3.Adsorption isothermal equations (1)Langmuir equation (1916) Basic assumptions: (a)Adsorption is monolayer (b)The surface of solid is uniform. (c)There is not interacting force among the molecules adsorbed. 3. Adsorption isothermal equations (1) Langmuir equation (1916) (a) Adsorption is monolayer. (b) The surface of solid is uniform. (c) There is not interacting force among the molecules adsorbed. Basic assumptions: