2536.     OSBORNE, R. M.  Adsorption of Low-Boiling Hydrocarbons by Activated Carbon.  FIAT Tech. Bull. T-34, May 1, 1947, 2 pp.

        Carboraffin, which is made from sawdust, activated by ZnCl₂, and powdered, is 1 of the several active carbons mentioned in FIAT Final Report 863, and manufactured by the I. G. Farbenindustrie, Leverkusen.  It is said to have good adsorptive capacities for low boiling hydrocarbons.  A carbon based upon the Carboraffin type with similar adsorption isotherms has now been developed into an active carbon capable of being fluidized and used in a continuous adsorption process.  The exact method of manufacture has not been disclosed. On an industrial scale, there have been no developments on the preparation of active carbons that show selectivity for chemical types of hydrocarbons, although on a laboratory scale, where the time factor is not essential, some work has been done.  It is almost certain that the presence of metals does not increase the selectivity of a given activated carbon for a particular type of hydrocarbon. Presents some of the physical properties and constants of active carbons developed by the Lurgi Co.