https://doi.org/10.1016/j.ccst.2022.100059
“Similar with feedstock types, the structural and compositional features of biochar, such as surface area, pore morphologies, surface functional groups, and elemental compositions, are also affected by the pyrolysis temperature. (Tag et al., 2016) For example, Chatterjee (Chatterjee et al., 2020) et al. investigated the influence of pyrolysis temperature (500, 600, 700, 800 °C) on the properties and CO2 adsorption capacities of biochar derived from herbaceous and agro-industrial feedstocks. The adsorption capacity of all biochars increased gradually as the temperature increased from 500 °C to 600 °C (Fig. 6). This is because biochar produced in low temperature has a poor porous structure, low specific surface area, and is easily blocked by tar formed during biomass pyrolysis (Patra et al., 2021). Although the nitrogen content decreased with increasing temperature, the carbon content increased significantly, thus contributing to the improvement in CO2 adsorption capacity. However, further increasing the pyrolysis temperature to 800 °C decreased the adsorption capacity values greatly compared to that obtained at 700 °C. This could be attributed to the decrease in nitrogen content and the destruction of surface porosity at higher temperature (800 °C). As a result, choosing an appropriate pyrolysis temperature involves a tradeoff between the surface and chemical qualities discussed above.”