GB975360A - High metal-content complex carbonate-alkyl phenate sulphide salts and oil compositions containing the same - Google Patents

Abstract

Complex carbonate-phenate sulphide salts are prepared by: (1) forming a methanol suspension of calcium hydroxide or a methanol solution of an alkaline earth metal hydroxide or hydroxymethylate, the suspension or solution containing at least 200ml of methanol per equivalent of metal; (2) passing CO2 into the suspension or solution at below 30 DEG C. (except in the case of barium hydroxymethylate when the temperature is higher than 30 DEG C. but below the boiling point of methanol), the mol ratio CO2: metal being 0.6-2.0:1; (3) forming a reaction mixture of the composition formed in (2) with a hydrocarbon solution of a compound of formula <FORM:0975360/C1/1> wherein R is a C5-24 alkyl radical, x is an integer 1-4, y is 0 or an integer 1-3, y is an integer 1-5, or an alkali or alkaline earth metal salt of said compound, in a proportion such that 2-4 equivalents of metal are supplied by the said composition per equivalent of OH hydrogen supplied by the phenol sulphide, or 1-3 equivalents of metal are supplied by the said composition per equivalent of OH hydrogen in the precursor of the phenol sulphide salt; (4) removing methanol from the reaction mixture and (5) filtering the reaction mixture to recover a hydrocarbon solution of the desired complex salt. In a modification, the CO2 may be passed into a methanol solution of alkaline earth dimethylate prior to its hydrolysis to hydroxymethylate.ALSO:A mineral lubricating oil contains a minor amount of a high metal content complex carbonate-phenate sulphide prepared under specific conditions (see Division C2). The metal content consists of alkaline earth metals including magnesium and optionally alkali metals. The usual additives may also be present.