The synthetic CaO/Ca3Al2O6 (prepared from carbide slag, aluminum nitrate enneahydrate, and glycerol water solution by combustion synthesis) as a CO2 sorbent discharged from the CO2 capture cycles using the calcium looping was used to remove HCl after a series of carbonation/calcination cycles. The effects of chlorination temperature, HCl concentration, presence of CO2, and cycle number on the HCl absorption by the CaO/Ca3Al2O6 sorbent after the repetitive carbonation/calcination cycles for CO2 capture were discussed. In addition, the HCl absorption capacities of the CaO/Ca3Al2O6 sorbent and the carbide slag were compared. The chlorination products of the CaO/Ca3Al2O6 sorbent after 1 h HCl absorption are CaClOH, CaO, and Ca3Al2O6 detected by XRD analysis. Among 600-800 degrees C, the CaO/Ca3Al2O6 sorbent from the carbonation/calcination cycles achieves the highest HCl absorption capacity at 700 degrees C. The HCl absorption capacity of the cycled CaO/Ca3Al2O6 sorbent rises as HCl concentration increases. CO2 is adverse to the HCl absorption by the cycled CaO/Ca3Al2O6 sorbent in the chlorination process. With the carbonation/calcination cycle number increasing from 0 to 50, the CaO/Ca3Al2O6 sorbent after 5 cycles exhibits the highest HCl absorption capacity. HCl absorption capacities of the cycled CaO/Ca3Al2O6 sorbent after 20 and 50 cycles were 0.18 and 0.13 g/g, which were 2.3 and 2.6 times as high as those of the cycled carbide slag after the same cycles, respectively. (C) 2015 Elsevier B.V. All rights reserved.