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Return to Abstracts of Patents Return to Abstracts of Patents 1000-1249 Patent Abstracts1211. ------. [I. G. FARBENINDUSTRIE A. G.] Cooking Gases. British Patent 474,191, Oct. 27, 1937. Chem. Abs., vol. 32, 1938, p. 2792. Hot gases or vapors are cooled by injecting a liquid of a different chemical nature, preferably H2O, in a finely divided state at a temperature that is (a) equal to or > its boiling point at the pressure of the gases to be cooled and (b) < the temperature of the gases. The complete evaporation of the injected H2O thus insured is useful in process; for example, obtaining gases by roasting pyrites, where the presence of liquid H2O is deleterious to the constructional materials of the apparatus. The invention is applicable to exothermic catalytic reactions in which the main part of the gases involved in converted by means of a 1st contact layer, the final conversion being effected by means of a 3d contact layer, and the gases being cooled between the 2 stages. Such processes are used, for example, for producing H2 and CO from hydrocarbons and steam; for the oxidizing SO2; in the synthesis of NH3 from N2 and H2, liquefied NH3 being preferably injected in this case between the contact layers for cooling the gas; or in the synthesis of hydrocarbons from CO and H2, superheated hydrocarbons being injected between 2 or more contact layers. The invention is also useful when products formed are to be prevented from decomposing of oxides of N by combustion of NH3 and in the production of unsaturated hydrocarbons by thermal decomposition. |