- Research converts agricultural residues into high-performance biodegradable polymer
- Electric-catalysis route offers lower-energy path to next-generation packaging materials
A research team at Westlake University in Hanghzou has developed a catalytic process that converts agricultural waste such as crop straw into a plant-based plastic alternative, a potential step toward reducing reliance on petroleum-derived materials.
The work, published in Angewandte Chemie International Edition, a German academic journal on applied chemistry, was led by Professor Sun Licheng’s laboratory at the university’s Center of Artificial Photosynthesis for Solar Fuels, with contributions from researchers including assistant researcher Cao Xing and doctoral student Li Jiayi.
The process produces polyethylene furanoate, or PEF, a bio-based polymer positioned as a substitute for polyethylene terephthalate (PET), the world’s most widely used plastic.
PET production totals nearly 100 million tons annually, commonly used in beverage bottles and packaging.
Unlike PET, which depends on fossil fuel feedstocks and is difficult to recycle at scale, PEF is derived from plant-based raw materials. Its key precursor, HMF, or 5-Hydroxymethylfurfural, is an organic compound formed in heated foods.
It can be extracted from crops such as corn, sugarcane and agricultural residues including straw—an abundant resource in China, one of the world’s largest producers of crop waste.
Beyond feedstock advantages, the researchers said PEF also offers performance improvements. It has significantly stronger gas barrier properties than PET, which could extend food shelf life and reduce the need for preservatives.
China has already approved PEF for food-contact applications following a safety review earlier this year.
At the core of the process is a catalytic conversion of HMF into FDCA, traditionally carried out using high-temperature, high-pressure thermal methods that are energy intensive.
An electrochemical approach
The Westlake team instead used an electrochemical approach, driving the reaction using electricity under ambient conditions, with the potential to be powered by renewable sources such as wind and solar.
“We want both a green product and a green process,” said researcher Cao.
The key breakthrough lies in a cobalt molybdate catalyst developed after screening more than a dozen candidate materials. Under electrochemical conditions, the system achieved near-99% yield and electron efficiency in converting HMF to FDCA.
The researchers also found that the spin state of cobalt atoms plays a role in reaction efficiency, with higher spin states improving catalytic performance.
“We not only built a better catalyst, we can also explain why it works,” said Professor Sun.
While industrial-scale deployment remains in development, upstream production capacity is already emerging.
A one-million-tonne-class HMF production facility in Zhejiang was structurally completed in December, laying groundwork for potential scaling of plant-based plastics.
Sun said the long-term aim is to shift agricultural waste away from open burning and toward industrial reuse, with renewable electricity providing process energy and hydrogen emerging as a by-product.
