基于分子动力学理论的碳捕集用吸附剂选择与实验研究

Selection and experimental study of adsorbents for carbon capture based on molecular dynamics theory

选择13X、NaY、MCM-41、NaA和CaA 5种代表性的沸石材料分别建立了分子模型,利用大正则蒙特卡罗(GCMC)模拟研究了该5种沸石材料分别对纯CO_(2)和N_(2)的吸附分离行为,获得了单组分等温曲线和等容吸附热曲线,以此揭示不同沸石材料的吸附机理。结果表明,NaY在室温下对纯CO_(2)的饱和吸附量最高(6.14 mmol/g);在对CO_(2)/N_(2)混合气体选择性吸附的研究中发现,CaA与CO_(2)的结合力最强,NaY对CO_(2)选择性最高。该模拟计算有助于吸附法CO_(2)捕集中沸石骨架材料的筛选,并为后续实验研究提供理论依据。

Five representative zeolite materials,13X,NaY,MCM-41,NaA and CaA,were selected to establish molecular models.The adsorption and separation behaviors of pure CO_(2)and N_(2)on the five zeolite materials were studied by Grand Canonical Monte Carlo(GCMC)simulation.The single component isotherm curve and isometric adsorption heat curve were obtained to reveal the adsorption mechanism of different zeolite materials.The results showed that NaY had the highest saturated adsorption capacity for pure CO_(2)(6.14mmol/g)at room temperature.In the study of selective adsorption of CO_(2)/N_(2)mixed gas,CaA had the strongest binding force with CO_(2),and NaY had the highest selectivity for CO_(2).The simulation calculation was helpful for the screening of zeolite framework materials for CO_(2)capture by adsorption method.This simulation calculation provided a theoretical basis for subsequent experimental research.