PATENTS

3217.  RUTLEDGE, T.F., AND SEGER, F. M. (Socony Vacuum Oil Co., Inc.).  Method of Purifying a Lubricating Oil Feedstock With Zinc Halides.  United States Patent 2,622,094, Dec. 16, 1952; appl. filed Mar. 11, 1949, Serial No. 81,013; 3 claims (Cl. 260-450).

Synthetic lubricants of good color, high viscosity index and low C residues can be obtained by treating complex olefinic charge stock from Fischer-Tropsch reaction with Zn chloride.  The treated charge is distilled to remove any reaction products that may dissolve in the excess hydrocarbon present.  The distillate contains purified and concentrated olefins, particularly normal, alpha monoolefins.  The fraction b. 100°-600° F., predominantly 150°-500° F. is taken overhead.  Filtration of the charge before distillation will remove any occluded solid particles.  The distillate is converted to lubricant by heating 625° F. for 10 hr.11 United States patents cited.