Competitive adsorption of phenol and 3-chlorophenol on purified MWCNTs

Ajna Tóth; Andrea Törőcsik; Etelka Tombácz; Krisztina László

doi:10.1016/j.jcis.2012.07.064

Competitive adsorption of phenol and 3-chlorophenol on purified MWCNTs

J Colloid Interface Sci. 2012 Dec 1;387(1):244-9. doi: 10.1016/j.jcis.2012.07.064. Epub 2012 Aug 3.

Authors

Ajna Tóth¹, Andrea Törőcsik, Etelka Tombácz, Krisztina László

Affiliation

¹ Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, H-1521 Budapest, Hungary.

PMID: 22939426
DOI: 10.1016/j.jcis.2012.07.064

Abstract

A commercial multiwall carbon nanotube and its carboxylated derivate (CNTC and COOHC, respectively) was used after purification to study the competitive adsorption of phenol (P) and m-chlorophenol (CP) from 0.1 M aqueous NaCl solutions without external pH control. The adsorption takes place practically exclusively on the external surface of the nanotubes. The uptake of P is suppressed in comparison to its single solute behaviour on both nanotubes, independently of the initial pollutant concentration. The uptake of CP however is more sensitive to the concentration and the surface chemistry of the nanotube. The measured co-adsorption isotherms were compared to the isotherms calculated from the competitive Langmuir model (CLM). Preferential adsorption of CP was observed in about 95% of the relative concentration range. The total adsorption may exceed the corresponding single component sorption capacity.