TY  - JOUR
AU  - Li, C.
AU  - Schaeffer, A.
AU  - Sequaris, J.M.
AU  - Laszlo, K.
AU  - Toth, A.
AU  - Tombacz, E.
AU  - Vereecken, H.
AU  - Ji, R.
AU  - Klumpp, E.
TI  - Surface-associated metal catalyst enhances the sorption of perfluorooctanoic acid to multi-walled carbon nanotubes
JO  - Journal of colloid and interface science
VL  - 377
SN  - 0021-9797
CY  - Amsterdam [u.a.]
PB  - Elsevier
M1  - PreJuSER-22330
SP  - 342 - 346
PY  - 2012
N1  - Chengliang Li is grateful for a scholarship from the Deutscher Akademischer Austausch Dienst (DAAD). This study was financed by the National Natural Science Foundation of China (Project Nos.: 20977043 and 20777033).
AB  - The perfluorooctanoic acid (PFOA) sorption behavior of two commercial multi-walled carbon nanotubes (MWCNTs) (C 150 P from Bayer MaterialScience: BA and C-MWNTs from NanoTechLabs Inc.: CP) was investigated from aqueous solution. The BA nanotubes contained Co/Mn/Mg/Al catalysts both on their outer surface and in the inner bore while CP contained Fe-based catalyst typically within the tubes. The adsorption isotherms of (14)C-radiolabeled PFOA were measured by batch experiments and fitted to the Freundlich model (r(2)>0.92). The adsorption affinity and capacity on BA were significantly higher than on CP. Increasing the pH reduced the adsorption of PFOA due to the electrostatic interaction between the pH-sensitive surface and the adsorbate. Increasing the NaCl concentration led to the aggregation of the MWCNTs reducing the available surface and thus the adsorption capacity. Removal of the catalyst from the outer surface of BA changed the electrophoretic mobility from a positive to a negative value and also decreased the adsorbed amount of PFOA. The surface charge of the surface-associated metal catalyst favors the electrostatic sorption of PFOA. Such surface modifications may be a promising way to improve the sorption capacity of MWCNTs for pollutants such as PFOA and to broaden their potential application in water purification.
KW  - Adsorption
KW  - Aluminum: chemistry
KW  - Cobalt: chemistry
KW  - Fluorocarbons: chemistry
KW  - Hydrogen-Ion Concentration
KW  - Magnesium: chemistry
KW  - Manganese: chemistry
KW  - Nanotubes, Carbon: chemistry
KW  - Octanoic Acids: chemistry
KW  - Osmolar Concentration
KW  - Surface Properties
KW  - Fluorocarbons (NLM Chemicals)
KW  - Nanotubes, Carbon (NLM Chemicals)
KW  - Octanoic Acids (NLM Chemicals)
KW  - perfluorooctanoic acid (NLM Chemicals)
KW  - Aluminum (NLM Chemicals)
KW  - Magnesium (NLM Chemicals)
KW  - Manganese (NLM Chemicals)
KW  - Cobalt (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:22494685
UR  - <Go to ISI:>//WOS:000304432400046
DO  - DOI:10.1016/j.jcis.2012.03.038
UR  - https://juser.fz-juelich.de/record/22330
ER  -