US-China Team Converts PVC and Mixed Plastic Waste Into Petrol at Low Temperatures

Laboratory Tests Reach Up to 99 Percent Conversion

Scientists from the United States and China have developed a process that turns difficult plastic waste into hydrocarbons in the petrol range while recovering hydrochloric acid. Laboratory tests achieved 95 percent conversion for soft polyvinyl chloride (PVC) pipes and 99 percent for rigid PVC pipes and wires at 30°C. A mixture containing PVC and other common plastics reached 96 percent conversion at 80°C.

The research brings together scientists from Pacific Northwest National Laboratory, Columbia University, the Technical University of Munich and East China Normal University. Their approach combines two operations that usually require separate treatment: removing chlorine from PVC and converting the remaining material into useful fuel molecules.

The temperature depends on the waste being processed. PVC can be treated around room temperature, while mixed polyolefin waste, including polyethylene and polypropylene, requires 80°C. The process operates at ambient pressure, meaning the pressure of the surrounding air.

Those conditions offer a potential advantage over conventional technologies such as pyrolysis and gasification, which generally require high temperatures, substantial energy and multiple processing stages. The researchers describe a simpler route that could reduce equipment requirements and make difficult waste more attractive to collect.

As of August 28, 2025, the central achievement is a laboratory process with high conversion rates across several tested materials. Turning it into a widely used industrial operation will require further research and investment, including tests of consistent performance with waste containing different additives and contaminants.

Why PVC Makes Recycling Difficult

PVC is widely used in pipes, window frames and cables. Its chlorine content makes it especially troublesome when mixed with other discarded plastics. Conventional treatment usually needs a separate step to remove that chlorine, helping prevent hazardous compounds from forming during later processing.

The new method combines chlorine removal, known as dechlorination, with the conversion of the plastic into fuel. It produces hydrocarbons in the fuel range without chlorine and recovers hydrochloric acid as a second useful product.

The tests on soft and rigid PVC matter because discarded plastic arrives in different forms. Soft pipes reached 95 percent conversion, while rigid pipes and wires reached 99 percent, all at 30°C. The results show that the process worked across those tested PVC products.

Mixed waste presents another challenge because different plastics must be processed together. When PVC was combined with polyolefin waste, the process maintained a conversion rate of 96 percent at 80°C. That result points to a possible route for handling mixed and contaminated material that is difficult to recycle through established methods.

How Plastic Becomes Fuel in One Step

The process uses light isoalkanes, hydrocarbons that are byproducts of refinery operations, to help convert plastic waste into smaller molecules. Hydrocarbons are compounds made from hydrogen and carbon, the same basic elements found in petrol and many plastics.

Plastic consists of long molecular chains. Converting it into fuel requires breaking those chains into smaller pieces and controlling which molecules form. In this approach, the reaction between the waste and light isoalkanes yields hydrocarbons in the gasoline range, while PVC supplies the chlorine recovered as hydrochloric acid.

Catalysts play a central role in controlling the breakdown and recombination of the plastic molecules. A catalyst speeds up a chemical reaction without being consumed by it. Here, catalysts help direct the process toward valuable fuels at temperatures far below those normally associated with conventional plastic conversion.

Polyolefins such as polyethylene and polypropylene account for most plastic waste. Their strong bonds between carbon atoms make them difficult to break apart. The ability to work on these bonds at lower temperatures is one reason the research could reduce energy use and operating costs.

The single stage approach also reduces the number of separate processing operations. Instead of removing chlorine first and converting the remaining plastic later, the method combines those tasks within the same treatment. That simplicity is part of its appeal for possible industrial use.

Hydrochloric Acid Adds a Second Product

Hydrochloric acid gives the process another potential source of value alongside fuel. The chemical is used in water treatment, metal processing, pharmaceuticals and food production, creating possible outlets for material recovered from PVC waste.

The acid requires safe management. It can be neutralized safely, while recovered acid can also be reused in industrial applications. Handling it properly would remain part of operating any facility using this process.

Recovering a useful chemical changes the economic calculation for difficult waste. A processor could obtain both fuel and an industrial chemical from material that might otherwise be discarded, creating more than one potential revenue stream.

The research team presents this recovery as part of a circular economy, in which materials retain value and return to industrial supply chains. The practical aim is to make collection and processing worthwhile, including for PVC that creates problems in other recycling systems.

Making Collection Worth More Than Disposal

Johannes Lercher, director of the Institute for Integrated Catalysis at Pacific Northwest National Laboratory and a coauthor of related studies, described the economic change needed to deal with persistent plastic waste:

To solve the problem of persistent waste plastic, we need to reach a critical point where it makes more sense to collect it and return it to use than to treat it as disposable.

Lercher's point connects the chemistry to the everyday decisions that determine where rubbish goes. A useful process needs waste to reach it. Producing valuable fuel and chemicals could give businesses a stronger reason to recover plastic rather than send it for disposal.

Lower temperatures, fewer processing stages and reduced equipment needs could help that calculation. The process is designed with industrial scale use in mind, and its developers see potential for existing facilities to integrate plastic conversion without major infrastructure changes.

Commercial adoption still requires work beyond the laboratory. Consistent treatment of changing waste mixtures, investment in larger operations and the management of recovered chemicals all form part of that transition.

How It Compares With Other Recycling Methods

Pyrolysis and gasification are established routes for converting waste into other products, but they generally rely on high temperatures and substantial energy. Mixed or contaminated plastics can complicate treatment, particularly when PVC introduces chlorine and the risk of toxic emissions if it is handled improperly.

The new process seeks to address those problems through lower temperatures and combined treatment. Its ability to process PVC alongside polyolefins is especially relevant to waste streams containing several types of plastic.

Mechanical recycling remains important. It shreds and remelts plastic so the material can be used again, but contamination and declining material quality limit what it can handle. Chemical recycling changes the molecules themselves, offering another route for material that is otherwise destined for landfill or incineration.

Mixed waste and packaging made from multiple layers are among the materials that chemical recycling approaches aim to address. The practical choice depends on the material involved and the treatment it requires. For the new process, the reported laboratory results focus on PVC products and mixtures containing polyolefins.

Other Researchers Target New Plastic and Chemicals

Researchers at the University of California, Berkeley, have developed a different catalytic process that vaporizes plastic bags and bottles into hydrocarbon building blocks for new plastics. It works at relatively low temperatures and can handle mixtures of polyethylene and polypropylene.

Those two plastics make up about two thirds of plastic waste discarded by consumers worldwide. A method that can process them together therefore addresses a large share of the waste stream, while pursuing a different output from the petrol produced by the US-China team's approach.

Other research uses microwaves to heat plastics in the presence of catalysts such as ZSM-5 or carbon felt. These methods can selectively produce benzene, toluene, ethylbenzene and xylene, collectively known as BTEX, or light olefins such as ethylene and propylene. Selectivity describes how strongly a process favors particular products.

Induction heating with carbon catalysts containing no metal has also shown promise for converting waste plastic into olefins and aromatics with high efficiency and low energy consumption. These are other groups of chemicals that researchers can target when breaking down plastic.

Many alternative technologies still require high temperatures or several stages, or face difficulties with mixed and contaminated waste. The distinctive feature of the US-China approach is its combination of PVC treatment and fuel production at low temperatures.

The Scale of the Waste Problem

Global plastic production has surpassed 10 billion tonnes, while only about 9 percent of all plastic ever produced has been recycled. Much of the remainder has accumulated in landfills or the natural environment, or has been incinerated.

Discarded plastic pollutes waterways and oceans as well as land. Incineration and other stages of plastic use and disposal also contribute to greenhouse gas emissions. These pressures help explain the search for methods that recover value from materials conventional systems struggle to accept.

The new process could reduce reliance on fossil fuels by recovering fuel from waste plastic. Its low operating temperatures also offer a potential way to reduce the energy required for conversion compared with conventional high temperature treatment.

Fuel production has a different outcome from making new plastic. When fuel is burned, its carbon is eventually released as carbon dioxide. Some environmental advocates therefore caution that converting plastic into fuel still carries a climate cost, even where it offers a preferable destination to landfilling or incineration.

A broader strategy would combine recovery technologies with efforts to reduce plastic production, improve product design for recycling and promote renewable materials. Those measures address how much waste is created, while conversion technologies deal with material that has already been discarded.

What Industrial Adoption Would Require

Industrial waste supplies contain changing combinations of plastics, additives and contaminants. Further research must establish how consistently the process performs across those mixtures as operations expand beyond laboratory conditions.

Investment is another requirement. The attraction of fewer stages and less equipment needs to be carried into larger facilities capable of handling sustained flows of waste. The researchers see a route to industrial deployment, but scaling the process remains a task ahead.

Regulatory approval and public acceptance will also matter. Potential emissions and the safe handling of hydrochloric acid are among the concerns that would need attention as the technology moves toward wider use.

The economic case rests on several connected parts: the cost of collecting waste, the energy and equipment required to process it, and the value of the resulting fuel and chemicals. The new chemistry seeks to improve that balance by working at lower temperatures and recovering two useful products.

A Wider Push to Keep Materials in Use

Projects in the United Kingdom are exploring ways to convert plastic waste into hydrogen or oil. Around the world, researchers are developing new catalysts and reactor designs to improve conversion efficiency and control the products that emerge.

Microwave heating, induction heating and continuous processing systems are among the approaches contributing to that work. Together, these efforts seek more sustainable and economically workable ways to recover materials from discarded plastic.

The circular economy aims to keep materials in use for as long as possible, recover their value and reduce waste. The US-China process contributes to that goal by turning difficult plastic streams into fuel and industrial chemicals that can return to supply chains.

Its immediate contribution is a set of laboratory results showing high conversion at low temperatures, including for chlorine containing PVC. Continued research, investment and policy support would be needed to turn that achievement into a widely used waste management option.

Key Points

• A team involving Pacific Northwest National Laboratory, Columbia University, the Technical University of Munich and East China Normal University has combined PVC dechlorination and fuel conversion in one stage.
• Laboratory conversion reached 95 percent for soft PVC pipes and 99 percent for rigid PVC pipes and wires at 30°C.
• A mixture containing PVC and polyolefin waste reached 96 percent conversion at 80°C.
• The process operates at ambient pressure and uses light isoalkanes to help produce hydrocarbons in the petrol range while recovering hydrochloric acid.
• Lower temperatures and fewer processing stages could reduce energy use, equipment needs and operating costs.
• Further research and investment are needed for industrial adoption, including consistent treatment of varied waste and safe chemical handling.
• Burning the resulting fuel releases carbon dioxide, making plastic reduction, better product design and other recycling approaches part of the wider response.