Influence of biomass feedstock on biochar based CO2 capture

https://doi.org/10.1016/j.ccst.2022.100059

“There is a variation in the CO₂ adsorption capacity of biochar produced from different raw materials. Creamer et al. (Creamer et al., 2014). employed biochar produced from the co-pyrolysis of sugarcane bagasse (BG) and hickory wood (HW) to the adsorption of CO₂ at 25 ^oC. Biochar produced with larger surface areas showed a higher CO₂ adsorption capacity (73.55 mg/g at 25 ^oC). More active sites for CO₂ adsorption are provided with a higher surface area, leading to a greater adsorption capacity (Creamer and Gao, 2016). Serafin et al. (Serafin et al., 2017) found that biochars produced from carrot peels at 700 °C showed CO₂ adsorption capacities of 4.18 mol/kg at 25 °C. Xu et al. (Xu et al., 2016)produced biochars from sewage sludge, pig manure, and wheat straw with the CO₂ adsorption capacities of 0.41, 0.53, and 0.78 mol/kg respectively at 25 °C. Igalavithana et al.⁹⁹produced biochar from feedstock mixtures of food waste and wood waste in different proportions. In Fig. 5, it revealed that when wood wastes occupies the highest proportion, the biochar owned the strongest CO₂ adsorption capacity, while a higher proportion of food wastes in the raw material was detrimental to CO₂ adsorption. Feedstock types influenced the biochar chemical and physical characteristics, and the high percentage of hetero atoms (N and S) on the surface contributed to high CO₂ adsorption. If a large-scale application of biomass adsorbents for CO₂ capture is desired, it requires the development of more biomass feedstocks and techno-economic analysis.”