Plasma-Enabled Process with Single-Atom Catalysts for Sustainable Plastic Waste Transformation

Area of Science:

• Materials Science and Engineering
• Chemical Engineering
• Environmental Science

Background:

• Growing plastic waste necessitates innovative recycling solutions.
• Conventional thermal pyrolysis faces limitations in efficiency and product yield.
• Plasma-enabled processes offer potential for advanced material conversion.

Purpose of the Study:

• To develop a plasma-enabled strategy for rapid plastic waste decomposition.
• To convert diverse plastic wastes into high-value carbon nanomaterials and hydrogen.
• To investigate the enhancement of hydrogen production using single-atom catalysts.

Main Methods:

• Utilized a catalyst-free plasma-enabled strategy for plastic waste breakdown.
• Investigated the synergistic effect of plasma pyrolysis coupled with thermal catalytic processes.
• Employed atomically dispersed M/CeO2 (M=Fe, Co, Ni) catalysts for enhanced hydrogen production.
• Combined experimental and computational approaches to understand catalytic mechanisms.

Main Results:

• Achieved significantly higher hydrogen (H2) yield and selectivity compared to conventional thermal pyrolysis.
• Demonstrated superior energy yield for H2 production with the catalyst-free plasma approach.
• Identified 1 wt% Co/CeO2 as highly effective, yielding 64.4% of theoretical H2 production.
• Showcased comparable H2 yield using single-atom Fe catalysts as with Fe particles, reducing catalyst loading.

Conclusions:

• The developed plasma-enabled process offers an efficient and cost-effective method for chemical plastic recycling.
• Atomically dispersed catalysts significantly enhance hydrogen production in the integrated plasma-thermal process.
• This approach provides a viable strategy for converting mixed and contaminated plastic waste into valuable products, supporting a circular plastic economy.