Vuong François, Chauveau Romain, Grevillot Georges, Marsteau Stéphanie, Silvente Eric, Vallieres Cécile
a Laboratoire Réactions et Génie des Procédés, CNRS, Université de Lorraine , Nancy , France.
b Laboratoire de Filtration et d'Adsorption-INRS , Nancy , France.
J Occup Environ Hyg. 2016 Sep;13(9):675-89. doi: 10.1080/15459624.2016.1166368.
In this study, equilibria, breakthrough curves, and breakthrough times were predicted for three binary mixtures of four volatile organic compounds (VOCs) using a model based on partial differential equations of dynamic adsorption coupling a mass balance, a simple Linear Driving Force (LDF) hypothesis to describe the kinetics, and the well-known Extended-Langmuir (EL) equilibrium model. The model aims to predict with a limited complexity, the BTCs of respirator cartridges exposed to binary vapor mixtures from equilibria and kinetics data obtained from single component. In the model, multicomponent mass transfer was simplified to use only single dynamic adsorption data. The EL expression used in this study predicted equilibria with relatively good accuracy for acetone/ethanol and ethanol/cyclohexane mixtures, but the prediction of cyclohexane uptake when mixed with heptane is less satisfactory. The BTCs given by the model were compared to experimental BTCs to determine the accuracy of the model and the impact of the approximation on mass transfer coefficients. From BTCs, breakthrough times at 10% of the exposure concentration t10% were determined. All t10% were predicted within 20% of the experimental values, and 63% of the breakthrough times were predicted within a 10% error. This study demonstrated that a simple mass balance combined with kinetic approximations is sufficient to predict lifetime for respirator cartridges exposed to VOC mixtures. It also showed that a commonly adopted approach to describe multicomponent adsorption based on volatility of VOC rather than adsorption equilibrium greatly overestimated the breakthrough times.
在本研究中，使用基于动态吸附偏微分方程的模型预测了四种挥发性有机化合物（VOC）的三种二元混合物的平衡、穿透曲线和穿透时间，该模型结合了质量平衡、用于描述动力学的简单线性驱动力（LDF）假设以及著名的扩展朗缪尔（EL）平衡模型。该模型旨在以有限的复杂度，根据从单一组分获得的平衡和动力学数据预测暴露于二元蒸汽混合物的呼吸防护滤罐的穿透曲线。在该模型中，多组分传质被简化为仅使用单一动态吸附数据。本研究中使用的EL表达式对丙酮/乙醇和乙醇/环己烷混合物的平衡预测具有相对较高的准确性，但环己烷与庚烷混合时对其吸附量的预测不太令人满意。将模型给出的穿透曲线与实验穿透曲线进行比较，以确定模型的准确性以及近似对传质系数的影响。从穿透曲线确定暴露浓度10%时的穿透时间t10%。所有t10%的预测值与实验值的偏差在20%以内，63%的穿透时间预测误差在10%以内。本研究表明，简单的质量平衡与动力学近似相结合足以预测暴露于VOC混合物的呼吸防护滤罐的使用寿命。研究还表明，一种基于VOC挥发性而非吸附平衡来描述多组分吸附的常用方法大大高估了穿透时间。
