Process for the preparation of superbase additives and compositions containing the said additives

摘要

Process for the preparation of very fluid and stable superbase additives of high basicity by bringing an alkali or alkaline-earth metal derivative and at least one surfactant into contact with carbon dioxide in a diluent oil and a hydrocarbon solvent, in the presence of an oxygenated promoter and of a nitrogenous promoter, characterised in that the temperature at the beginning of the carbonation is allowed to change up to a value of between 25 and 60 DEG C and the temperature is then maintained at this value during the optimum carbonisation period, determined by measuring the alkalinity value. The additives according to the invention are employed in lubricating oils and fuel oils.