Transforming PVC plastic waste to benzene via hydrothermal treatment in a multi-phase system

Abstract

The upcycling of waste plastic to fuels, chemicals and materials is becoming more and more important, while transforming waste plastic into a single product is challenging although very attractive.

Precise activation of C–C bonds for recycling and upcycling of plastics

“…The challenges associated with plastic upcycling arise not only from the activation of C aliph –C aliph bonds but also from the poisoning and deactivation of active sites caused by the presence of unmanageable chlorine elements in the feedstock, such as polyvinyl chloride (PVC). 127–130 For instance, Pidko et al illustrated through a DFT study that the presence of Cl atoms in polyolefins significantly inhibits the performance of catalysts. The Cl atoms can form stable molecular complexes with the catalyst, thereby increasing the energy barrier for the activation of C–H bonds as the initial step.…”

Low-temperature dechlorination of polyvinyl chloride (PVC) for production of H 2 and carbon materials using liquid metal catalysts

“…Therefore, traditional solid catalysts would provide limited interfacial contact. Nonetheless, processes have been developed using solid absorbents/catalysts to: pre-dechlorinate PVC before subsequent hydrogenation/hydrogenolysis to yield long-chain hydrocarbons (8)(9), upcycle PVC into porous carbon with special physicochemical properties (10-11), produce benzene along with carbon material (12), or selectively synthesize organic chlorides and polyethylene-like molecules (13). However, recovering solid catalysts from solid products can be cumbersome.…”

Upgrading Polyvinyl Chloride by ZnO-Assisted Solvothermal Dehalogenation

“…PVC waste is a promising precursor for high-value carbon materials because high-content sp 2 -C can be obtained during HCl removing. Great efforts have been made in pyrolysis and hydrothermal carbonization of PVC. − However, some issues still need to be addressed. For pyrolysis carbonization, the carbon residue rate of direct pyrolysis is only ∼10 wt %.…”