Abstract: A gas chromatography apparatus adapted for large scale separation of gases at low temperature comprises a column packed with a solid adsorbent and having a cooling tube being open at both ends extending centrally through its length. The column is suspended in a pressure vessel so that it may be totally immersed in a liquified gas coolant. The pressure vessel has heating means to maintain the coolant at its boiling point and thereby to regulate the temperature within the vessel by varying the pressure therein. The apparatus has particular application to the large scale separation of hydrogen isotopes.

Abstract: A method for separating hydrogen isotope species by gas chromatography is described. The invention utilizes low temperature chromatography on molecular sieves with peak cutting or temperature programming depending on the particular application. The method provides a much larger throughput capability than was heretofore available. The invention also includes the separation of mixed dimer isotope species from the helium carrier gas by condensation, and storage thereof at low temperature in a non-catalytic environment so that equilibration may be avoided.

Abstract: In order to remove carbon dioxide from an off-gas stream and immobilize it in solid stable form, the gas is passed through a packed bed of calcium hydroxide maintained at a temperature in the range 10.degree. C.-50.degree. C., the moisture content of the gas being controlled so as to correspond to a relative humidity from 40% to 100% at the bed temperature.