GB865411A - Process for the productionof heavy water - Google Patents

Abstract

In the production of heavy water by catalytic deuterium exchange between hydrogen and water in a dual-temperature system the catalyst is nickel, iron, or cobalt in the Raney form. Caustic alkali may be dissolved in the water. The catalysts in the Raney form are prepared by alloying the metal with Al, Zn or Mg and completely or partially dissolving out the alloying metal with caustic alkali. The catalysts may be the double-skeleton material described in Specification 806,644 prepared by compressing a mixture of metal carrier and the alloy, sintering the compressed body, and treating with caustic alkali. The catalyst may be granules which may be used as a stationary bed suspended in the H2O. Alternatively, the catalyst may be shaped bodies disposed in the reactors. The caustic alkali may be KOH in a concentration 0.001 N to saturation, preferably 0.05-2 N. Pairs of towers may be connected in a cascade with hydrogen flowing in closed cycle through each pair of towers, except the first, while some of the water flowing in countercurrent is withdrawn between the towers of a pair and passed to the next pair, whence water is returned to a point having the same D concentration. The towers work at 1-150, preferably 10-30 kg/sq.cm. with temperatures, in the cold towers 20-100 DEG , preferably 40-80 DEG C., and in the hot towers 100-250 DEG , preferably 160-200 DEG C. The D is fed to the cascade either by feeding fresh H2 to the first pair of towers, or by contacting the H2, flowing in closed cycle through the first pair of towers, with raw H2O in a separate tower.