# Chemical recycling of polyolefins: a closed-loop cycle of waste to olefins

## TL;DR

This paper explores chemical recycling of polyolefin plastics to convert waste into valuable olefins, aiming for a sustainable and closed-loop recycling process.

## Contribution

The paper provides a comprehensive overview of polyolefin chemical recycling, emphasizing pretreatment, pyrolysis, and life cycle assessment.

## Key findings

- Chemical recycling of polyolefins can convert waste into olefins through processes like pyrolysis.
- Pretreatment of plastic waste is essential for efficient chemical recycling.
- Life cycle assessment is crucial for evaluating the sustainability of chemical recycling.

## Abstract

The unsuitable disposal of plastic wastes has caused serious environmental pollution, and finding a green manner to address this problem has aroused wide concern. Plastic wastes, especially polyolefin wastes, are rich in carbon and hydrogen, and chemical recycling shows distinct advantages in their conversion into olefins and realizes a closed-loop cycling of plastic wastes. Plastic wastes should be labeled before disposal. The necessity for, and methods of, pretreatment are introduced in this paper and the whole recycling process of polyolefin wastes is also summarized. As the core technology pyrolysis, including thermal, catalytic and solvolysis processes, is introduced in detail due to its potential for future development. We also briefly describe the feasible strategies of pyrolytic oil refining and life cycle assessment of the chemical recycling process. In addition, suggestions and perspectives concerning the industrial improvement of polyolefin chemical recycling are proposed.

This paper gives an overview of the whole chemical recycling process of polyolefin wastes, including the pretreatment of feedstocks, chemical recovery, product refining to olefins, and LCA analysis of chemical recycling.