When it comes to converting solid wastes into syngas/hydrogen and highly valued solid carbon products like carbon nanotubes (CNT), gasification has been proven to be one of the most effective thermochemical conversion methods. In this study, a conceptual production plant design and the co-production of hydrogen and CNT from waste biomass and waste tyre co-gasification were investigated. The integration of these waste materials into a single gasification system aims to maximize resource utilization and minimize environmental impact. The process involves the thermal decomposition of waste biomass and tyres at high temperatures in an oxygen-limited environment, producing syngas (a mixture of hydrogen, carbon monoxide, and other gases) and solid carbon by-products. Water gas shift techniques are employed to enhance the production of hydrogen and to synthesize high-quality carbon nanotubes from the excess CO2 from the process. This process is quite complex and only a few authors have explored CNT production from waste tyre gasification. Key performance indicators such as carbon and energy efficiencies were assessed. The results indicate that the co-production approach can achieve competitive hydrogen production costs while generating valuable CNTs, providing a dual revenue stream. Apart from the limited studies that have explored the LCA of the process, the effect of co-gasification of waste tyres with sugarcane bagasse on both hydrogen and CNT yield has not been investigated.
