Methods of controlling the rates of release of chemical additives into treating fluids are provided by the present invention. The methods are basically comprised of causing a chemical additive in liquid form to be absorbed into a porous solid material whereby the chemical additive is encapsulated thereby and when the resulting encapsulated chemical additive is combined with the treating fluid, the chemical additive is slowly released into the treating fluid. After being encapsulated, the liquid chemical additive is combined with the treating fluid and the treating fluid containing the encapsulated chemical additive is introduced into a well.