New Reactor Converts Plastic Waste Into Jet Fuel at Potentially Competitive Cost

Researchers have developed a two stage chemical process that converts discarded plastic into fuel suitable for aviation applications.

The system addresses a common problem in plastic recycling. Existing chemical methods can break plastic into smaller molecules, but they often create a broad mixture of products. Separating and refining those materials into a consistent jet fuel can add complexity and cost.

The new approach uses two connected reactors operating at different temperatures. The first breaks plastic into intermediate compounds, while the second converts those materials into a more controlled mixture rich in cycloalkanes.

Cycloalkanes are energy dense hydrocarbons that can support the performance requirements of aviation fuel. The researchers estimate that fuel produced through the process could cost between $1 and $1.80 per kilogram. That range overlaps with conventional jet fuel pricing, although the calculation is based on an early technical and economic analysis rather than commercial production.

Process detail	Reported specification
First reactor temperature	460 degrees Celsius
Second reactor temperature	160 degrees Celsius
Catalyst material	Atomically dispersed ruthenium on cobalt aluminium oxide
Main fuel components	Jet fuel range cycloalkanes
Estimated production cost	$1 to $1.80 per kilogram
Current development stage	Laboratory scale
Next development goals	Larger catalyst production and continuous processing

Two reactors improve control over the final fuel

Plastic waste first enters a reactor operating at 460 degrees Celsius. At this temperature, the long polymer chains are broken into smaller intermediate molecules through a process involving heat and hydrogen.

Those compounds then move into a second reactor operating at 160 degrees Celsius. This stage uses a specialised catalyst containing isolated ruthenium atoms supported by cobalt aluminium oxide.

The catalyst helps convert the intermediate material into saturated ring shaped hydrocarbons. During testing, it delivered hydrogenation activity more than 100 times higher than a conventional commercial ruthenium catalyst for a key reaction.

Using isolated metal atoms can make more of the expensive catalyst material available for chemical reactions. It can also influence which molecules are produced, improving selectivity and reducing unwanted byproducts.

Better selectivity is important because aviation fuel must meet strict requirements for energy density, stability, freezing behaviour and combustion performance. A process that produces a narrower and more useful group of hydrocarbons may require less refining than methods that create a poorly controlled mixture.

The projected cost is promising but remains unproven at scale

The researchers estimate a minimum selling price of approximately $1 to $1.80 per kilogram. Conventional fossil based jet fuel can cost around $1 to $1.30 per kilogram, although prices vary with crude oil markets, regional supply and refinery conditions.

The upper end of the recycled fuel estimate remains more expensive than conventional fuel. However, it may compare favourably with some sustainable aviation fuels that depend on costly oils, agricultural products or specially prepared biomass.

The calculation will need to be tested through larger facilities. Commercial costs will depend on the price and condition of plastic waste, hydrogen consumption, catalyst life, energy use and the expense of separating unsuitable materials.

The environmental benefits also require a complete life cycle assessment. Turning waste plastic into fuel could reduce landfill use and replace some newly extracted fossil resources, but burning the final product will still release carbon dioxide.

The climate impact will depend partly on how the hydrogen and process heat are produced. Renewable electricity and low emission hydrogen could improve the overall result, while fossil based energy would reduce the advantage.

Industrial production will require substantial further work

The process has so far been demonstrated at laboratory scale. The team’s next goals include producing the catalyst in kilogram quantities and developing a continuous feeding system.

Continuous operation is essential for commercial fuel production because an industrial plant must process material steadily rather than in small experimental batches. Engineers will also need to determine how the catalyst performs after long periods of use and whether contaminants in real plastic waste reduce its effectiveness.

Mixed waste presents another challenge. Packaging can contain several polymers, dyes, additives, food residue and other materials. A commercial facility may require sorting and preparation before the plastic reaches the reactors.

Despite these uncertainties, the research offers a useful direction for two difficult problems. Plastic waste continues to accumulate, while long distance aviation remains difficult to electrify because aircraft require lightweight fuels with high energy density.

The process is not ready to supply airports, but its controlled fuel production and projected cost make it a promising candidate for further development.