Patent ID: 8580716

Claim:
A stable, free flowing overbased magnesium oxide dispersion in a high boiling hydrocarbon carrier with a magnesium content of 25-35% by weight based on the total weight of the dispersion, prepared by heating at reflux a mixture comprising 2-10% of an-alkylbenzene sulfonic acid dispersant having a MW of 300 or higher, 10-40% of MgO, 10%-20% water 1-10% of the C 1-5 carboxylic acid, 10-70% of a hydrocarbon carrier having a boiling point of 280° C. or higher selected from mineral oils, alkylated benzenes, oliqomers or polymers of alpha olefins, polycyclic aromatics, alkylated derivatives of polycyclic aromatics and waxes, 5-60% of an alkylated aromatic organic solvent with a boiling point ranging from about 80° C. to about 210° C. for 0.25 to 5 hours, followed by heating to an elevated temperature of 280-360° C. until all water is removed wherein no acidic gas is passed through the mixture of MgO, dispersant, C 1-5 carboxylic acid , water, hydrocarbon carrier having a boiling point of 280° C. or higher and an alkylated aromatic organic solvent with a boiling point ranging from about 80° C. to about 210° C.