School of Environmental Engineering, Jiangsu Key Laboratory of Industrial Pollution Control and Resource Reuse, Xuzhou University of Technology, Xuzhou, 221018, PR China; Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL, 32611, USA; Jiangsu Key Laboratory of Vehicle Emissions Control, Center of Modern Analysis, Nanjing University, Nanjing, 210093, PR China.
School of Environmental Engineering, Jiangsu Key Laboratory of Industrial Pollution Control and Resource Reuse, Xuzhou University of Technology, Xuzhou, 221018, PR China; Department of Agricultural and Biological Engineering, University of Florida, Gainesville, FL, 32611, USA.
Chemosphere. 2020 Apr;245:125664. doi: 10.1016/j.chemosphere.2019.125664. Epub 2019 Dec 18.
Most of the volatile organic compounds (VOCs) are toxic and harmful to human health and environment. In this study, hydrochars activated with CO 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 m/g), whereas activated hydrochars showed much higher values (up to 1308 m/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 (R > 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 CO activation, are sufficient for VOC abatement.
大多数挥发性有机化合物（VOCs）对人类健康和环境都具有毒性和危害性。在这项研究中，使用 CO 活化的水热炭来去除 VOCs。两种典型的 VOCs，丙酮和环己烷，被用作“模型”吸附质来评估水热炭的性能。原始水热炭的比表面积较小（<8 m/g），而活化后的水热炭则具有更高的值（高达 1308 m/g）。因此，VOCs 在原始水热炭上的吸附量（13.24-24.64 mg/g）低于在活化水热炭上的吸附量（39.42-121.74 mg/g）。两种 VOCs 在水热炭上的吸附都是放热的。此外，VOC 去除率与水热炭比表面积之间存在显著相关性（R>0.91）。这些结果表明，主要的作用机制是物理吸附。升高实验温度（80-139°C）会将 VOCs 从水热炭上解吸下来。由于环己烷的沸点较高，因此其解吸需要比丙酮更高的温度。通过五次连续的吸附-解吸循环，证实了活化水热炭对两种 VOCs 的可重复使用性。总体结果表明，水热炭，特别是经过 CO 活化后，对于 VOC 的去除是足够有效的。
