On the Potential of Waste Tire Pyrolysis in Carbon Mitigation: A Review

The global accumulation of waste tires (WTs), exceeding 25 million tons annually, presents both environmental challenges and opportunities for sustainable resource recovery. Pyrolysis has emerged as a leading thermochemical technology for WT management, converting rubber waste into valuable products—tire pyrolysis oil (TPO), tire pyrolysis gas (TPG), and recovered carbon black (rCB)—while mitigating greenhouse gas (GHG) emissions. This review systematically evaluates pyrolysis-based carbon reduction mechanisms through three interconnected pathways: (1) material substitution, where TPO displaces fossil diesel (2.7-3.2 kg CO2e/kg) and rCB replaces virgin carbon black (1.8-2.2 kg CO2e/kg); (2) energy self-sufficiency, leveraging TPG’s high calorific value (30-40 MJ/m3) to eliminate 60-100% of external energy demand. A comparative analysis of recent life cycle assessment (LCA) studies shows that optimized pyrolysis systems can effectively reduce CO2 emissions, with emission reduction effects exceeding those of traditional treatment methods such as incineration or landfill. Furthermore, technological innovations such as catalytic upgrading and policy instruments like carbon credit recognition are discussed as enablers for industrial scalability. The study concludes that pyrolysis is not only a feasible waste-to-resource solution but also a strategic component in global decarbonization and circular economy initiatives.