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Ca-rich solid waste, carbide slag, was adopted to prepare the CaO-based sorbent for CO2uptake at elevated temperature. To alleviate the elutriation issue of CaO-based sorbent from the calcium looping system, the granulation of carbide slag was conducted via an extrusion-spheronization method. Calcium aluminate cement possessing excellent refractory property was selected as the binder. A range of cement-bound carbide slag pellets were prepared with the active CaO content varying from 25 to 70 wt %. The incorporation of calcium aluminate cement significantly decreases the CO2capture capacities of the carbide slag pellets due to the irreversible consumption of active CaO by the silicates or aluminates within the cement. However, the average compression strengths of the fresh (3.29–9.82 MPa) and calcined (0.47–2.46 MPa) cement-bound carbide slag pellets gradually increase with the increase of cement addition. Additionally, the addition of rice husk can improve the CO2capture performance of the cement-bound carbide slag pellets during the fast CO2capture stage because of the generation of in stiu pores and cavities within the sorbent pellets. Although the cyclic CO2capture performance of the cement-bound carbide slag pellets degrades under oxy-fuel calcination condition, to some extent, the low-cost and easily scaled-up preparation route may offsets the increased CO2avoid cost because of the loss-in-capacity.

A biomass-based activated carbon, utilized for direct carbon fuel cells (DCFCs), is prepared from bamboo scraps under different activation temperatures, activation times, and impregnation ratios. The K2CO3is employed as the activating agent, while the activated carbon is treated in HNO3solution for the purpose of surface modification and ash removal. The applicability of the prepared activated carbon for DCFCs is evaluated by a fluidized bed electrode direct carbon fuel cell anode. It is found that the BET surface area of the activated carbon could reach 1264 m2g–1under the following conditions: activation temperature, 1173 K; activation time, 2 h; impregnation ratio, 1. The content and diversity of the surface oxygen functional groups of the activated carbon could be well improved through the HNO3treatment, and the ash content is notably reduced. Differently, the BET surface area is slightly reduced while the electrical resistivity is remarkably increased. The optimal HNO3solution concentration is estimated to be 2 mol L–1, giving the treated bamboo-based activated carbon outstanding polarization performance among the tested carbon fuels.