Chlorine is an important reactant in industrial synthesis of organic polymers and solvents. This halogen also serves an important role in the promising processes of chlorine metallurgy. Hydrogen chloride is a common by-product in these processes, and recovery of chlorine from this waste is an important problem. The most attractive approach to this problem is catalytic oxidation of hydrogen chloride by oxygen (known as the Deacon process) since it allows to decrease electrical energy consumption by an order of magnitude, compared to electrolytic methods commonly used for this waste material processing. This book presents a study of hydrogen chloride oxidation over catalysts based on vanadium(V) oxide, use of which for said purpose is practically unresearched. Activity and stability of the studied catalysts considerably exceed the corresponding results given in any published data. The maximum obtained productivity values are greater than those of all known Deacon reaction catalysts, except for ruthenium catalysts. This book also contains a literature review regarding the prominent industrial and experimental methods of chlorine production.