Plastic waste pollution of oceans, groundwater and the environment has amounted to 8.3 billion tons of waste over the past 65 years. Only about 12% of this plastic waste has been incinerated and a mere 9% has been recycled. The remaining 79% goes into landfills and oceans.

According to the United Nations, more than 8 million tons of plastic enters oceans each year. If nothing is done to combat the use and disposal of waste plastics by 2050, the oceans will hold more plastic waste than fish, according to the World Economic Forum.

In light of these numbers, Purdue University have introduced a new chemical conversion process that could transform waste plastic into polyolefin waste, a form of plastic that can be used as clean fuel or recycled into other products.

More than 8 million tons of plastic flows into oceans each year. Source: Purdue UniversityResearchers believe more than 90% of polyolefin waste can be converted into pure polymers, naphtha, fuels or monomers. The team is also working with the Purdue Fuel Laboratory of Renewable Energy at the School of Engineering Technology to optimize the conversion process to produce high-quality gasoline or diesel fuels.

“Our strategy is to create a driving force for recycling by converting polyolefin waste into a wide range of valuable products, including polymers, naphtha (a mixture of hydrocarbons), or clean fuels,” said Linda Wang, the Maxine Spencer Nichols Professor in the Davidson School of Chemical Engineering at Purdue University. “Our conversion technology has the potential to boost the profits of the recycling industry and shrink the world’s plastic waste stock.”

The process uses selective extraction and hydrothermal liquefaction. Once the plastic is converted into naphtha, it can be used as a feedstock for other chemicals or further separated into specialty solvents or other products.

Researchers said the clean fuel generated from the process could help satisfy 4% of the annual demand for gasoline or diesel fuels.

“Plastic waste disposal, whether recycled or thrown away, does not mean the end of the story,” Wang said. “These plastics degrade slowly and release toxic microplastics and chemicals into the land and the water. This is a catastrophe, because once these pollutants are in the oceans, they are impossible to retrieve completely.”

The full research can be found in the journal ACS Sustainable Chemistry & Engineering.