Patent GB-733839-A (GB)
Title: Lubricating oil composition
IPC: C07C303/32
Filed: 1953-08-04
Abstract: Organic solutions of complex metal salts are obtained by the following steps:-(1) contacting a solution in a hydrocarbon or mineral oil of an organic sulphonic acid or salt thereof in the presence of water with (a) at least 1.6 equivalents of metal hydroxide or carbonate; (b) at least 0.6 equivalent of metal formate; and (c) at least 0.6 equivalent of a metal carboxylate having 2-20 carbon atoms (the metals being of Group I or II and the equivalents being based on the active hydrogen in the sulphonic acid solution); (2) dehydrating the resulting mixture; and (3) filtering off insoluble material.  The metal formate and carboxylate may be supplied as free acid with consequent equivalent increase in the amount of metal hydroxide used. Preferably an aqueous slurry of the constituents (a), (b) and (c) is contacted with a mineral oil solution of the sulphonic acid at 25-100 DEG  C. to give a 20-60 per cent solution.  The components may be mixed in any order.  The dehydration step (2) is stated to cause the formation of a ternary complex salt of greater oil-solubility than its constituents.  The sulphonic acid is preferably derived from an alkyl-benzene or -naphthalene, such as the petroleum sulphonic acids known as "Sour Oils" (an example of the preparation of which is given) or a wax-benzene sulphonic acid obtained by condensing chlorinated paraffin wax with benzene and sulphonating the product (details given).  Examples show the preparation of the following complex salts: (1) formate+acetate+sour oil sulphonate of calcium, magnesium, barium, strontium, zinc, potassium, calcium+magnesium, calcium+barium+magnesium, and calcium+barium+zinc; (2) formate+acetate+ wax-benzene sulphonate of calcium and of magnesium; (3) calcium salt of formic+sour oil sulphonic+propionic, heptylic, crotonic, glycollic, lactic, chloracetic, thioglycollic, aminoacetic, acetic+crotonic, heptylic+aminoacetic, and lactic+chloracetic acids. The carboxylic acid may in general be saturated or unsaturated and may contain hydroxy, halogen, amino, mercapto or phenyl substituents. Further acids specified are butyric, valeric, caproic, lauric, myristic, palmitic, stearic, acrylic, oleic and phenylacetic.ALSO:Lubricating oils, particularly mineral lubricating oil fractions, contain as detergents complex metal salts derived from one or more metals of Group I or II and formic acid plus an organic sulphonic acid plus one or more carboxylic acids other than formic. Such a complex prepared in the presence of water and a mineral oil and subsequently dehydrated is stated to have a greater oil-solubility than its constituents.  The sulphonic acid is preferably derived from an alkyl-benzene or -naphthalene (e.g. the petroleum sulphonic acids known as Sour Oils, or sulphonated wax-substituted benzenes).  Specified metals are calcium, magnesium, barium, strontium, zinc, potassium, calcium plus magnesium, calcium plus barium plus magnesium, and calcium plus barium plus zinc. Specified carboxylic acids are acetic, propionic, butyric, valeric, hexoic, heptylic, lauric, myristic, palmitic, stearic, acrylic, crotonic, oleic, phenylacetic, glycollic, lactic, chloracetic, thioglycollic, aminoacetic, acetic plus crotonic, heptylic plus aminoacetic, and lactic plus chloracetic.  The lubricating oils may also contain anti-oxidants, extreme pressure agents, pour point depressants, viscosity index improvers and defoamants.