THEORETICAL INTERPRETATION OF ADSORPTION BEHAVIOR OF SIMPLE FLUIDS IN SLIT PORES
THEORETICAL INTERPRETATION OF ADSORPTION BEHAVIOR OF SIMPLE FLUIDS IN SLIT PORES
复制标题
DOI：
10.1021/la00031a031
复制
发表时间：
1993-07-01
期刊：
影响因子：
3.9
通讯作者：
GUBBINS, KE
中科院分区：
文献类型：
--
作者：
BALBUENA, PB;GUBBINS, KE
用非局域密度泛函理论对简单流体在模型材料中的吸附行为进行了解释和分类。系统地研究了各种变量：温度、压力、孔宽H以及分子间参数比epsilon(Sf)/epsilon(Ff)和sigma(Sf)/sigma(Ff)。计算了吸附等温线、吸附等温热和相图。这些等温线与1985年IUPAC分类的等温线相关；确定了六种等温线类型对应的变量范围，并阐明了导致每种类型的潜在因素。除了1985年分类的六种类型外，还确定了第七种类型，对应于毛细蒸发。对孔道中的吸附和相变(毛细管冷凝和分层转变)的热也有类似的研究和分类。由于所研究的材料既没有表现出异质性，也没有表现出网络，所以可以清楚地看到导致相变的条件。在可能的情况下，与实验观测进行定性比较。这里报告的理论分类应该提供一个有用的框架来解释实验数据。
Nonlocal density functional theory is used to interpret and classify the adsorption behavior of simple fluids in model materials having slit pores. A systematic study is reported for a wide range of the variables involved: temperature, pressure, pore width H, and the intermolecular parameter ratios epsilon(sf)/epsilon(ff) and sigma(sf)/sigma(ff). Adsorption isotherms, isosteric heats of adsorption, and phase diagrams are calculated. The isotherms are related to those of the 1985 IUPAC classification; the range of variables corresponding to each of the six isotherm types is determined, and the underlying factors leading to each of the types are elucidated. In addition to the six types of the 1985 classification, a seventh type is identified, corresponding to capillary evaporation. A similar study and classification is reported for the heats of adsorption and phase transitions (capillary condensation and layering transitions) in pores. Since the materials studied do not exhibit either heterogeneity or networking, the conditions leading to phase transitions are clearly seen. Where possible, qualitative comparisons with experimental observations are made. The theoretical classification reported here should provide a useful framework against which to interpret experimental data.