Evaluation of physico-chemical and structural properties of biochar produced from pyrolysis of urban biowaste

Understanding proper utilization and evaluation of biowaste materials in any metropolitan city across the world is crucial with respect to diminishing air pollution and combating climate change. This study evaluated the physico-chemical and structural properties of biochar produced from biowaste materials collected from Delhi, viz., sugarcane bagasse, brinjal stem, and citrus peel pyrolysed at 450 and 600 °C for 30 and 60 min, respectively, in the muffle furnace. Biochar yields for brinjal stem and citrus peel were in the range of 31–40%, while for sugarcane bagasse, they were 18–39% at different pyrolysis conditions. Pyrolysis temperatures had a significant effect, while pyrolysis residence time had no significant effect on the physico-chemical and structural properties of biochar. Our study also found that the macro- and micropores and more heat resistance properties in biochar which were produced at 600 °C for 30–60 min. TGA, FTIR, and XRD analysis showed that biochar produced at 600 °C had more thermal stability, functional groups, and mineral compositions. This study, for the first time, provides a comprehensive evaluation of biochar produced from different biowaste materials collected in Delhi. The results of our study provide a clear perception that proper utilization of urban biowaste materials as biochar would be a possible pathway for biowaste management in metropolitan cities with added environmental co-benefits. Graphical abstract