Patent GB-718714-A (GB)
Title: Lubricating oil compositions
IPC: C10M159/12
Filed: 1951-08-16
Abstract: Calcium mahogany sulphonate is prepared from crude sodium mahogany sulphonate by blending the crude sodium sulphonate with mineral oil and petroleum thinners, washing the blend with dilute aqueous sodium chloride to remove sodium sulphate and then emulsifying with aqueous calcium chloride.  Inorganic salts are removed from the oil phase by water washes and the thinners and the water are removed by heating at reduced pressure.  The product is a mineral oil solution of calcium mahogany sulphonate.  Calcium dialkyl benzene sulphonate is prepared from a dialkyl benzene obtained by alkylating benzene with polypropylene of molecular weight of about 170, using hydrofluoric acid as alkylating catalyst.  The dialkyl benzene is sulphonated with fuming sulphuric acid and the sulphonated material neutralized with aqueous caustic soda.  The crude sodium dialkyl benzene sulphonate is converted to a mineral oil solution of the corresponding calcium sulphonate using the procedure employed above for calcium mahogany sulphonate.ALSO:A stable dispersion of lead, magnesium or alkaline earth metal oxides or hydroxides in lubricating oil is prepared by forming a mixture of the lubricating oil, a dihydric alcohol having less than 6 carbon atoms in the molecule, the oxide or hydroxide and a polyvalent metal sulphonate, phosphonate or naphthenate.  The dispersion may be employed as the lubricant in an internal combustion engine and any acid formed by oxidation of the lubricating oil during operation of the engine is neutralized by the oxide or hydroxide. Lubricating oils mentioned are mineral oils, other hydrocarbon oils such as those derived from coal and alkylene polymers and other synthetic oils.  Synthetic lubricating oils referred to include alkylene oxide polymers and their esters and ethers, esters of dicarboxylic acids, esters of phosphoric acid and esters of phosphonic acids.  Suitable dihydric alcohols containing less than 6 carbon atoms in the molecule are ethylene glycol, propylene glycol, butane diol-2, 3, pentane diol-2, 4, 2-methyl butane diol-1, 2, 2-methyl butane diol-2, 4 and 2-methyl butane diol-3, 4.  Subsequent to the formation of the dispersion, however, the dihydric alcohol may be removed by distilling. Specified polyvalent metal suphonates are calcium and magnesium white oil benzene sulphonates (prepared from sulphonic acids obtained by alkylating benzene with chlorinated white oil and then sulphonating), calcium and magnesium dipolypropene benzene sulphonates (prepared from sulphonic acids obtained by dialkylating benzene with polypropene so that the alkyl radicles introduced in the benzene molecule have an average of 14 carbon atoms and then sulphonating), calcium and magnesium mahogany sulphonate, calcium and magnesium triacontyl sulphonate, and calcium and magnesium lauryl sulphonate.  Specified polyvalent metal naphthenates are the Ca, Ba, Zn, Pb, Sr. Mg, Mn and Cu salts of petroleum naphthenic acids.  A dispersion of the oxide or hydroxide in the alcohol may first be prepared and this dipersion then added to a blend of the lubricating oil and the sulphonate, phosphonate or naphthenate.  The lubricating oil compositions may contain additional ingredients such as oxidation inhibitors, pour point depressants, corrosion inhibitors, oiliness agents, extreme pressure agents, blooming agents, viscosity index improvers, grease-forming agents and other dispersants.  Oxidation inhibitors mentioned are organic esters of phosphous (e.g. calcium or zinc cetyphenyl dithiophosphate), metal salts of thiocarbamic acids (e.g. zinc dibutyl dithiocarbamate), sulphides (e.g. sulphurized diparaffin sulphide, sulphurized olefins and P2S5-pinene reaction products), and amines (e.g. phenyl alpha naphthylamine, 1, 4-diamino 2-dodecyl anthraquinone and p, p1-dioctyl diphenyl amine).  In the examples lubricating compositions are described consisting of mineral lubricating oil, calcium oxide, ethylene glycol and calcium naphthenate or calcium mahogany sulphonate, the ethylene glycol is some cases being removed by distilling subsequently to the formation of the dispersion.  In a further example, a lubricating composition comprises mineral lubricating oil, sulphurized diparaffin sulphide (the paraffin radicle being derived from a petroleum wax, sulphurized calcium phenate, zinc cetyl phenyl dithiophosphate, calcium mahogany sulphonate and calcium oxide (which has been dispersed in the oil, according to the procedure set out above, with the aid of the calcium mahogany sulphonate). Tests are described in which this lubricating composition of the example is compared with a similar composition from which the calcium oxide has been omitted.  Specification 648,328, [Group IV (b)], is referred to.