GB790471A - Improvements in or relating to the preparation of polyvalent metal basic salts of organic acids in hydrocarbon oil solution - Google Patents

Abstract

Oil soluble polyvalent metal basic salts of certain organic acids, viz. sulphonic acids, carboxylic acids containing no sulphur atom in the molecule and phosphorus containing acids, are prepared by reacting a hydrocarbon oil solution of a polyvalent metal salt of the organic acid, the salt being soluble in mineral oils to the extent of at least 10 per cent by weight at room temperature, with a polyvalent metal carbonate, which is formed in situ in the reaction mixture, at a temperature between 65 DEG and 125 DEG C. and in the presence of at least 2 per cent of free water in the liquid state based on the weight of the oil solution. The metal carbonate is formed in situ by reaction of a polyvalent metal base with carbon dioxide or by a reaction involving the interaction of polyvalent metal ions and carbonate ions, for example, by reaction between a water-soluble polyvalent metal salt and an alkali-metal carbonate. The desired polyvalent metal basic salts are obtained as an oil solution from which they can be isolated by removal of the oil. The polyvalent metal organic acid salt used as starting material may itself be formed in situ by reacting the free acid with a polyvalent metal base or by reacting metathetically a different salt of the organic acid with a suitable compound of the polyvalent metal. The polyvalent metal organic acid salts used as starting materials may be neutral or basic and are preferably alkaline earth metal (including magnesium) salts. The amount of water to be present in the reaction mixture is preferably about 5 to 50 per cent by weight of the oil solution used. The reaction is preferably effected at between about 80 DEG and 100 DEG C.; at higher temperatures super-atmospheric pressures are required. The organic acids may be petroleum sulphonic acids, naphthene sulphonic acids, long chain aliphatic-substituted aromatic, heterocyclic or cycloaliphatic sulphonic acids, e.g. cetyl cyclo pentyl sulphonic acids, long chain aliphatic-substituted aromatic carboxylic acids such as alkyl salicyclic acids, other cyclic carboxylic acids such as petroleum naphthenic acids and di-lauryl decahydronaphthalene carboxylic acids, and tri- and pentavalent phosphorus acids and corresponding thiophosphorus acids such as organic phosphoric acid esters containing at least 12 carbon atoms and lauryl monothio phosphoric acid. In typical examples: (1) a mineral oil solution of calcium petroleum mahogany sulphonates is mixed with an aqueous slurry of Ca(OH)2 and is then maintained at 95 DEG C while CO2 is introduced therein and thereafter the solution is dried and filtered; the so formed solution of basic metal sulphonate may be retreated in the same manner one or more times with consequent increased basicity; instead of introducing the CO2 into the reaction mixture, the latter may be sprayed into a carbon dioxide atmosphere; (2) a mineral oil solution of neutral barium petroleum sulphonates is diluted with a lubricating oil fraction, mixed with barium hydroxide and water and then treated with CO2 at 95 DEG C.; (3) a mineral oil solution of sodium petroleum sulphonates, diluted with a lubricating oil, is mixed with calcium hydroxide, calcium chloride and water and then reacted with CO2 at 95 DEG C.; (4) a mineral oil solution of calcium C14-C22 alkyl salicylates is treated as in (1); (5) a mineral oil solution of calcium petroleum sulphonates is heated to 95 DEG C. and mixed with an aqueous solution of calcium chloride and thereafter, at the same temperature, an aqueous solution of sodium carbonate is slowly added and the resulting solution of basic calcium salts is then dried and filtered. Specification 744,942 is referred to.ALSO:Hydrocarbon oil solutions of polyvalent metal basic salts of sulphonic acids, carboxylic acids containing no sulphur atoms in the molecule and organic phosphorus containing acids are prepared by reacting a hydrocarbon oil solution of a polyvalent metal salt of the organic acid, the salt being soluble in mineral oils to the extent of at least 10 per cent by weight at room temperature, with a polyvalent metal carbonate formed in situ in the reaction mixture, at a temperature between 65 DEG and 125 DEG C. and in the presence of at least 2 per cent of free water in the liquid state based on the weight of the oil solution (see also Group IV (b)). The metal carbonate is formed in situ by reaction of a polyvalent metal base with carbon dioxide or by a reaction involving the interaction of polyvalent metal ions and carbonate ions, e.g. a reaction between a water-soluble polyvalent metal salt and an alkali metal carbonate. The polyvalent metal organic acid salt used as starting material may itself be formed in situ from the free organic acid or a different salt such as an alkali metal salt thereof, in a specified manner, and may be neutral or basic. The polyvalent metal basic salts may be isolated from their hydrocarbon oil solutions by removal of the oil and can then be dissolved in a lubricating oil. The salts are preferably alkaline earth metal and magnesium salts. Examples describe the preparation of solutions in mineral oil, admixed or not with a lubricating oil, of basic calcium or barium petroleum (mahogany) sulphonates and of basic calcium salts of C14-C22 alkyl salicylic acids. The salts may also be derived from long chain aliphatic substituted aromatic, heterocyclic or cyclo aliphatic sulphonic acids, e.g. cetyl cyclopentyl sulphonic acids, petroleum naphthenic acids, di-lauryl decahydro naphthalene carboxylic acids, organic phosphoric acid esters containing at least 12 carbon atoms and lauryl mono-thiophosphoric acid. Specification 744,942 is referred to.