Experimental investigation of CO₂ absorption enhancement with functionalized MWCNT

This study investigated the CO₂ absorption on the functionalized multi-walled carbon nanotubes with 1,8-diaminooctane (aMWCNT) in pure water solution and N-methyl diethanolamine (MDEA). Hexadecyltrimethylammonium bromide (CTAB) was used as a surfactant to disperse the nanofluid solution. The results showed that at a concentration of 0.005 wt% aMWCNT in water at 16 bar, the CO₂ absorption capacity increased by 17.5% compared to pure water. It was found that adding aMWCNT to 15wt% MDEA solution improves the absorption rate. However, the highest absorption was at 0.005wt% aMWCNT in the solvent. The absorption capacity increased to 59% at the highest pressure in 15%wt MDEA solution, including aMWCNT, compared to 15%wt MDEA solution. It can be concluded that adding aMWCNT has advantages such as increasing the absorption capacity and reducing the heat of absorption.