A review on prominent animal and municipal wastes as potential feedstocks for solar pyrolysis for biochar production

[Display omitted] •Solar pyrolysis systems' technological and economic challenges are highlighted.•Physicochemical evaluations of prominent animal/municipal wastes are analyzed.•Attributes of plant, animal, and municipal wastes chars are compared.•Copyrolyzing biomass and municipal wastes will produce high quality and yield chars. Biochar is a highly rich carbonaceous material, which when applied to soil renders numerous benefits to plants and the environment. The role of biochar in agriculture is expected to expand rapidly as the need to protect the climate, manage organic waste, and produce food has risen significantly. Hence, continuous research on the production and application of biochar is important. With this perspective, the present study provides a detailed review on the physicochemical analyses of some prominent animal and municipal wastes as potential feedstocks for pyrolysis/solar pyrolysis biochar generation. The review also presents a comparative assessment of previous solar pyrolysis studies. The technical and economic challenges associated with the solar pyrolysis systems are also covered in this critique. The review will be helpful for peer researchers when choosing feedstock for solar pyrolysis and producing biochar.