Calcium oxide derived from different calcium precursors is emerged as one of the most potential candidates to trap CO2 and prevent its emission into the atmosphere [1–3], based on the reversible carbonation/calcination reaction, especially when the pilot scale facilities have been successfully demonstrated (1 MWt and 1.7 MWt) [4,5]. However, there are still problems for this tech- nology and one issue is the decline in sorbent carbonation capacity with the number of cycle which affects the process economics [6]. Sintering of the sorbents is believed to be the major cause of deactivation due to the great expansion and shrinkage of crystal struc- ture of CaO created during the calcination–carbonation process, resulting in structure collapse as evidenced by the change of sor- bent surface texture, i.e., the loss of suitable pore volume after sev- eral cycles [7,8]. Therefore, it is the most important step for large scale application of calcium based sorbents for CO2 capture to solve the problems of rapid decline in CO2 capture capability.
Great effort has been done to maintain high reactivity of sorbents for CO2 capture by different methods [9–17], among which creating synthetic sorbents by adding supporting materials is regarded as one of the most effective ways to prepare high-performance CaO- based sorbents, attributed to the inert material acting as the frame- work and thus effectively reduced sintering of CaO sorbents during the multiple cycles [18]. The CaO–MgO absorbent was prepared by the co-precipitation method achieving excellent cyclic stability but