New colloidal products, their preparation and their uses

摘要

New colloidal super-basic compounds comprise a micellar core of an alkali or alkaline earth carbonate surrounded by a crown consisting of a surfactant chosen from dihydrocarbyl- dithiophosphoryl-alkane-sulphonic acids of general formula: (RO)2P(S)(S-(CH2)n-SO3H (I) where R = 1 - 30C monovalent hydrocarbyl (aliphatic, cycloaliphatic or aromatic), and n = 3 - 8, and their alkali or alkaline earth salts. The colloidal product is derived from the carbonation of at least one alkali or alkaline earth hydroxide carried out in an oily medium in the presence of the dihydrocarbyl-dithiophosphoryl-alkane-sulphonic acid. It is prepared by the following steps: (a) introduction of at least one acid or acid salt of a dihydrocarbyl- dithiophosphoryl- alkane-sulphonic acid in an oily hydrocarbon medium and at least one alkali or alkaline earth oxide or hydroxide in the presence of an aliphatic, cycloaliphatic or aromatic solvent, and (as promoter) an oxygenated organic liquid; (b) carbonation by introduction of CO2 into the stirred mixture; (c) after completion of the reaction, unreacted particles of oxide or hydroxide are filtered off, and the oxygenated organic compound decanted; and (d) the hydrocarbon solvent is evaporated off to obtain the colloidal product as a clear suspension in the original oily hydrocarbon. In step (a) the oily medium may be a mineral or synthetic oil; the concentration of the dihydrocarbyl-diphosphoryl- alkane-sulphonic acid or salt is from 5 - 100% wt. relative to the oily medium; the oxide or hydroxide is present in a proportion of 20 - 200% wt. relative to the acid or salt; the proportion of solvent is such that the concentration of reactants is 2 - 70% wt.; and the oxygenated organic compound is present as 5 - 40% vol. relative to the solvent. In step (b), the carbonation is effected at ambient up to 45 degrees C.