Patent ID: 7846879

Claim:
An acidic subterranean treatment fluid comprising an acidic fluid and an esterquat wherein the esterquat comprises a reverse esterquat having the general formula: {R (4-m) N + —[(CH 2 ) n —C(O)—O} p —R′] m pX − , wherein R represents a linear or branched chain saturated or unsaturated aliphatic hydrocarbon, aryl, arylalkyl, alkyl amide, hydroxy alkyl, or a mixture thereof, wherein (when there is more than one R group) they may be the same as one another or each may be different from one another; m is an integer in the range from 1 to 3; p is an integer of at least 1; R′ represents a linear or branched chain saturated or unsaturated aliphatic hydrocarbon, aryl, arylalkyl, alkyl amide, or a mixture thereof; n is an integer in the range from 1 to 6; and, X − represents an anionic counter ion, examples of which include, but are not limited to, a halide, sulfate, methosulfate, or methophosphate, and wherein the subterranean treatment fluid has a pH of less than about 4 and further comprises crude oil.