【摘要】 用智能重量分析仪测定了环戊烷在Silicalite-1上的吸附等温线,根据吸附等温线数据计算了热力学参数(吸附热Qst、熵变ΔS、Gibbs自由能变ΔG)。423K时,吸附等温线符合Langmuir方程。254,274K时,吸附等温线出现了滞后环。与分子构型相近的苯与环己烷相比,环戊烷的饱和吸附量超乎寻常,Qst、ΔG、ΔS随吸附量的变化较大,表明环戊烷在Silicalite-1上的吸附机理相当复杂。在吸附过程中,吸附质分子之间、吸附质和Silicalite-1之间的相互作用较强,环戊烷分子发生了重排。当吸附量达到1.5mmol/g时,吸附相开始凝聚,吸附热逐渐达到了凝聚热值。更多还原

【Abstract】 The adsorption feature of cyclopentane in silicalite-1 was studied by using intelligent gravimetric analyzing technology. The thermodynamic parameter was calculated according to the data of absorption isotherm. The result shows that the shape of the isotherm changes from type I to type IV as temperature decreased. The isotherms at 254 and 274 K, at which pronounced loops can be detected, are type IV and at 423 K, are type I.The isotherm at 423 K, also, can well be derived from Langmuir equation. The heat of cyclopentane sorption vary significantly with the sorption coverage. During the absorption, the interactions among the sorbate-molecules are strong, so are the interactions between sorbates and silicalite-1, which lead to the arrangement of cyclopentane molecules. When the loading of cyclopentane on silicalite-1 get about 1.5 mmol/g, the heat of adsorption reaches the heat value of condensation.更多还原