US4500356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methylenephosphonic acid derivatives of bis(aminoalkyl)piperazines as cement set retarding agents
Assignee: Schlumberger Technology Corp
•
Filing: 1984-02-24
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Granted: 1985-02-19
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Expires: 2004-02-24
Abstract
Abstract Methylenephosphonic acid derivatives of bis(aminoalkyl)piperazine are employed as cement set retarding additives. The compounds must have at least one of the amine hydrogens phosphonomethylated.
Inventors
- 👤 Druce K. Crump
- 👤 Jaime Simon
- 👤 David A. Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:06
CPC Classifications
C; C08; C08G; C08G12/00; C08G12/02; C08G12/40; C04; C04B; C04B24/00; C04B24/003; C07; C07F; C07F9/00; C07F9/02; C07F9/547; C07F9/645; C07F9/6509; C07F9/650952
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
125 words
In a process for retarding the setting of an aqueous cement slurry which comprises adding to said slurry an organic phosphonate, the improvement which comprises employing a compound which is a phosphonomethylated bis(aminoalkyl)piperazine having the formula ##STR2## wherein n is 2-3 and wherein substituents A, B, X and Y each are independently selected from radicals consisting of hydrogen, hydroxyalkyl (wherein the alkyl group contains 2-6 carbon atoms); methylenephosphonic; methylene-, ethylene- and propylenesulfonic; hydroxymethyl-, hydroxyethyl- and hydroxypropylsulfonic acid radicals; carboxylic acid radicals (having 2-4 carbon atoms) and the alkali, alkaline earth metal, ammonium and amine salts of any of the phosphonic, sulfonic or carboxylic acid derivatives, and wherein at least one of A, B, X and Y is a methylenephosphonic acid radical or a salt thereof.
Claim 2
Dependent Claim
125 words
In a process for retarding the setting of an aqueous cement slurry which comprises adding to said slurry an organic phosphonate, the improvement which comprises employing a compound which is a phosphonomethylated bis(aminoalkyl)piperazine having the formula ##STR2## wherein n is 2-3 and wherein substituents A, B, X and Y each are independently selected from radicals consisting of hydrogen, hydroxyalkyl (wherein the alkyl group contains 2-6 carbon atoms); methylenephosphonic; methylene-, ethylene- and propylenesulfonic; hydroxymethyl-, hydroxyethyl- and hydroxypropylsulfonic acid radicals; carboxylic acid radicals (having 2-4 carbon atoms) and the alkali, alkaline earth metal, ammonium and amine salts of any of the phosphonic, sulfonic or carboxylic acid derivatives, and wherein at least one of A, B, X and Y is a methylenephosphonic acid radical or a salt thereof.
Claim 3
Dependent Claim
27 words
The process of claim 1 wherein the compound is one in which each A, B, X and Y is a methylenephosphonic acid group or a salt thereof.
Claim 4
Dependent Claim
31 words
The process of claim 1 wherein the compound employed is one in which three of A, B, X and Y substituents are methylenephosphonic acid groups and the remaining one is hydrogen.
Claim 5
Dependent Claim
21 words
The process of claim 3 wherein the compound employed contains a hydroxypropylsulfonic acid group in place of the remaining amine hydrogen.
Claim 6
Dependent Claim
18 words
The process of claim 3 wherein the acid groups of the compound employed are in the salt form.
Claim 7
Dependent Claim
18 words
The process of claim 4 wherein the acid groups of the compound employed are in the salt form.
Claim 8
Dependent Claim
21 words
The process of claim 3 wherein the compound employed contains a --CH 2 COOH group in place of the amine hydrogen.
Claim 9
Dependent Claim
19 words
The process of claim 3 wherein the compound employed contains a hydroxypropyl group in place of the amine hydrogen.
Claim 10
Dependent Claim
14 words
The process of claim 7 wherein the acid groups are in the salt form.
Claim 11
Dependent Claim
14 words
The process of claim 8 wherein the acid groups are in the salt form.
Claim 12
Dependent Claim
12 words
The process of claim 5 wherein the salt is that of sodium.
Claim 13
Dependent Claim
12 words
The process of claim 6 wherein the salt is that of sodium.
Claim 14
Dependent Claim
12 words
The process of claim 9 wherein the salt is that of sodium.
Claim 15
Dependent Claim
12 words
The process of claim 10 wherein the salt is that of sodium.
Claim 16
Dependent Claim
19 words
The process of claim 1 wherein the temperature of the cement slurry is at least 180° F. (˜82° C.).
Claim 17
Dependent Claim
15 words
The process of claim 1 wherein the cement slurry is injected into an oil well.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |