“The promotion effects of Na, K, and Ca (15 wt% against Al2O3) were investigated on Ni/γ-Al2O3 by Kosaka et al. (Kosaka et al., 2021). It was found that Ni/γ-Al2O3 had negligible CO2 capture ability and thus low methanation yield. The CH4 yield increased to 188 and 134 mmol/kg-DFM after Na and K modification, respectively. The CO2 uptake capacity of K modification was higher than Na, but the CH4 selectivity was much lower (93% vs. 61%) with a considerable production of CO. Ca modification showed a much weaker promotion effect, with the CH4 yield of 58 mmol/kg-DFM, possibly because of the high stability of CaCO3 at the operation temperature of 450°C, which was thought to be incompatible with the CaCO3 decarbonation temperature.”
Detailed ICCU performance of Na, K and Ca supported Ni/ Al2O3 is shown below:
https://doi.org/10.1021/acssuschemeng.0c07162