Researchers in the United States have developed a new aluminium-based chemical recycling process that converts plastic waste into fuel-range hydrocarbons at significantly lower temperatures than conventional recycling methods, potentially offering a more energy-efficient approach to managing global plastic pollution.

The technology, developed by scientists at Oak Ridge National Laboratory, uses a molten salt solution containing aluminium chloride to break down polyethylene, one of the world’s most widely used plastics, into liquid hydrocarbons suitable for fuel applications.

The research represents part of a broader global effort to improve chemical recycling technologies as governments and industries face increasing pressure to reduce plastic waste entering landfills, incinerators and natural ecosystems.

According to details released by the research team, the molten aluminium salt serves both as the reaction medium and as the active chemical agent, removing the need for additional catalysts, hydrogen inputs or organic solvents commonly used in other plastic-to-fuel conversion systems.

The process operates at temperatures below 200 degrees Celsius, substantially lower than traditional pyrolysis-based recycling technologies that typically require temperatures between 450 and 500 degrees Celsius. Researchers said the lower operating temperature could reduce energy consumption and improve the economic feasibility of large-scale deployment.

Approximately 60% of the resulting output consists of hydrocarbons within the gasoline fuel range, according to the study. These products could potentially be used in transportation fuels or industrial chemical applications following further processing and refinement.

Polyethylene, the target material used in the experiment, is among the most common plastics globally and is widely used in packaging films, shopping bags, containers and consumer products. Its widespread use has made it a major contributor to global plastic waste streams.

Chemical recycling technologies such as the molten-salt approach differ from conventional mechanical recycling systems, which typically involve sorting, cleaning and remelting plastics for reuse. Mechanical recycling often faces limitations because repeated processing can degrade material quality and because many mixed or contaminated plastics cannot be efficiently recycled through conventional systems.

The Oak Ridge process instead breaks polymer chains into smaller hydrocarbon molecules, transforming waste plastics into chemical feedstocks or fuel products rather than reproducing new plastic material directly.Researchers used neutron scattering and spectroscopy techniques to observe how polymer chains decomposed during the reaction process.

According to the study, these analytical methods helped scientists better understand the chemical mechanisms involved and optimise the breakdown process.The aluminium chloride molten salt system also avoids dependence on expensive catalysts frequently used in advanced chemical recycling systems.

Many competing technologies rely on rare or precious metals to accelerate polymer decomposition, increasing operational costs and creating additional supply-chain constraints.Industry analysts say reducing catalyst requirements could improve scalability if the process proves commercially viable at industrial scale.However, researchers acknowledged that several technical challenges remain before the technology can move toward widespread commercial adoption.

One of the principal obstacles involves the moisture sensitivity of the molten salt mixture. Exposure to water can interfere with reaction efficiency and alter the behaviour of the chemical system, creating operational difficulties for industrial facilities.

The report noted that further work is needed to improve long-term system durability, process stability and industrial safety before large-scale commercialisation becomes practical.Plastic waste remains one of the fastest-growing environmental challenges worldwide.

According to estimates from international environmental agencies, hundreds of millions of tonnes of plastic waste are generated annually, while recycling rates remain comparatively low across many regions.Most plastic recycling today relies on mechanical systems that can only process limited categories of plastic waste efficiently.

Complex, contaminated or multi-layered plastics often remain difficult to recycle economically and frequently end up in landfills or are incinerated.Advanced recycling technologies, including pyrolysis, solvent-based recovery and catalytic depolymerisation, have gained increased investment attention in recent years as policymakers and manufacturers seek alternatives capable of handling mixed plastic waste streams.

Supporters of chemical recycling argue that these technologies could contribute to a more circular plastics economy by treating plastic waste as an industrial feedstock rather than disposable refuse. Critics, however, have questioned whether some plastic-to-fuel systems merely shift environmental impacts from waste management to fuel combustion emissions.

The Oak Ridge aluminium-salt process enters this broader debate at a time when industries are facing mounting regulatory pressure to improve waste recovery rates and reduce environmental pollution associated with plastics.The findings also highlight the growing intersection between the aluminium sector and sustainability-focused industrial technologies.

Aluminium compounds such as aluminium chloride are increasingly being studied for roles in catalysis, energy storage and chemical processing because of their thermal and reactive properties.

Researchers involved in the project said continued development will focus on improving efficiency, reducing operational sensitivities and evaluating the economic viability of scaling the process for industrial use.