels (SAF) and synthetic fuels.
Sustainable aviation fuel (SAF) is a type of fuel that has similar properties to conventional jet fuel but with a smaller carbon footprint. Compared to conventional jet fuel, it can reduce greenhouse gas emissions by up to 94%. SAF is made from green hydrogen and non-petroleum feedstocks, including forestry and agricultural waste, used cooking oil, and carbon captured from the air. SAF is a “drop-in” fuel, which means it can be blended with or replace traditional jet fuel without requiring infrastructure or equipment modifications.
Synthetic fuels are manufactured using green hydrogen and carbon dioxide or carbon monoxide. The process involves adding carbon to hydrogen to produce a liquid fuel, which can be gasoline, diesel, gas, or even kerosene. Carbon dioxide can be recycled from industrial processes or even captured from the air. Synthetic fuels are also a “drop-in” fuel.
OXCCU has developed inexpensive, highly efficient iron-based catalysts for the direct and efficient conversion of recycled carbon dioxide (CO₂) and green hydrogen (H₂) to jet fuel range hydrocarbons. The iron-based catalysts are prepared using a facile, energy-saving, and cost-effective one-pot synthesis method. The size of the produced catalyst particles is around 14 nm. After activation, the catalysts show a high carbon dioxide hydrogenation activity and a high selectivity of jet fuel range hydrocarbons.
OXCCU produces the iron-based catalysts using an energy-efficient and economically viable Organic Combustion Method (OCM). This approach can produce crystalline metal oxide powder catalysts that are homogeneous, ultrafine, and of high-purity.
In this method, different metal precursors and cation-complexation organic molecules are mixed in one pot to yield a homogeneous aqueous redox solution. This initial mixture was stirred and heated at 50 ºC for 1–2 h to produce a slurry. This slurry was then ignited at 350 ºC in air for 4 h to produce a carbon-free nanopowder. The catalyst precursor is almost fully converted to χ-Fe₅C₂.
The obtained catalyst particle has a size of around 14 nm and needs to be activated during the first hours of the catalytic reaction. This activation process regenerates Fe₃O₄ phase in the catalyst nanoparticle. The activated catalyst shows a high CO₂ hydrogenation activity and high jet fuel range selectivity.
How OXCCU converts CO₂ to jet fuel
The activated catalyst has two catalytically active iron phases, Fe₃O₄ and χ-Fe₅C₂, operate in tandem. This is the key to the high carbon dioxide hydrogenation activity and high jet fuel range selectivity.
The active Fe₃O₄ phase catalyzes the reverse water gas shift (RWGS) reaction, which converts CO₂ to CO:
CO₂ + H₂ → CO + H₂
The active χ-Fe₅C₂ phase catalyzes the hydrogenation of CO through the Fischer-Tropsch process:
CO + H₂ → CₙHₘ + H₂O
The diagram below depicts the synthesis of jet fuels via CO₂ hydrogenation. The RWGS reaction initially takes place on the catalytically active sites of Fe₃O₄, while subsequent FTS reactions occur on catalytically active sites of χ-Fe₅C₂.
Particularly, the Fe–Mn–K catalyst has a high selectivity for jet fuel range C₈–C₁₆ hydrocarbons as liquid products, which account 50% of all produced hydrocarbons. The yield of jet fuel range hydrocarbons is 17% with a CO₂ conversion of 38%.
OXCCU converts CO₂ to PGA plastic
OXCCU also uses its novel catalyst to convert CO₂ to glycolic acid, which is used in the synthesis of polyglycolic acid (PGA) via polycondensation or ring-opening polymerization.
PGA is a polymer with unique properties, including high gas barrier properties, high tensile strength, high resistance to common organic solvents, high heat distortion temperature, and high stiffness. PGA has many applications, such as high gas barrier packaging, masking or etching agents, and films and sheets that require high-strength materials. PGA is a fully biodegradable and compostable polymer that degrades rapidly.
PGA is currently produced using fossil fuels. The technology of OXCCU can reduce the use of fossil fuels and mitigate carbon emissions.
- GB202208467D0 Catalyst composition, methods for its production and use thereof
OXCCU Technology Applications
OXCCU’s technology uses recycled CO₂ captured from the air and industrial exhaust. This avoids the costly underground sequestration of CO₂.
Green hydrogen application
OXCCU’s technology also uses green hydrogen from suppliers who produce hydrogen with renewable energy.
Carbon-neutral jet fuel
OXCCU produces carbon-neutral jet fuels from recycled CO₂ and green hydrogen. This helps the aviation industry reduce carbon emissions.
Carbon-negative PGA polymer
OXCCU makes carbon-negative polyglycolic acid (PGA) from recycled CO₂. This process avoids the use of fossil fuels and reduces CO₂ emissions.
OXCCU is scaling up its production of catalysts and designing its own modular, industrial reactor to produce carbon-neutral jet fuels and carbon-negative PGA plastics.
OXCCU has raised a total of $22.7M in funding over a Series A round raised on Jun 7, 2023.
OXCCU is funded by 10 investors:
- Clean Energy Ventures
- Doral Energy-Tech Ventures
- United Airlines Ventures
- Braavos Investment Advisers
- University of Oxford
- Aramco Ventures
- Eni Next
- Kiko Ventures
- TechEnergy Ventures
Andrew Symes is CEO.
OXCCU Board Member and Advisor
Amrit Jalan is Board Member.