Temkin and Freundlich Isotherms

Question 1

Define Temkin

Answer 1

non equivalent/ non independent sites; when adsorption enthalpy changes linearly with p
=>based on linearly changing distribution of site energies
=>only valid for limited pressure range
=>fails at higher pressures

Question 2

Define Freundlich

Answer 2

non equivalent/ non independent sites; when adsorption enthalpy changes logarithmically with p
=>exponential distribution of site energies
=>doesn’t obey henrys law at low pressures
=>doesn’t reach maximum adsorption at high pressure

Question 3

Define C1 from the equation

Answer 3

C1 is characteristic constant, defines adsorption magnitude driving force

Question 4

Define C2 from the equation

Answer 4

C2 is heterogeneity parameter, relates adsorption affinity between adsorbate and adsorbent