Protonera, a UK-based plastic recycling company founded in 2023, develops an innovative technology that transforms waste plastics into green hydrogen and other value-added products. This technology aims to address the challenges of plastic recycling, which is often unprofitable and difficult for low-grade waste.
Challenges: waste plastic recycling
Waste waste has become a pressing environmental issue in our modern society, threatening both ecosystems and human health. The global production of synthetic plastics reaches millions of tons annually to meet consumer demands, yet recycling efforts fall significantly short. Less than 20% of plastics are recycled worldwide, with approximately 50% ending up in landfills and 19% being incinerated for energy recovery.
The problem of landfill is exacerbated by micro- and nano-plastics, which have become pervasive pollutants in terrestrial and marine environments. These microscopic plastic particles accumulate in soil and water bodies, presenting unique recycling challenges due to their low concentrations and tiny sizes. As they move up the food chain, they pose risks to biodiversity and potentially human health through contaminated food sources.
Plastic recycling offers a multifaceted approach to address the growing challenges of plastic waste.
Protonera Technology
Mechanical recycling is the most widely used method for plastic recycling, but it only processes about 16% of waste plastic. This process is well-established for common plastics such as PE, PP, and PET, and involves several key steps:
- Collection of plastic waste from recycling centers
- Sorting of waste plastic in plastic recovery facilities
- Thorough cleaning of sorted plastics
- Shredding clean plastics into small flakes or pellets
- Melting and extruding plastic flakes to form new products or raw materials
Despite its widespread use, mechanical recycling faces several challenges:
- Sorting difficulties: The wide variety of plastic types and grades makes efficient sorting challenging.
- Mixed and composite materials: These are particularly difficult to separate mechanically.
- Quality issues: Mechanically recycled plastics often have lower quality compared to virgin plastics, limiting their applications and market value.
- Cost concerns: In some cases, the cost of mechanical recycling can exceed that of producing new plastics.
Chemical recycling methods are less commonly used, accounting for less than 3% of waste plastic recycling. These methods include:
- Pyrolysis: this process involves heating plastics in an oxygen-free environment to break them down into smaller molecules.
- Solvolysis: this method uses solvents to break down polymers.
- Enzymolysis: this technique employs enzymes to depolymerize targeted polymers.
While chemical recycling methods offer potential advantages in dealing with mixed and contaminated plastics, their current low utilization rate indicates that significant development and scaling are still needed to make them more widely applicable in the recycling industry.
Protonera has developed an innovative technology that combines enzymatic degradation and photocatalytic reforming to transform waste plastics into hydrogen (Hâ‚‚) and valuable organic compounds. This process involves two key steps:
- Enzymatic depolymerization: specific enzymes are used to break down polyester plastics into their constituent monomers..
- Photocatalytic reforming: the monomers obtained from the enzymatic process are then subjected to photo-oxidation, which utilizes light energy to catalyze the conversion of these monomers intoHâ‚‚ or syngas and high-value organic chemicals.
Protonera’s approach  enables the processing of waste plastics into valuable organic compounds, creating additional economic incentives for plastic waste recycling. The production of hydrogen or syngas provides a clean energy carrier, aligning with the growing demand for sustainable fuel sources.
How Protonera converts plastic into Hâ‚‚Â and organic chemicals
The diagram below illustrates Protonera's system for converting polyester into hydrogen gas and other valuable chemicals.