L11 Adsorption and transport

Key difference between fluid and solid interfaces

Solid interfaces are much sharper - molecules from the solid do not ‘leak into’ the other phase and vice versa.

There are well-defined adsorption sites

Chemisorption and physisorption at interfaces

Adsorption isotherms – Langmuir isotherm

Langmuir isotherm, Free Energy of Adsorption

Increasing the free energy of adsorption naturally increases the occupancy of adsorption sites

Isosteric Enthalpy of adsorption

Empirical models of adsorption

Enthalpy of adsorption becomes less negative as adsorption increases

BET isotherm - what is the additional factor included

Includes the possibility that we form multiple layers of adsorbate

BET isotherm adsorption graph

Factors affecting the rate at which equilibrium is reached

What is advection

Laminar vs turbulent flow

Mass transport as part of the reaction equation for interfaces

Flow type next to the solid and the stagnant layer components