超临界氢在活性炭上的吸附等温线研究

通过７７－２９８Ｋ范围内氢在ＡＸ－２１活性炭上的吸附数据，探讨如何用普通Ｉ－型等温线模型处理超临界条件下的吸附等温线，以获取关于超临界吸附系统的正确信息，结果表明，Ｌａｎｇｍｕｉｒ方程虽然可用来表达实验数据，但不能提供关于该吸附系统的任何可靠信息，Ｖｉｒｉａｌ方程虽不是整组数据的最好模型，但却能够可靠地确定Ｈｅｎｒｙ定律常数，然后可从ｖａｎｔＨｏｆｆ标绘决定等量吸附热，通过将实验数据拟合到Ｄｕｂｉ

Study on the Adsorption Isotherms of Supercritical Hydrogen on Activated Carbon

The aim of this paper is to study how to treat the experimental adsorption isotherms by the conventional Type－I isotherm theories in order to acquire the required information of the adsorption system under supercritical conditions. The study was carried out on manipulation of a set of adsorption data of supercritical hydrogen on activated carbon AX－21 over a temperature range of 77－298K. The results show that the Langmuir equation can well model the experimental data, but cannot provide any reliable information about the adsorption system considered; the Virial equation cannot model the whole set of data satisfactorily, but it can give Henry's law constants reliably， from which isosteric heat of adsorption can then be precisely determined. Some inspection of the adsorption mechanism was made on fitting data to Dubinin-Astakhov equation. Although this equation can best model the experimental data, the reality of any physical quantity evaluated from it might be doubtful since the parameters in the model interact each other during regression and some quantities in the equation are ill－defined under supercritical condition.