Patent GB-800693-A (GB)
Title: Pour point depressant for lubricating oils
Inventor: BAKER EDWIN RUGGLES
Filed: 1955-07-15
Abstract: Compounds suitable as lubricating oil pour point depressants are prepared by reacting 1 mol. of chloromethylated synthetic still bottoms (a highly refractory petroleum fraction consisting of the bottoms from the distillation of the product resulting from the moving bed catalytic cracking of petroleum oils) with 0.25 to 1 mol. of an alkylaryl hydrocarbon having a side chain of at least 12 carbon atoms, at a temperature of 20-30 DEG  C. for 5-12 hours, in the presence of a Friedel-Crafts catalyst, and preferably in the presence of an inert organic solvent such as kerosene or Stoddard Solvent.  In an example, a mixture of diwaxbenzene, anhydrous aluminium chloride and Stoddard Solvent were stirred in a reaction vessel whilst chloromethylated synthetic tower bottoms was introduced drop-wise over an hour, the mixture reutralized with aqueous caustic soda and allowed to separate.  The pour point depressant was obtained as a residue upon removal of the Stoddard Solvent from the hydrocarbon layer.  When added to a waxy lubricating oil, e.g. Pennsylvania type, having a high pour point, the blend will have a substantially lower pour point.  A small amount of the compound may be used to remove wax from lubricating oils having a high wax content, or may be used in paraffin wax or paraffin wax composition for impregnating paper or making moulded products.ALSO:Compounds suitable as lubricating oil pour-point depressants are prepared by reacting 1 mol. of chloromethylated synthetic still bottoms (a highly refractory petroleum fraction consisting of the bottoms from the distillation of the product resulting from the moving bed catalytic cracking of petroleum oils) with 0.25 to 1 mol. of an alkylaryl hydrocarbon having a side chain of at least 12 carbon atoms, at a temperature of 20-30 DEG  C. for 5-12 hours, in the presence of a Friedel-Craft's catalyst, and preferably in the presence of an inert organic solvent such as kerosene or Stoddard Solvent.  The reaction mixture is neutralized with an aqueous solution of a base such as caustic alkali and the pour depressant recovered from the upper layer of the separated mixture.  Friedel-Craft's catalysts referred to are aluminium, zinc and ferric chlorides, titanium tetrachloride, boron trifluoride and anhydrous hydrogen fluoride.  Alkylaryl hydrocarbons referred to are waxbenzene, waxtoluene, diwaxbenzene, diwaxtoluene, polywaxbenzene, polywaxtoluene, waxnaphthalene, diwaxnaphthalene, polywaxnaphthalene, a propylene polymer having a boiling range of 175-250 DEG  C. and a mixture of monalkylbenzenes and dialkylbenzenes.  Inert solvents referred to are refined kerosine and Stoddard Solvent.  In an example, a mixture of diwaxbenzene, anhydrous aluminium chloride and Stoddard Solvent were stirred in a reaction vessel whilst chloromethylated synthetic tower bottoms was introduced drop-wise over an hour. The temperature was maintained at 27-30 DEG  C. for six hours, the mixture neutralized with aqueous caustic soda and allowed to separate.  The pour-point depressant was obtained as a residue upon removal of the Stoddard Solvent from the hydrocarbon layer.