Adsorption Isotherms from Two-Dimensional Equations of State

Adsorption Isotherms from Two-Dimensional Equations of State 

Numerous types of equations of state apply to solids, liquids, and gases a few of these are considered here. 

Ideal-Gas Law. Here Eq. XVII-67 applies, and on reversing the procedure that led to it, one finds 

The ideal gas law equation of state thus leads to a linear or Henry s law isotherm. A natural modification adds a co-area term  

Equation XVII-70 bears a strong resemblance to the Langmuir equation (see Ref. 4)—to the point that it is doubtful whether the two could always be distinguished experimentally. An equivalent form obtained by Volmer [53] worked well for data on the adsorption of various organic vapors on mercury [54] (see Problem XVII-40). 

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B. Adsorption Isotherms from Two-Dimensional Equations of State... 

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