(under subclass 179) Processes in which a plurality of inorganic materials are added to the used oil, either together or in sequence.
SEE OR SEARCH CLASS
516, Colloid Systems and Wetting Agents; Subcombinations Thereof; Processes of Making, Stabilizing, Breaking, or Inhibiting,
113+, for compositions for or subcombination compositions for or breaking of or inhibiting of colloid systems (e.g., foam breaking, emulsion breaking, dispersion inhibiting, suspension settling, gel breaking, smoke suppressing, coagulating, flocculating), when generically claimed or when there is no hierarchically superior provision in the USPC for the specifically claimed art. Combinations of emulsion breaking and a treatment of the mineral oil provided for in Class 208 are classified in Class 208.