Department of Civil and Environmental Engineering , University of Alberta , Edmonton , Alberta T6G 1H9 , Canada.
Environmental Quality Office , Ford Motor Company , Dearborn , Michigan 48126 , United States.
Environ Sci Technol. 2019 Mar 5;53(5):2647-2659. doi: 10.1021/acs.est.8b05664. Epub 2019 Feb 22.
A two-dimensional heterogeneous mathematical model was developed and validated to study the effect of relative humidity on volatile organic compound (VOC) adsorption onto activated carbon. The dynamic adsorption model consists of the macroscopic mass, momentum, and energy conservation equations and includes a multicomponent adsorption isotherm to predict the competitive adsorption equilibria between VOC and water vapor, which is described by an extended Manes method. Experimental verifications show that the model predicted the breakthrough profiles during competitive adsorption of the studied VOCs (2-propanol, acetone, n-butanol, toluene, 1,2,4-trimethylbenzene) at relative humidity range 0-95% with an overall mean relative absolute error (MRAE) of 11.8% for dry (0% RH) conditions and 17.2% for humid (55 and 95% RH) conditions, and normalized root-mean-square error (NRMSE) of 5.5 and 8.4% for dry and humid conditions, respectively. Sensitivity analysis was also conducted to test the robustness of the model in accounting for the impact of relative humidity on VOC adsorption by varying the adsorption temperature. Good agreement was observed between the experimental and simulated results with an overall MRAE of 12.4 and 7.1% for the breakthrough profiles and adsorption capacity, respectively. The model can be used to quantify the impact of carrier gas relative humidity during adsorption of contaminants from gas streams, which is useful when optimizing adsorber design and operating conditions.
建立并验证了一个二维非均相数学模型，以研究相对湿度对活性炭吸附挥发性有机化合物（VOC）的影响。动态吸附模型由宏观质量、动量和能量守恒方程组成，包括一个多组分吸附等温线，以预测 VOC 和水蒸气之间的竞争吸附平衡，这由扩展的 Manes 方法来描述。实验验证表明，该模型预测了研究的 VOC（2-丙醇、丙酮、正丁醇、甲苯、1,2,4-三甲苯）在相对湿度为 0-95%范围内的竞争吸附穿透曲线，在干燥（0%RH）条件下的总体平均相对绝对误差（MRAE）为 11.8%，在潮湿（55%和 95%RH）条件下的 MRAE 为 17.2%，干燥和潮湿条件下的归一化均方根误差（NRMSE）分别为 5.5%和 8.4%。还进行了敏感性分析，以通过改变吸附温度来测试模型在考虑相对湿度对 VOC 吸附的影响方面的稳健性。实验结果和模拟结果之间具有良好的一致性，穿透曲线和吸附容量的总体 MRAE 分别为 12.4%和 7.1%。该模型可用于量化气流中污染物吸附过程中载气相对湿度的影响，这在优化吸附器设计和操作条件时非常有用。
