671113-A is referenced by 4 patents.
Waxes are refined by treating the molten wax with 5-25 per cent, by weight of the crude wax, of a solid adsorbent to form a dry pulverulent mixture, extracting this mixture with a solvent for the wax, and recovering the wax from the solution. Waxes treated are animal, vegetable or mineral waxes or artificial waxes obtained from the distillation of petroleum or from the destructive distillation of paraffinaceous shales. Adsorbents specified are fuller's earth, active carbon, silica gel and alumina gel. Petroleum spirit and ether are mentioned as solvents. In a modification of the process the wax after mixture with the adsorbent is extracted first with a solvent for the impurities and then with a solvent for the wax. In an example, a crude petroleum wax (pipe wax) is heated to 115 DEG C and added to 15-20 per cent of its weight of Fuller's earth.; The mixture is stirred and then extracted with 1-4 times (on the weight of the wax) of petroleum spirit. The wax solution is concentrated by evaporation and the wax crystallized out. This refining process is repeated twice and the wax is finally treated with a mixture of fuller's earth and activated carbon and extracted as above. The purification of raw beeswax is also described. Specification 354,775 is referred to.