Activated carbon adsorption can be divided into physical adsorption and chemical adsorption according to different principles. Physical adsorption is caused by the van der Waals force between molecules. Since the molecules of solid surface are different from the internal molecules, there is a remaining surface free force field. When the gas molecules move to the vicinity of the solid surface, they will be attracted and stay on the solid surface, while the activated carbon is a porous material, and the complex pore structure greatly increases the surface area of the solid, and the surface energy is significantly enhanced, so that the adsorption capacity of the material is remarkably improved. Chemical adsorption is caused by chemical bond forces. When a chemical reaction occurs on a solid surface, the chemical reaction changes the electron orbit mode of the adsorbed molecule, so it is difficult to restore to the original species and It is an irreversible process.
Activated carbon flue gas desulfurization method is a simultaneous process of physical adsorption and chemical adsorption. There are a series of chemical reactions on the surface of activated carbon. However, due to the complexity of the surface of activated carbon, there are many kinds of principles for desulfurization of activated carbon, including two main types. One believes that activated carbon can remove SO2 in the presence of O2 and a small amount of water vapor. The other one is the ion exchange adsorption principle and the electrolayer adsorption principle.
