An overview of catalytic pyrolysis of plastic waste over base catalysts

Excessive plastic consumption has enormous environmental consequences, including global climate change, the accumulation of non-biodegradable substances, and the depletion of fossil fuel resources. Accordingly, sustainable treatment of waste plastics must be prioritized to achieve a greener world while generating valuable energy products. Pyrolysis has been proven to be an environmentally friendly strategy for recycling plastic waste. In addition, the employment of catalysts in the pyrolysis process, particularly base catalysts, can improve the quality of the products. Base catalysts are highly selective for the formation of alkenes and aromatic hydrocarbons. In addition, the basicity of the catalyst can influence the pyrolysis products. Catalysts with lower basicity promote the formation of aldehydes and ketones, whereas catalysts with strong basicity can encourage hydrocarbon production. In addition, base catalysts can enhance the quality of pyrolytic oil by decarboxylating acidic compounds. Accordingly, this review focuses on the pyrolysis of plastic waste by employing base catalysts. The correlation between catalyst features and catalytic activity in the pyrolysis of plastic waste was also emphasized. [Display omitted] •Various types of plastic waste in catalytic pyrolysis over base catalysts were discussed.•The base catalyst can improve selectivity for the formation of aromatic hydrocarbons.•Base catalysts are more resistant to coke deposition than acid catalysts in catalytic pyrolysis.•Carbon-supported MgO base catalysts perform more effectively than bulk MgO.