Generalized Isotherms for Mono- and Multicomponent Adsorption
To correlate gas adsorption equilibria data many different adsorption isotherms (AIs) are used in today’s literature [1, 2], To extend their range of applicability often characteristic exponents αi ≠ 1 of Freundlich type are introduced. However, in this case the limiting slope of the AI at low pressure is either infinite or zero, contrary to experimental data of adsorption equilibria indicating a finite nonzero slope. The object of this work is to overcome this difficulty by introducing pressure (and temperature) dependent exponents to ensure the existence of the classical Henry region. Using these exponents in the classical Langmuir-Freundlich AI, it is possible to correlate experimental adsorption data in a wide range of pressure and temperature. The temperature dependences of other parameters in a class of generalized Langmuir-Freundlich AIs is also discussed.
KeywordsAdsorption Isotherm Adsorption Energy Adsorption Equilibrium Characteristic Exponent Adsorption Equilibrium Data
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