Marine diesel engine lubricating oil compositions

摘要

Disclosed herein are marine diesel engine lubricating oil compositions which comprises (a) a major amount of an oil of lubricating viscosity, and (b) about 3 wt. % to about 40 wt. %, based on the total weight of the marine diesel engine lubricating oil composition, of a sulfurized, alkaline earth metal alkylphenate detergent which is substantially free of polyol promoter oxidation products.

主权项

1. A marine diesel engine lubricating oil composition which comprises (a) a major amount of an oil of lubricating viscosity, and (b) about 3 wt. % to 14.19 wt. %, based on the total weight of the marine diesel engine lubricating oil composition, of a sulfurized, alkaline earth metal alkylphenate detergent which is substantially free of polyol promoter oxidation products, the sulfurized, alkaline earth metal alkylphenate detergent being prepared by a process comprising (i) contacting an alkylphenol having at least one alkyl substituent from 6 to 36 carbon atoms with sulfur, in the presence of a promoter acid selected from the group of alkanoic acids having 1 through 3 carbon atoms, mixtures of the alkanoic acids, alkaline earth metal salts of the alkanoic acids and mixtures thereof, and at least a stoichiometric amount of a calcium base sufficient to neutralize the alkylphenol and the promoter at a temperature of from about 130° C. to about 250° C. under reactive conditions in the absence of at polyol promoter or an alkanol having 1 to 5 carbon atoms for a sufficient period of time to react essentially all of the sulfur thereby yielding a calcium sulfurized alkylphenate essentially free of elemental sulfur; and (ii) contacting the reaction product of step (i) with carbon dioxide and additional calcium base, if required, to provide the desired TBN, in the presence of an alkylene glycol having 2 to 6 carbon atoms under reactive conditions at a temperature of from about 150° C. to about 260° C., wherein the marine diesel engine lubricating oil composition has a total base number (TBN) of from about 30 to about 70.