Energetic criteria for oxychlorination catalysts

The energetic criteria for oxychlorination catalysts are reduced under stated assumptions to energetic criteria associated with catalysts for the Deacon process. The analysis is mainly concerned with the standard free-energy changes as a function of temperature, associated with the reactions of metal chlorides with oxygen, and of metal oxychlorides and oxides with hydrogen chloride. Using the known catalytic activity of the copper(II) chloride/oxide catalyst pair as a guide, the possible value of other divalent, monovalent, trivalent and tetravalent chloride/oxide pairs alone and in combination is assessed energetically. The results are shown to explain a number of technological facts concerning active catalysts given in the patent literature.