Recycling of Polyvinyl Chloride with Polypropylene Derivative

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Plastic recycling, particularly for polyvinyl chloride (PVC), is a significant environmental challenge.
• Developing efficient methods for upcycling waste plastics like PVC and polypropylene (PP) is crucial for sustainable waste management.

Purpose of the Study:

• To develop a catalytic system for the efficient upcycling of PVC and PP waste plastics.
• To convert PVC into valuable olefins and chlorinated chemicals using a novel catalyst derived from PP.

Main Methods:

• Polypropylene (PP) was converted into carbon nanotubes-capped nickel nanoparticles (Ni/CNTs) by mixing with Ni2O3 powder and high-temperature treatment.
• The synthesized Ni/CNTs catalyst was used to trigger the dechlorination of PVC and chlorination of tetrahydrofuran (THF) under light irradiation.
• The dechlorinated PVC (DPVC) was further processed into alkanes and olefins over the Ni/CNTs catalyst.

Main Results:

• Achieved 96.3% dechlorination efficiency of PVC with 97.9% THF conversion and 93.3% selectivity for 4-chloro-1-butanol under optimal conditions.
• Successfully converted dechlorinated PVC (DPVC) into C1-C4 alkanes (49.1% selectivity) and C2-C4 olefins (50.9% selectivity) using the Ni/CNTs catalyst.
• Demonstrated a high efficiency in upcycling both PVC and PP waste streams.

Conclusions:

• This work introduces a feasible and efficient strategy for the co-upcycling of PVC and PP waste plastics.
• The developed catalytic process shows significant potential for environmentally friendly waste plastic management and resource recovery.