Henry范围内粗糙孔隙中气体的等量吸附热与吸附选择性

Isosteric heat and selectivity in adsorption of gases in rough pores:In Henry’s law region

Henry系数和等量吸附热是表征气体吸附中气-固作用的重要参数.为了更好地理解气体在粗糙孔隙中的吸附特征,首先构造并计算了矩形波纹粗糙狭缝及其外势分布.进一步,采用经典统计力学研究了狭缝中H_(2)分子在低压范围内的纵向Henry系数和等量吸附热.研究结果表明,粗糙狭缝的几何形貌和基板间距等因素可对狭缝中气体的纵向Henry系数和等量吸附热产生显著的影响与调制作用.进一步,在Henry范围内计算了CO_(2)/H_(2)二元混合物气体在矩形波纹粗糙狭缝中的吸附选择性,并研究了狭缝几何形貌的调制作用.此外,还研究了不同形状的凸起对气体吸附性质的影响.相关的结果可为理解多孔材料中气体的吸附、分离和提纯等过程提供可靠的理论依据,并有望为设计与研发新型纳米功能材料提供有益的参考.

Henry constant and isosteric heat of adsorption are important parameters for characterizing the gas-solid interaction in an adsorption process.In order to better understand the adsorption behavior of gas in rough pores,we construct rough slit pores by using two rectangular corrugated substrates,and then calculate the potential profile in it.By utilizing classical statistical mechanics,the longitudinal Henry constant and isosteric heat of H_(2) are further calculated in the Henry region.The results suggest that both geometric morphology and pore width can significantly influence and modulate the longitudinal Henry constant and isosteric heat of the gas in the pore.Furthermore,the selectivity of adsorption in the binary CO_(2)/H_(2) mixture is also calculated and investigated in the Henry region.In addition,the effects of corrugated substrates with different geometries on adsorption properties are also calculated and studied.The result can provide reliable theoretical basis for understanding the adsorption,separation and purification of the gas in porous materials,and it is also expected to provide helpful idea for designing and exploring new nano functional materials.