Patent GB-802164-A (GB)
Title: Improvements in or relating to the preparation of oil-soluble metal sulfonates
IPC: C07F9/04
Filed: 1955-08-02
Abstract: Detergents for use in lubricating oils are prepared by sulphonating neutral, mineral oilsoluble metal salts of polyolefine-phosphorus pentasulphide condensation products and treating the acidic metal salts formed with mineral oil-insoluble basically reacting compounds (see Group IV (b)).  The products may be neutral or basic, the latter optionally being treated with an acidic gas such as carbon dioxide, sulphur dioxide or hydrogen sulphide, optionally in the presence of phenols, enols, alcohols or aci-nitro compounds.  In an example a composition for addition to engine oil is prepared by heating the product obtained by sulphonating the barium salt of a polyisobutylene-phosphorus pentasulphide condensation product, a di-isobutylphenol-formaldehyde condensation product, barium oxide, mineral lubricating oil and water.ALSO:A process of preparing oil-soluble metal sulphonates comprises the reaction of a neutral oil-soluble metal salt of a polyolefin-phosphorus pentasulphide condensation product with a sulphonating agent to form an acidic metal salt and subsequent treatment of said acidic metal salt with an oil insoluble basically reacting metal compound.  The terms "oil-soluble" and "oil-insoluble" are defined as meaning soluble in mineral oil and insoluble in mineral oil respectively.  Suitable polyolefin-phosphorus penta-sulphide condensation product from which salts for use as starting materials may be prepared are described in U.S.A. Specifications 2,316,078, 2,316,091, 2,367,468, 2,375,315, 2,377,955, 2,496,508, 2,507,731, 2,597,750 and 2,647,889 and the products may be treated before or after neutralization with steam. The metal constituent of the oil-soluble metal salts may be selected from mono- and polyvalent metals, e.g. alkali- and alkaline earth metals, and magnesium. Specific salts mentioned include the sodium salt of a steam-treated phosphosulphurized polyisobutylene and lithium and barium salts of phosphosulphurized polyisobutylene. Sulphonating agents mentioned include oleum, concentrated sulphuric acid, sulphur trioxide, chlorsulphonic acid and complexes of sulphur trioxide.  The acidic metallic salts obtained intermediately may be converted to the normal metal salts or basic metal salts, more than the stoichiometric proportion of the oil-insoluble basically reacting metal compound being employed to produce the latter. Basically reacting metal compounds mentioned include oxides, hydroxides, carbonates and lower molecular weight alcoholates, e.g. methylates and butylates.  The basic metal salts may be treated with an acidic gas such as carbon dioxide, sulphur dioxide or hydrogen sulphide, e.g. in the presence of phenols, enols, alcohols or aci-nitrocompounds, preferably in the presence of phenolic materials having an ionization constant in water of at least 1 X 10-10 at 25 DEG  C., a water solubility of at least 0.0005 per cent at 50 DEG  C. and a pH of less than 7 in a saturated aqueous solution at 25 DEG  C. In an example an oil-soluble liquid is obtained by heating a mixture of polyisobutylene having an average molecular weight of 750 and phosphorus pentasulphide, neutralizing the product with barium oxide, heating the product with chlorsulphonic acid under nitrogen, adding a diisobutylphenol formaldehyde condensation product obtained by reacting diisobutylphenol with formaldehyde in the presence of ammonium hydroxide, barium oxide, mineral oil and water and again heating and filtering.  The products are employed as lubricating oil additives.