PATENTS

      171.     BERG, C. H. O.  (Union Oil Co. of California).  Adsorption Process and Apparatus for Separating Gaseous Hydrocarbon Mixtures.  United States Patent 2,609,887, Sept. 9, 1952.  Chem. Abs., vol. 47, 1953, pp. 849-850.

Gaseous hydrocarbon mixtures are separated by passing a moving bed of solid granular absorbent through a vertical column consisting of a succession of individual adsorption and reflux zones; the rich absorbent thus formed is passed successively through a heating zone, a seal gas-removal zones, and a cooling zone immediately before being removed from the bottom of the column for reuse.  An example of the column operation is the fractionation, by absorption, of a cracked petroleum hydrocarbon gas, which was fed at 150 p. s. i. into a 12-ft.-diameter column at the rate of 2,141 lb.-moles per hr. by using 330,000 lb. of activated vegetable charcoal per hr.  The 4 fractions obtained consisted essentially of a H2-CH4 mixture, a pure C2 fraction of ethane and ethylene, a pure C3 fraction of propane and propylene, and a C4-rich fraction containing also C5 and higher hydrocarbons.