Superalkalinized isomerized linear alkylaryl sulfonates of alkaline earth metals, useful as detergent/dispersant additives for lubricating oils, and processes for their preparation and intermediate alkylaryl hydrocarbon

A process for the preparation of an alkylaryl hydrocarbon comprising an aryl substituent other than phenyl on a linear alkyl chain containing between 14 and 40 carbon atoms, wherein the molar proportion of aryl substituent on positions 1 and 2 of the linear alkyl chain is comprised between 0 and 13%, said process comprising the alkylation, by the Friedel-Crafts reaction, of an aryl hydrocarbon other than benzene by a linear mono-olefin containing between 14 and 40 carbon atoms, and having a molar proportion of alpha olefin of at least 80% wherein the alkylation takes place in a first step in which the molar ratio between the aryl hydrocarbon and the linear mono-alpha olefin is a maximum of 1.5, and in a second step in which said ratio is a minimum of 2.

A superalkalinized alkylaryl sulfonate of alkaline earth metal, wherein the aryl radical is other than phenyl, wherein the alkyl chain is a linear chain that contains between 14 and 40 carbon atoms, and wherein said aryl-sulfonate radical of alkaline earth metal is fixed, in a molar proportion comprised between 0 and 13% in positions 1 or 2 of the linear alkyl chain.