Interaction of phenol and dopamine with commercial MWCNTs

► Adsorption of phenol and dopamine is compared on commercial MWCNTs. ► Adsorption data of dopamine are reported first time. ► Different pH dependence of adsorption on non-treated and oxidized CNTs. ► The surface coverage is 8-12% and 21-33% with phenol and dopamine, respectively. ► Interaction is stronger but capacity is much smaller than with activated carbons.