Competitive sorption used to probe strong hydrogen bonding sites for weak organic acids on carbon nanotubes

摘要

9 páginas.-- 3 figuras.-- 31 referencias.-- Supporting Information: characteristics of the three multiwalled CNTs; selected physicochemical properties of sorbates; Freundlich model fits to sorption and competitive sorption data of monaromatics by CNTs; adsorption kinetics of BA, DNP, and NB onto C−CNT at pH 7 and adsorption kinetics of MBPh, MBA, and PTA onto C−CNT at pH 6; comparison of sorption isotherms of a given adsobate on hydroxylated (H−), carboxylated (C−), and graphitized (G−)CNTs at pH 7.0; zeta potential measurements for the three CNTs; pH records of the NB adsorption on CNTs at initial pH 7.0; titration curves of the three CNTs from pH 3−12; consumption of OH− as a function of pH for the three CNTs from the titration curves; sorbed concentration of NB on three CNTs as function of sorbed competitor concentration at pH 7.0 and displacement efficiency (DE %) of BA or DNP as function of sorbed competitor concentration; sorbed concentration of MBPh on C−CNT as function of amount sorbed of competitors, MBA and PTA at pH 4 and pH 6 at fixed initial concentration of MBPh of 0.2 Mm; and solution pH change versus moles BA−/DNP− adsorbed for (A, C, E) H−CNT and (B, D, F) C−CNT without or with cosolute. This material is available free of charge via the Internet at http://pubs.acs.org