| abstract |
A stable dispersion of a metal compound in a non-volatile carrier is prepared by:-(a) mixing an alkoxide and/or alcohol-soluble carbonate of the alkoxide of a metal from Group Ib, IIa, IIb, IIIa, IIIb, IVa, IVb, Va, Vb, VIb, VIIb, and VIII of the Periodic Table according to Deming, an oil-soluble dispersing agent, a nonvolatile carrier, and water; (b) hydrolysing the metal alkoxide to an oil-insoluble metal compound and (c) removing the volatile materials from the mixture; the said metal alkoxide having been prepared by reacting an alkali metal or alkali metal hydroxide with an alcohol to form an alkali metal alkoxide, and then reacting a salt of the said metal with the alkali metal alkoxide in an alcoholic solution to form a metal alkoxide, the resulting alkali metal salt being less soluble in the alcoholic solution than the metal salt. The alcoholic solution of the metal salt may be stabilized by carbonating the solution by passing in carbon dioxide. The process is particularly suitable for preparing dispersions of compounds of chromium, molybdenum, manganese, iron, cobalt, nickel, copper, zinc, cadmium, tin, lead, vanadium, zirconium, silver, mercury, arsenic, antimony and bismuth. Suitable alcohols for use in the process are alkanols having 1-6 carbon atoms, monoethers of ethylene glycol containing not more than 8 carbon atoms, and monoethers of diethylene glycol containing not more than 8 carbon atoms. The non-volatile carriers used in the dispersion include mineral lubricating oils, vegetable oils and synthetic oils such as propylene polymers, polyoxyalkylenes, and esters of dicarboxylic acids or phosphorus acids, the preferred ones being mineral or synthetic lubricating oils. The non-volatile carriers may be diluted with a solvent, e.g. petroleum naphtha or hydrocarbons, to reduce the viscosity. Suitable oil-soluble dispersing agents include oil-soluble sulphonic acids, carboxylic acids, phosphorus sulphide-treated olefines, phenolic organic compounds and metal salts thereof. The preferred dispersing agents are sulphonates, e.g. alkyl and aryl sulphonates, mahogany soaps and wax sulphonates the wax being obtained from crude petroleum oil, and carboxylic acids, e.g. naphthenic acids such as cetyl cyclohexane carboxylic acids, dioctyl cyclopentane carboxylic acids, dilauryl decahydronaphthalene and stearyl-octahydroindene carboxylic acids and oil-soluble salts thereof, and fatty acids such as 2-ethyl hexanoic acid, pelargonic acid, oleic acid linoleic acid and ricinoleic acid. Specification 906,208 is referred to.ALSO:Alkoxides of metals of Group Ib, IIa, IIb, IIIa, IIIb, IVa, IVb, Va, Vb, VIb, VIIb and VIII of the Periodic Table (according to Deming) are prepared by reacting an alkali metal or alkali metal hydroxide with an alcohol to form an alkali metal alkoxide and then reacting a salt of one of the above specified metals with the alkali metal alkoxide in an alcoholic solution to form the metal alkoxide, the resulting alkali metal salt being less soluble in the alcoholic solution than the starting metal salt. Preferably the alcohol is an aliphatic monohydric alcohol having 1-6 carbon atoms, a monoether of ethylene glycol having not more than 8 carbon atoms or a monoether of diethylene glycol having not more than 8 carbon atoms. The metal salts used as starting materials may be, for example, a halide, nitrate, sulphate, acetate, ammonium phosphate, bromate, carbonate, citrate, cyamide, dithionate, formate, iodate, nitrite, oxalate, phosphate, silicate, sulphate, sulphite, tartrate, aluminate, antimonate, arsenate, bismuthate, borate, chromate, manganate, molybdate, selenate, tungstate, uranate or vanadate and the metal salts are preferably those of aluminium, silver, arsenic, barium, bismuth, calcium, cadmium, cobalt, chromium, copper, iron, mercury, magnesium, manganese, molybdenum, nickel, lead, antimony, strontium, tin, vanadium, zinc and zirconium. In some cases it may be necessary to carbonate the metal alkoxide in order to stabilize the alcoholic solution. The carbonating is effected by passing carbon dioxide through the system and the product is a metal alkoxide carbonate complex. Specification 906,208 is referred to.ALSO:A stable dispersion for use as an additive for fuels or lubricating oils is prepared by: (a) mixing an alkoxide and/or alcohol-soluble carbonate of the alkoxide of a metal from Groups Ib, IIa, IIb, IIIa, IIIb, IVa, IVb, Va, Vb, VIb, VIIb and VIII of the Periodic Table according to Denning, an oil-soluble dispersing agent, a non-volatile carrier and water; (b) hydrolysing the metal alkoxide to an oil-insoluble metal compound, and (c) removing the volatile materials from the mixture. The preferred metals are chromium, molybdenum, manganese, iron, cobalt, nickel, copper, zinc, cadmium, tin, lead, vanadium, zirconium, silver, mercury, arsenic, antimony and bismuth. Suitable alcohol constituents of the alkoxide are C1-C6 alkanols and monoethers of ethylene glycol and diethylene glycol having not more than 8 carbon atoms. The non-volatile carriers used in the dispersion include mineral lubricating oils, vegetable oils and synthetic oils. The non-volatile carriers may be diluted with a solvent, for example petroleum naphtha or hydrocarbons, to reduce the viscosity. Suitable oil-soluble dispersing agents include oil-soluble sulphonic acids, carboxylic acids, phosphorus sulphide-treated olefines, phenolic organic compounds and metal salts thereof. The preferred dispersing agents are sulphonates, e.g. alkyl and aryl sulphonates, mahogany soaps and wax sulphonates, the wax being obtained from crude petroleum oils, and naphthenic acids. The dispersions may be added to internal-combustion engine lubricating compositions and may be used as corrosion inhibitors in vanadium-containing fuels and as additives to fuels in general. Specification 906,208 is referred to. |