Hebei Key Laboratory of Close-to-Nature Restoration Technology of Wetlands, School of Eco-Environment, Hebei University, Baoding, 071002, China; Institute of Xiong'an New Area, Hebei University, Baoding, 071002, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
Environ Pollut. 2024 May 1;348:123879. doi: 10.1016/j.envpol.2024.123879. Epub 2024 Mar 26.
Desorption is a critical process in the recovery or post-treatment of adsorbents saturated with volatile organic compounds (VOCs). In this study, the thermal desorption behaviors for eight VOCs on hypercrosslinked polymeric resin (HPR) and macroporous polymeric resin (MPR) were investigated through isothermal desorption and temperature programmed desorption (TPD). Compared with MPR, HPR with more micropores exhibited a lower desorption rate constant, lower desorption efficiency and higher desorption activation energy due to the strong binding energy generated between VOCs molecules and narrow micropores. As the polarizability of VOCs increased, the desorption rate constants on two porous polymeric resins decreased, while the desorption activation energy showed an incremental trend. Excellent linear correlations were observed between VOC polarizability and desorption rate constants (R = 0.957 for HPR and R = 0.940 for MPR) as well as between VOC polarizability and desorption activation energy (R = 0.981 for HPR and R = 0.969 for MPR). Furthermore, a polyparameter linear free energy relationship (PP-LFER) was developed to explore the influences of intermolecular interactions on desorption behaviors of VOCs on porous polymeric resins. The results indicated that the dispersive interaction, which is directly related to polarizability of VOCs, was the primary factor influencing the desorption activation energy of VOCs on porous polymeric resins. The find from this study helps evaluate fleetly and availably the desorption properties of VOCs based on their polarizability.
解吸是吸附剂吸附挥发性有机化合物（VOCs）饱和后回收或后处理的关键过程。在这项研究中，通过等温解吸和程序升温解吸（TPD）研究了八种 VOC 在超交联聚合物树脂（HPR）和大孔聚合物树脂（MPR）上的热解吸行为。与 MPR 相比，具有更多微孔的 HPR 由于 VOC 分子与狭窄微孔之间产生的强结合能，表现出较低的解吸速率常数、较低的解吸效率和较高的解吸活化能。随着 VOCs 极化率的增加，两种多孔聚合物树脂上的解吸速率常数降低，而解吸活化能呈递增趋势。在 HPR 中，VOC 极化率与解吸速率常数之间存在极好的线性相关性（R = 0.957），在 MPR 中，VOC 极化率与解吸速率常数之间存在极好的线性相关性（R = 0.940）。同样，在 HPR 中，VOC 极化率与解吸活化能之间存在极好的线性相关性（R = 0.981），在 MPR 中，VOC 极化率与解吸活化能之间存在极好的线性相关性（R = 0.969）。此外，开发了一个多参数线性自由能关系（PP-LFER）来探索分子间相互作用对 VOC 在多孔聚合物树脂上解吸行为的影响。结果表明，与 VOC 极化率直接相关的色散相互作用是影响 VOC 在多孔聚合物树脂上解吸活化能的主要因素。本研究的结果有助于根据 VOC 的极化率快速有效地评估 VOC 的解吸性能。
