Azzan Hassan, Rajagopalan Ashwin Kumar, L'Hermitte Anouk, Pini Ronny, Petit Camille
Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom.
Department of Materials, Imperial College London, London SW7 2AZ, United Kingdom.
Chem Mater. 2022 Aug 9;34(15):6671-6686. doi: 10.1021/acs.chemmater.2c01567. Epub 2022 Jul 27.
Shaped adsorbents (e.g., pellets, extrudates) are typically employed in several gas separation and sensing applications. The performance of these adsorbents is dictated by two key factors, their adsorption equilibrium capacity and kinetics. Often, adsorption equilibrium and textural properties are reported for materials. Adsorption kinetics are seldom presented due to the challenges associated with measuring them. The overarching goal of this work is to develop an approach to characterize the adsorption properties of individual shaped adsorbents with less than 100 mg of material. To this aim, we have developed an experimental dynamic sorption setup and complemented it with mathematical models, to describe the mass transport in the system. We embed these models into a derivative-free optimizer to predict model parameters for adsorption equilibrium and kinetics. We evaluate and independently validate the performance of our approach on three adsorbents that exhibit differences in their chemistry, synthesis, formulation, and textural properties. Further, we test the robustness of our mathematical framework using a digital twin. We show that the framework can rapidly (i.e., in a few hours) and quantitatively characterize adsorption properties at a milligram scale, making it suitable for the screening of novel porous materials.
成型吸附剂（如颗粒、挤出物）通常用于多种气体分离和传感应用中。这些吸附剂的性能取决于两个关键因素，即它们的吸附平衡容量和动力学。通常，会报告材料的吸附平衡和结构性质。由于测量吸附动力学存在挑战，因此很少呈现相关内容。这项工作的总体目标是开发一种方法，以表征材料少于100毫克的单个成型吸附剂的吸附特性。为此，我们开发了一种实验动态吸附装置，并用数学模型对其进行补充，以描述系统中的质量传输。我们将这些模型嵌入到无导数优化器中，以预测吸附平衡和动力学的模型参数。我们在三种化学性质、合成方法、配方和结构性质存在差异的吸附剂上评估并独立验证了我们方法的性能。此外，我们使用数字孪生测试了我们数学框架的稳健性。我们表明，该框架能够在几小时内快速且定量地表征毫克级别的吸附特性，使其适用于新型多孔材料的筛选。
