Claims
- 1. Method of fracturing a subterranean formation comprising adding to a hydrocarbon liquid to be used as a fracturing fluid (a) about 0.3% to about 1.5% by weight, based on the hydrocarbon liquid, of an organic phosphate of the formula HPO.sub.4 RR' where R is a straight or branch chain alkyl, aryl, alkoxy or alkaryl group having from 6 to about 18 carbon atoms and R' is hydrogen or an aryl, alkaryl, alkoxy or alkyl group having from 1 to about 18 carbon atoms, and (b) a composition comprising (i) ferric iron in an amount sufficient to form a gel with said organic phosphate in said hydrocarbon liquid, and (ii) a polycarboxylic acid or an alkali metal salt thereof, having from 2-12 carbon atoms and up to three amine groups, and fracturing a subterranean formation with said hydrocarbon liquid.
- 2. Method of claim 1 wherein said composition (b) is added in an amount sufficient to provide 0.1 to 2.5 mole(s) of ferric iron for each mole of phosphate ester present in said hydrocarbon.
- 3. Method of claim 1 wherein said polycarboxylic acid or alkali metal salt thereof is present in a weight ratio of about 1:10 to about 10:1 to said ferric iron.
- 4. Method of claim 1 wherein an amine of the formula ##STR9## where R' is --(CH.sub.2).sub.2-6 R.sup.4, R.sup.4 is H or OH, R.sup.2 is --(CH.sub.2).sub.0-6 H or --(CH.sub.2).sub.2-4 OH,
- R.sup.3 is R.sup.2 or ##STR10## and R.sup.5 is R.sup.2 or ##STR11## is also a part of composition (b), in a weight ratio to ferric iron of 1:10 to 10:1.
- 5. Method of claim 1 wherein said polycarboxylic acid or alkali metal salt thereof is ethylene diamine tetraacetic acid or an alkali metal salt thereof.
- 6. Method of claim 1 wherein said polycarboxylic acid or alkali metal salt thereof is nitrilotriacetic acid or an alkali metal salt thereof.
- 7. Method of claim 1 wherein said polycarboxylic acid or an alkali metal salt thereof is tartaric acid.
- 8. Method of claim 1 wherein said polycarboxylic acid or an alkali metal salt thereof is citric acid.
- 9. Method of claim 1 wherein said polycarboxylic acid as of the formula ##STR12##
- 10. A composition for viscosifying a hydrocarbon containing a phosphate ester comprising (a) ferric iron (b) a polycarboxylic acid or alkali metal salt thereof having 2-12 carbon atoms and up to three amine groups in a weight ratio to said ferric iron of about 1:10 to about 10:1, and (c) an amine of the formula ##STR13## where R' is --(CH.sub.2).sub.2-6 R.sup.4, R.sup.4 is H or OH, R.sup.2 is --(CH.sub.2).sub.0-6 H or --(CH.sub.2).sub.2-4 OH,
- R.sup.3 is R.sup.2 or ##STR14## and R.sup.5 is R.sup.2 or ##STR15## in an amount up to about ten times by weight of the ferric iron.
- 11. Composition of claim 10 wherein said polycarboxylic acid or alkali metal salt thereof is ethylene diamine tetraacetic acid or an alkali metal salt thereof.
- 12. Composition of claim 10 wherein said polycarboxylic acid or alkali metal salt thereof is nitrilotriacetic acid of an alkali metal salt thereof.
- 13. Composition of claim 10 wherein said polycarboxylic acid or alkali metal salt thereof is tartaric acid.
- 14. Composition of claim 10 wherein said polycarboxylic acid or alkali metal salt thereof is citric acid.
- 15. A viscous fracturing fluid comprising a hydrocarbon liquid including about 0.3% to 1.5% by weight of an organic phosphate gelling agent, about 0.1 to about 2.5 mole(s) of ferric iron for each mole of phosphate gelling agent, a polycarboxylic acid or alkali metal salt thereof in a weight ratio of 1:10 to 10:1 to the ferric iron, and up to ten times the weight of the ferric iron of an amine of the formula ##STR16## where R' is (CH.sub.2).sub.2-6 R.sup.4, R.sup.4 is H or OH, R.sup.2 is (CH.sub.2).sub.0-6 H or (CH.sub.2).sub.2-4 OH,
- R.sup.3 is R.sup.2 or ##STR17## and R.sup.5 is R.sup.2 or ##STR18##
- 16. Fracturing fluid of claim 15 wherein said polycarboxylic acid is of the formula ##STR19##
- 17. Fracturing fluid of claim 15 wherein said polycarboxylic acid or alkali metal salt thereof is ethylene diamine tetraacetic acid or an alkali metal salt thereof.
- 18. Fracturing fluid of claim 15 wherein said polycarboxylic acid or alkali metal salt thereof is nitrilotriacetic acid.
- 19. Fracturing fluid of claim 15 wherein said polycarboxylic acid or alkali metal salt thereof is tartaric acid.
- 20. Fracturing fluid of claim 15 wherein said polycarboxylic acid or alkali metal salt thereof is citric acid.
- 21. Fracturing fluid of claim 15 wherein said polycarboxylic acid or alkali metal salt thereof is of the formula ##STR20## or an alkali metal salt thereof.
RELATED APPLICATION
This application is a continuation-in-part of (a) our U.S. patent Application Ser. No. 08/592,592 filed Jan. 26, 1996 now U.S. Pat. No. 5,614,010 and (b) our U.S. patent application Ser. No. 08/580,171 filed Dec. 28, 1995, now U.S. Pat. No. 5,571,315, both of which are continuations-in-part of U.S. patent application Ser. No. 08/360,438 filed Dec. 21, 1994, now abandoned, which is a division of application Ser. No. 08/209,266 filed Mar. 14, 1994 now U.S. Pat. No. 5,417,287.
US Referenced Citations (14)
Divisions (1)
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209266 |
Mar 1994 |
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Continuation in Parts (3)
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592592 |
Jan 1996 |
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580171 |
Dec 1995 |
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360438 |
Dec 1994 |
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