The present disclosure provides a method of treating a hydrocarbon-containing reservoir. The method involves introducing into the reservoir a surfactant composition. The surfactant composition includes an alpha olefin sulfonate or an isomerized olefin sulfonate. The alpha olefin sulfonate or the isomerized olefin sulfonate is synthesized by i) oligomerizing a monomer comprising a C.sub.3 to C.sub.6 mono-olefin to form an oligomerization product and ii) sulfonating the oligomerization product.

The present disclosure provides a method of treating a hydrocarbon-containing reservoir. The method involves introducing into the reservoir a surfactant composition. The surfactant composition includes an alpha olefin sulfonate or an isomerized olefin sulfonate. The alpha olefin sulfonate or the isomerized olefin sulfonate is synthesized by i) oligomerizing a monomer comprising a C.sub.3 to C.sub.6 mono-olefin to form an oligomerization product and ii) sulfonating the oligomerization product.

The present invention provides a hydraulic fluid comprising: (a) 40 to 150 ppm by weight in terms of nitrogen content of a corrosion inhibiting agent which is one or more compounds of formula (I):

##STR00001## and/or tribologically acceptable salts thereof, wherein in formula (I): each R.sup.1 is independently a hydrocarbyl group comprising 1 to 10 carbon atoms, x is 0 to 4, and R.sup.2 is hydrogen or a hydrocarbyl group containing 1 to 10 carbon atoms; (b) 1500 to 4000 ppm by weight of an ashless nitrogen-containing dispersant; and (c) a major amount of a base oil.

The present invention provides a hydraulic fluid comprising: (a) 40 to 150 ppm by weight in terms of nitrogen content of a corrosion inhibiting agent which is one or more compounds of formula (I):

##STR00001## and/or tribologically acceptable salts thereof, wherein in formula (I): each R.sup.1 is independently a hydrocarbyl group comprising 1 to 10 carbon atoms, x is 0 to 4, and R.sup.2 is hydrogen or a hydrocarbyl group containing 1 to 10 carbon atoms; (b) 1500 to 4000 ppm by weight of an ashless nitrogen-containing dispersant; and (c) a major amount of a base oil.

Use of a liquid fuel composition in an internal combustion engine, the internal combustion engine containing a lubricating composition for lubricating said internal combustion engine, wherein the liquid fuel composition comprises at least one nitrogen-containing detergent additive, for the purpose of reducing engine wear caused by the presence of soot in the lubricating composition.

Use of a liquid fuel composition in an internal combustion engine, the internal combustion engine containing a lubricating composition for lubricating said internal combustion engine, wherein the liquid fuel composition comprises at least one nitrogen-containing detergent additive, for the purpose of reducing engine wear caused by the presence of soot in the lubricating composition.

The instant disclosure relates to a lubricant composition having an oil of lubricating viscosity, a polymeric surfactant compound that is an acylated polymer having a number average molecular weight of about 500 to about 50,000 where the polymer comprises a branched olefin having from 8 to 30 carbon atoms. The acylated polymer can further be reacted with an amine or alcohol to form an amide, imide, ester or combinations thereof. The present disclosure further relates to lubricant compositions that exhibit good dispersancy and viscometric performance.

The instant disclosure relates to a lubricant composition having an oil of lubricating viscosity, a polymeric surfactant compound that is an acylated polymer having a number average molecular weight of about 500 to about 50,000 where the polymer comprises a branched olefin having from 8 to 30 carbon atoms. The acylated polymer can further be reacted with an amine or alcohol to form an amide, imide, ester or combinations thereof. The present disclosure further relates to lubricant compositions that exhibit good dispersancy and viscometric performance.

The present disclosure describes lubricant compositions effective to minimize average engine sludge through selection of lubricant additives that control the total nitrogen as well as the origin of the nitrogen in the lubricant composition. In aspects, the lubricant compositions herein include at least a base oil of lubricating viscosity, a dispersant system, and at least one antioxidant.

The present disclosure describes lubricant compositions effective to minimize average engine sludge through selection of lubricant additives that control the total nitrogen as well as the origin of the nitrogen in the lubricant composition. In aspects, the lubricant compositions herein include at least a base oil of lubricating viscosity, a dispersant system, and at least one antioxidant.