2558.     PADOVANI, C., AND GIORDANO, I.  [Production of Gas With High Hydrogen and Low Carbon Monoxide Contents by the Action of Steam on Carbon.]  Acqua e Gas, vol. 9, 1931, pp. 65-81; chim. et ind., vol. 26, 1931, p. 1064; Chem. Abs., vol. 26, 1932, p. 1417.

        Theoretically, the reaction of the production of H₂ is C+2H₂O=CO₂+2H₂-19 cal.; but, in practice, the process is carried out in 2 stages according to C+H₂O=CO+H₂-29 cal. and CO+H₂+H₂O=CO₂+2H₂+10 cal., the second stage being carried out at 400°-500° in presence of a catalyst.  From a theoretical application of the law of mass action to the equilibria CO₂+C=2CO and CO+H₂O=CO₂+H₂ and a study of the ratios CO:H₂ and (H₂O+H₂):H₂ (the 1^st measuring the impurity of the H₂ produced and the 2d the excess of undecomposed steam), considerable divergence was found between theoretical results and those obtained in practice, which is attributed to the thickness and nature of the layer of coke and to the treatment to which it was subjected during the coking process.  Methods also were studied of increasing the reactivity of the C:  (1) By addition of catalysts (chiefly alkali or alkaline earth salts, or oxides of Fe, Cr, or Mn); (2) by using coke (or more exactly semicoke) prepared under special carbonization conditions.  The experimental set-up used in the investigation is described.