https://doi.org/10.1016/j.cep.2020.108002
In the above referenced paper, Figure 5 shows that the reduce of CO2 inlet concentration from 9 to 20% resulted in an increase of mass transfer coefficient. The results were obtained with and without the addition of Fe3O4 nanoparticles. It is also noted that the presence of 0.2 g/L nanoparticles enhanced the mass transfer coefficient.