CO2 bubble absorption enhancement in methanol-based nanofluids

In this study, the nanoparticles (i.e. SiO2 and Al2O3 nanoparticles) and methanol are combined into SiO2/methanol and Al2O3/methanol nanofluids to enhance the CO2 absorption rate of the base fluid (methanol). The absorption experiments are performed in the bubble type absorber system equipped with mass flow controller (MFC), mass flow meter (MFM) and silica gel (which can remove the methanol vapor existing in the outlet gases). The parametric analysis on the effects of the particle species and concentrations on CO2 bubble absorption rate is carried out. The particle concentration ranges from 0.005 to 0.5 vol%. It is found that the CO2 absorption rate is enhanced up to 4.5% at 0.01 vol% of Al2O3/methanol nanofluids at 20 °C, and 5.6% at 0.01 vol% of SiO2/methanol nanofluids at −20 °C, respectively.

► The carbon dioxide (CO2) emissions cause the global warming problem.
► The effective absorption ratios at −20 °C are higher than those at 20 °C.
► CO2 absorption rate by the methanol-based nanofluid is enhanced up to ∼5.6%.
► Methanol-based nanofluid will be a promising candidate for CO2 absorption enhancement.