Adsorption of acetone and cyclohexane onto CO2 activated hydrochars

Xueyang Zhang, Wei Xiang, Bing Wang, June Fang, Weixin Zou, Feng He, Yuncong Li, Daniel C.W. Tsang, Yong Sik Ok, Bin Gao

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Most of the volatile organic compounds (VOCs) are toxic and harmful to human health and environment. In this study, hydrochars activated with CO2 were applied to remove VOCs. Two typical VOCs, acetone and cyclohexane, were used as the ‘model’ adsorbates to evaluate hydrochars’ performance. Specific surface areas of pristine hydrochars were small (<8 m2/g), whereas activated hydrochars showed much higher values (up to 1308 m2/g). As a result, the adsorption of VOCs onto the pristine hydrochars (13.24–24.64 mg/g) was lower than that of the activated ones (39.42–121.74 mg/g). The adsorption of the two VOCs onto the hydrochars was exothermal. In addition, there were significant correlations (R2 > 0.91) between the VOC removal and hydrochars’ specific surface area. These results suggest that the governing mechanism was mainly physical adsorption. Increasing experimental temperature (80–139 °C) desorbed the VOCs from the hydrochars. Due to its higher boiling point, cyclohexane desorption required a higher temperature than acetone desorption. The reusability of the activated hydrochars to the two VOCs was confirmed by five continuous adsorption-desorption cycles. The overall results indicated that hydrochars, particularly after CO2 activation, are sufficient for VOC abatement.

Original languageEnglish
Article number125664
JournalChemosphere
Volume245
DOIs
Publication statusPublished - 2020 Apr

    Fingerprint

Keywords

  • Activated carbon
  • Air pollution control
  • Engineered biochar
  • Green remediation
  • VOC removal

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Chemistry(all)
  • Pollution
  • Health, Toxicology and Mutagenesis

Cite this

Zhang, X., Xiang, W., Wang, B., Fang, J., Zou, W., He, F., Li, Y., Tsang, D. C. W., Ok, Y. S., & Gao, B. (2020). Adsorption of acetone and cyclohexane onto CO2 activated hydrochars. Chemosphere, 245, [125664]. https://doi.org/10.1016/j.chemosphere.2019.125664