Article

Adsorption of arsenic on multiwall carbon nanotube-zirconia nanohybrid for potential drinking water purification

Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, NJ 07102, USA.
Journal of Colloid and Interface Science (Impact Factor: 3.55). 02/2012; 375(1):154-9. DOI: 10.1016/j.jcis.2012.01.063
Source: PubMed

ABSTRACT The adsorptive removal of arsenic from water using a multiwall carbon nanotube-zirconia nanohybrid (MWCNT-ZrO(2)) is presented. The MWCNT-ZrO(2) with 4.85% zirconia was effective in meeting the drinking water standard levels of 10 μg L(-1). The absorption capacity of the composite were 2000 μg g(-1) and 5000 μg g(-1) for As(III) and As(V) respectively, which were significantly higher than those reported previously for iron oxide coated MWCNTs. The adsorption of As(V) on MWCNT-ZrO(2) was faster than that of As(III), and a pseudo-second order rate equation effectively described the uptake kinetics. The adsorption isotherms for As(III) and As(V) fitted both the Langmuir and Freundlich models. A major advantage of the MWCNT-ZrO(2) was that the adsorption capacity was not a function of pH.

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