(under subclass 177) Processes for treating used mineral oils to render them suitable for reuse.
(1) Note. Many of the processes classified in this or indented subclasses are directed to the treatment of mineral oil dry cleaning solvents or lubricating oils.
SEE OR SEARCH THIS CLASS, SUBCLASS:
187, through 307, for similar processes of refining other mineral oils.
SEE OR SEARCH CLASS
123, Internal-Combustion Engines,
196, for purifiers contained in the lubricating systems peculiar to internal-combustion engines. 184, Lubrication, appropriate subclasses for lubricating systems that include a filter for the lubricating oil.
210, Liquid Purification or Separation, for liquid purification not otherwise provided for, see particularly
234+, 296 and 511 for the use of liquid as separating medium; subclasses 737, 766, and 774+ for process of separating including heating or cooling; and subclasses 175+ for separators combined with heaters or coolers.
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.
