Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
156 words
In a method for the recovery of oil from a subterranean oil reservoir penetrated by spaced injection and production systems in which an aqueous fluid is introduced into said reservoir via said injection system to displace oil to said production system, the improvement comprising employing as at least a portion of the fluid introduced into said injection system an aqueous liquid containing a water-soluble anionic surfactant characterized by the formula: ##STR5## wherein is a lipophilic base provided by a C 8 -C 20 aliphatic hydrocarbon group or an aryl group substituted with a C 6 -C 18 aliphatic hydrocarbon group, R 2 is a C 1 -C 4 aliphatic group, n is 2 or 3, x is a number within the range of 1-10, R 3 is a C 2 -C 4 alkane group, R 4 is hydrogen, a hydroxy group or a methyl group, and M is an alkali metal, ammonium, or substituted ammonium ion.
Claim 2
Dependent Claim
156 words
In a method for the recovery of oil from a subterranean oil reservoir penetrated by spaced injection and production systems in which an aqueous fluid is introduced into said reservoir via said injection system to displace oil to said production system, the improvement comprising employing as at least a portion of the fluid introduced into said injection system an aqueous liquid containing a water-soluble anionic surfactant characterized by the formula: ##STR5## wherein is a lipophilic base provided by a C 8 -C 20 aliphatic hydrocarbon group or an aryl group substituted with a C 6 -C 18 aliphatic hydrocarbon group, R 2 is a C 1 -C 4 aliphatic group, n is 2 or 3, x is a number within the range of 1-10, R 3 is a C 2 -C 4 alkane group, R 4 is hydrogen, a hydroxy group or a methyl group, and M is an alkali metal, ammonium, or substituted ammonium ion.
Claim 3
Dependent Claim
48 words
The method of claim 1 wherein R 1 is a C 14 -C 18 aliphatic group or an aryl group substituted with a C 12 -C 18 aliphatic group, R 2 is a methyl group, n is 2, and x is a numbr within the range of 1-4.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein R 3 contains 2 or 3 carbon atoms and R 4 is hydrogen.
Claim 5
Dependent Claim
21 words
The method of claim 2 wherein R 3 contains 2 or 3 carbon atoms and R 4 is a hydroxy group.
Claim 6
Dependent Claim
165 words
In a method for the recovery of oil from a subterranean oil reservoir penetrated by spaced injection and production systems in which an aqueous fluid is introduced into said reservoir via said injection system to displace oil to said production system, the improvement comprising employing as at least a portion of the fluid introduced into said injection system an aqueous liquid containing a water-soluble anionic surfactant characterized by the formula: ##STR6## wherein R a is a lipophilic base provided by a C 10 -C 25 aliphatic hydrocarbon group or an aryl group substituted by a C 8 -C 23 aliphatic hydrocarbon group, n is 2 or 3, x 1 and x 2 are each independently a number within the range of 1-10, R b and R d are each independently a C 2 -C 4 alkane group, R c and R e are each independently a hydrogen, a hydroxy group, or a methyl group, and M is an alkali metal, ammonium, or substituted ammonium ion.
Claim 7
Dependent Claim
165 words
In a method for the recovery of oil from a subterranean oil reservoir penetrated by spaced injection and production systems in which an aqueous fluid is introduced into said reservoir via said injection system to displace oil to said production system, the improvement comprising employing as at least a portion of the fluid introduced into said injection system an aqueous liquid containing a water-soluble anionic surfactant characterized by the formula: ##STR6## wherein R a is a lipophilic base provided by a C 10 -C 25 aliphatic hydrocarbon group or an aryl group substituted by a C 8 -C 23 aliphatic hydrocarbon group, n is 2 or 3, x 1 and x 2 are each independently a number within the range of 1-10, R b and R d are each independently a C 2 -C 4 alkane group, R c and R e are each independently a hydrogen, a hydroxy group, or a methyl group, and M is an alkali metal, ammonium, or substituted ammonium ion.
Claim 8
Dependent Claim
49 words
The method of claim 5 wherein R a is a C 16 -C 20 aliphatic group or an aryl group substituted with a C 14 -C 18 aliphatic group, n is 2, and x 1 and x 2 are each independently a number of within the range of 1-4.
Claim 9
Dependent Claim
27 words
The method of claim 6 wherein R b and R d each independently contains 2 or 3 carbon atoms and R c and R e are hydrogen.
Claim 10
Dependent Claim
28 words
The method of claim 6 wherein R b and R d each independently contains 2 or 3 carbon atoms and R c and R e are hydroxy groups.