Title: | Carbon nanotube sponges as an enrichment material for aromatic volatile organic compounds |
Author(s): | Jang Y; Bang J; Seon YS; You DW; Oh JS; Jung KW; |
Address: | "Department of Chemistry and Nanoscience & Technology Institute, Wonkwang University, 460 Iksandaero, Jeonbuk 54538, Republic of Korea. Dyntem Corporation, 460 Iksandaero, Iksan, Jeonbuk 54538, Republic of Korea. Department of Chemistry and Nanoscience & Technology Institute, Wonkwang University, 460 Iksandaero, Jeonbuk 54538, Republic of Korea. Electronic address: kwjung@wku.ac.kr" |
DOI: | 10.1016/j.chroma.2019.460840 |
ISSN/ISBN: | 1873-3778 (Electronic) 0021-9673 (Linking) |
Abstract: | "Sensitive methods are required for in situ monitoring of volatile organic compounds (VOCs). Herein, carbon nanotube (CNT) sponges were investigated as a new type of adsorbent for enriching trace aromatic VOCs. A square pillar configuration (3 mm x 3 mm x 45 mm, 5 mg) of a CNT sponge was enclosed in a glass tube (4 mm i.d.). After accumulating the sample vapor, a direct current pulse (26 V, 0.5-3.0 s) through the CNT sponge allowed narrow desorption bandwidths of 0.48-0.84 s (with a photoionization detector) and 1.2 s (with a flame ionization detector) and high desorption efficiency (>96.5%). Gas chromatographic analysis of a nine-component VOC mixture (100 mL adsorption volume) gave enrichment factors of 88 (benzene) to 323 (toluene and m-xylene) with detection limits in the range of 0.9-2.6 ppb (v/v). These results demonstrate that CNT sponges are a promising preconcentrator material for trace detection of VOCs. The adsorption breakthrough experiments exhibited good correlation with the kinetic adsorption and Langmuir isotherm models. The maximum adsorption capacities of the CNT sponge increased in the order benzene (0.13 mg/g) < toluene (2.45 mg/g) < ethylbenzene (13.90 mg/g) < o-xylene (14.31 mg/g), with R(2) values of >0.95. The rollup phenomena observed during multicomponent adsorption were explained by the competitive displacement or adsorption affinities of aromatic VOCs. The feasibility of the CNT sponge preconcentrator in a real environment was tested for interfering species (NO(2) and NH(3)), laboratory air, and a human breath sample and demonstrated similar performance as in the controlled nine-component tests" |
Keywords: | "Adsorption Benzene/analysis Benzene Derivatives/analysis Chromatography, Gas Kinetics Nanotubes, Carbon/*chemistry Toluene/analysis Volatile Organic Compounds/*analysis Xylenes/analysis Adsorption capacity Aromatic volatile organic compounds Carbon nanotu;" |
Notes: | "MedlineJang, Yeonhee Bang, Juyeon Seon, Yeong-Sik You, Dong-Wook Oh, Jun-Sik Jung, Kwang-Woo eng Netherlands 2020/01/18 J Chromatogr A. 2020 Apr 26; 1617:460840. doi: 10.1016/j.chroma.2019.460840. Epub 2019 Dec 31" |