Chemical Papers, cilt.78, sa.2, ss.833-849, 2024 (SCI-Expanded)
Water pollution caused by heavy metals is one of the most important issues threatening the environment. The study, presented here was focused on the removal of heavy metal Cu2+ ions from aqueous solution by using pristine multi-walled carbon nanotubes (p-MWCNT), acid treated MWCNTs (a-MWCNTs) and unzipped MWCNTs (u-MWCNTs). The size dependency of MWCNTs on the adsorption of Cu2+ ions was evaluated. Moreover, pH, adsorbent dosage, initial metal ion concentration and temperature effects on the adsorption process were explored. The maximum adsorption efficiency was found to be 98.5% for u-MWCNTs that is fabricated from the layered MWCNTs having an outer diameter of 50–80 nm and an inner diameter of 10–20 nm at 0.5 g L−1 adsorbent mass. The absorption kinetic data fitted best to the pseudo-second-order model. The thermodynamic assessments indicated that the adsorption was endothermic and randomness process. Graphical Abstract: [Figure not available: see fulltext.]