Adsorption of selected volatile organic vapors on multiwall carbon nanotubes.
Carbon nanotubes are expected to play an important role in sensing, pollution treatment and separation techniques. This study examines the adsorption behaviors of volatile organic compounds (VOCs), n-hexane, benzene, trichloroethylene and acetone on two multiwall carbon nanotubes (MWCNTs), CNT1 and CNT2. Among these VOCs, acetone exhibits the highest adsorption capacity. The highest adsorption enthalpies and desorption energies of acetone were also observed. The strong chemical interactions between acetone and both MWCNTs may be the result from chemisorption on the topological defects. The adsorption heats of trichloroethylene, benzene, and n-hexane are indicative of physisorption on the surfaces of both MWCNTs. CNT2 presents a higher adsorption capacity than CNT1 due to the existence of an exterior amorphous carbon layer on CNT2. The amorphous carbon enhances the adsorption capacity of organic chemicals on carbon nanotubes. The morphological and structure order of carbon nanotubes are the primary affects on the adsorption process of organic chemicals.
Shih
Yang-hsin
YH
Department of Soil and Environmental Sciences, Center of Nanoscience and Nanotechnolgy, National Chung Hsing University, Taichung 402, Taiwan, ROC. yhs@nchu.edu.tw
Li
Mei-syue
MS
D000096:Acetone / Q000737:chemistry*; D000327:Adsorption; D000393:Air Pollutants / Q000737:chemistry*; D000397:Air Pollution / Q000517:prevention & control; D006838:Hydrocarbons / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013816:Thermodynamics; D014835:Volatilization
D000393:Air Pollutants; D006838:Hydrocarbons; D037742:Nanotubes, Carbon; D000096:Acetone