Patent GB-780642-A (GB)
Title: Process for preparing basic polyvalent metal salts of organic acids
IPC: C10M159/20
Filed: 1955-12-28
Abstract: Basic polyvalent metal salts of organic sulphonic or carboxylic acids, which salts may be added to hydrocarbon oils such as lubricating oils and fuel oils, and may be used in the preparation of emulsions of water and oil, are made by adding an aqueous solution of an alkali metal hydroxide and an aqueous solution of an inorganic polyvalent metal salt to a solution of an organic sulphonic or carboxylic acid or a salt thereof (other than the alkali metal salt of an aromatic hydroxycarboxylic acid or mixture thereof with an alkali phenolate described in Specification 759,346) in an anhydrous solvent and removing the water from the reaction mixture by distillation under such conditions that only a part of the solvent is also distilled off. Acids specified are petroleum or alkylaromatic sulphonic acids and naphthenic acids.  Benzene, xylene and gasoline are specified as anhydrous solvents.  Alkaline earth, aluminium or chromium salts may be prepared by this process.  The basic salts may separate in part from the reaction product, as well as the neutral salts formed and these may be filtered or centrifuged off, followed by extraction of solid or solution e.g. with a light hydrocarbon oil. In examples, an aromatic extract obtained from kerosene with liquid sulphur dioxide is alkylated with a technical olefine fraction containing alkenes of 8-13 carbon atoms and the product sulphonated with oleum; these sulphonic acids, by themselves or in admixture with naphtha sulphonic acids, are treated with aqueous caustic soda and with aqueous calcium chloride, the water being subsequently removed by distillation. Specification 739,434 also is referred to.ALSO:Basic polyvalent metal salts of organic sulphonic or carboxylic acids are made by adding an aqueous solution of an alkali metal hydroxide and an aqueous solution of an inorganic polyvalent metal salt to a solution of an organic sulphonic or carboxylic acid or a salt thereof (other than an alkali metal salt of an aromatic hydroxycarboxylic acid or mixture thereof with an alkali phenolate, see Specification 759,346) in an anhydrous solvent and removing the water from the reaction mixture by distillation under such conditions that only a part of the solvent is also distilled off.  The water may be removed after each aqueous solution has been added or only after addition of both. Acids specified are petroleum or alkylaromatic sulphonic acids and naphthenic acids.  Benzene, xylene, and gasoline are specified as anhydrous solvents.  The basic solution is preferably added first in excess over that required to form the basic salt having an equivalent proportion of metal hydroxide.  Alkaline earth, aluminium or chromium salts may be prepared by this invention. The basic salts may separate in part from the reaction product, as well as the neutral salts formed and these may be filtered or centrifuged off, followed by extraction of solid or solution, e.g. with a light hydrocarbon oil. The basic salts are additives for lubricating oils and fuel oils.  In examples, an aromatic extract obtained from kerosene with liquid sulphur dioxide was alkylated in presence of aluminium chloride with a technical olefine fraction containing alkenes of 8-13 carbon atoms and the product sulphonated with oleum; these sulphonic acids, by themselves or in admixture with naphtha sulphonic acids, were treated with aqueous caustic soda and with aqueous calcium chloride, the water being subsequently removed by distillation. Specification 739,434 also is referred to.