The Application of Biochar for CO(2) Capture: Influence of Biochar Preparation and CO(2) Capture Reactors

[Image: see text] This work investigates three types of biochar (bamboo charcoal, wood pellet, and coconut shell) for postcombustion carbon capture. Each biochar is structurally modified through physical (H(2)O, CO(2)) and chemical (ZnCl(2), KOH, H(3)PO(4)) activation to improve carbon capture performance. Three methods (CO(2) adsorption isotherms, CO(2) fixed-bed adsorption, and thermogravimetric analysis) are used to determine the CO(2) adsorption capacity. The results show that a more than 2.35 mmol·g(–1) (1 bar, 298 K) CO(2) capture capacity was achieved using the activated biochar samples. It is also demonstrated that the CO(2) capture performance by biochar depends on multiple surface and textural properties. A high surface area and pore volume of biochar resulted in an enhanced CO(2) capture capacity. Furthermore, the O*/C ratio and pore width show a negative correlation with the CO(2) capture capacity of biochars.