Structure, Stoichiometry, and Modeling of Calcium Phosphonate Scale-Inhibitor Complexes for Application in Precipitation-Squeeze Processes
- Scott S. Shaw (Heriot-Watt University) | Ken S. Sorbie (Heriot-Watt University)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- March 2014
- Document Type
- Journal Paper
- 139 - 151
- 2014.Society of Petroleum Engineers
- 4.3.4 Scale, 4.1.2 Separation and Treating
- stoichiometry, calcium, phosphonate, scale, inhibitor
- 0 in the last 30 days
- 286 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 5.00|
|SPE Non-Member Price:||USD 35.00|
Phosphonate scale inhibitors (SIs) applied in downhole-squeeze applications may be retained in the near-well formation through adsorption and/or precipitation mechanisms. In this paper, we focus on the properties of precipitated calcium phosphonate complexes formed by nine common phosphonate species. The stoichiometry [calcium ion to phosphorous (Ca2+/P) ratios] in various precipitates is established experimentally, and the effect of solution pH on the molar ratio of Ca2+/P in the precipitate is investigated. All static precipitation tests were carried out in distilled water (DW), with only Ca2+ [as calcium chloride (CaCl2)] and SI present in the system at test temperatures from 20 to 95°C. The molar ratio of Ca2+/P in the solid precipitate was determined by assaying for Ca2+ and P in the supernatant liquid under each test condition by inductively coupled plasma (ICP) spectroscopy (Ca0 and P0 are known, but are also measured experimentally). We show experimentally that the molar ratio of precipitated Ca2+/P (or Ca2+/SI; or n in the SI–Can complex) depends on the SI itself and is a function of pH for all phosphonates tested. It is found that, as pH increases, the molar ratio of Ca2+/P (n in the SI–Can) in the precipitate increases up to a theoretical maximum, depending on the chemical structure of the phosphonate. Our findings corroborate proposed SI-metal complex-ion structures, which were presented previously in Shaw et al. (2012c), as discussed in detail in this paper. In addition, the precipitation behavior of the various compounds is modeled theoretically by developing and solving a set of simplified equilibrium equations. We find that the precipitation behavior can be modeled, but only if a fraction (β) of "non-SI" of the initial phosphonate SI is taken into account. The quantity β can be as high as 0.2 (i.e., approximately 20% non-SI), although there is a degree of variability in this factor from product to product. However, good quantitative agreement is shown comparing the predictions of the equilibrium-solubility model with the experiment. Such models can be used directly in the modeling of field phosphonate precipitation-squeeze treatments.
|File Size||921 KB||Number of Pages||13|
Barnett, B.L. and Uchtman, V.A. 1979. Structural investigations of calcium-binding molecules. 4. Calcium binding to aminocarboxylates. Crystal structures of Ca(CaEDTA).7H2O and Na(CaNTA). Inorg. Chem. 18 (10): 2674–2678. http://dx.doi.org/10.1021/ic50200a007.
Billo, E.J. 2001. Calculation of Binding Constants. In Excel® for Chemists: A Comprehensive Guide, second edition, Chap. 22, 349–372. New York: John Wiley & Sons.
Boak, L.S., Graham, G.M., and Sorbie, K.S. 1999. The Influence of Divalent Cations on the Performance of BaSO4 Scale Inhibitor Species. Presented at the SPE International Symposium on Oilfield Chemistry, Houston, 16–19 February. SPE-50771-MS. http://dx.doi.org/10.2118/50771-MS.
Browning, F.H. and Fogler, H.S. 1995. Effect of Synthesis Parameters on the Properties of Calcium Phosphonate Precipitates. Langmuir 11 (10): 4143–4152. http://dx.doi.org/10.1021/la00010a082.
Demadis, K.D. and Katarachia, S.D. 2004. Metal-Phosphonate Chemistry: Synthesis, Crystal Structure of Calcium-Amino-Tris-(Methylene Phosphonate) and Inhibition of CaCO3 Crystal Growth. Phosphorus, Sulfur, and Silicon and the Related Elements 179: 627–648. http://dx.doi.org/10.1080/10426500490441514.
Duan, W., Oota, H., and Sawada, K. 1999. Stability and structure of ethylenedinitrilopoly(methylphosphonate) complexes of the alkaline-earth metal ions in aqueous solution. J. Chem. Soc., Dalton Trans. (17): 3075–3080. http://dx.doi.org/10.1039/A904461B.
Greenwood, N.N. and Earnshaw, A. 1997. Chemistry of the Elements, second edition. Oxford: Butterworth-Heinemann.
Graham, G.M., Boak, L.S., and Sorbie, K.S. 1997. The Influence of Formation Calcium on the Effectiveness of Generically Different Barium Sulphate Oilfield Scale Inhibitors. Presented at the SPE International Symposium on Oilfield Chemistry, Houston, 18–21 February. SPE-37273-MS. http://dx.doi.org/10.2118/37273-MS.
Graham, G.M., Boak, L.S., and Sorbie, K.S. 2003. The Influence of Formation Calcium and Magnesium on the Effectiveness of Generically Different Barium Sulphate Oilfield Scale Inhibitors. SPE Prod & Fac 18 (1): 28–44. SPE-81825-PA. http://dx.doi.org/10.2118/81825-PA.
Litchinsky, D., Purdie, N., Tomson, M.B., and White, W.D. 1969. Rigorous solution to the problem of interfering dissociation steps in the titration of polybasic acids. Anal. Chem. 41 (13): 1726–1730. http://dx.doi.org/10.1021/ac60282a007.
Martell, A.E. 1971a. Coordination Chemistry Volume 1. New York City, New York: Van Nostrand Reinhold Co.
Martell, A.E. 1971b. Coordination Chemistry Volume 2. New York City, New York: Van Nostrand Reinhold Co.
Ockerbloom, N. and Martell, A.E. 1958. Chelating Tendencies of Aminomethylenephosphonic-N,N-diacetic Acid. J. Am. Chem. Soc. 80 (10): 2351–2354. http://dx.doi.org/10.1021/ja01543a002.
Oddo, J.E. and Tomson, M.B. 1990. The Solubility and Stoichiometry of Calcium-Diethylenetriaminepenta(Methylene Phosphonate) at 70°C in Brine Solutions at 4.7 and 5.0 pH. Applied Geochemistry 5: 527–532.
Poonia, N.S. and Bajaj, A.V. 1979. Coordination chemistry of alkali and alkaline earth cations. Chem. Rev. 79 (5): 389–445. http://dx.doi.org/10.1021/cr60321a002.
Popov, K., Rönkkömäki, H., and Lajunen, L.H.J. 2001. Critical Evaluation of Stability Constants of Phosphonic Acids. Pure Appl. Chem. 73 (10): 1641–1677. http://old.iupac.org/publications/pac/2001/pdf/7310x1641.pdf.
Sánchez-Moreno, M.J., Fernández-Botello, A., Gómez-Coca, R.B. et al. 2004. Metal ion-binding properties of (1H-benzimidazol-2-yl-methyl)phosphonate (Bimp2-) in aqueous solution. Isomeric equilibria, extent of chelation, and a new quantification method for the chelate effect. Inorg. Chem. 43 (4): 1311–1322. http://dx.doi.org/10.1021/ic030175k.
Sawada, K., Araki, T., and Suzuki, T. 1987. Complex formation of amino polyphosphonates. 1. Potentiometric and nuclear magnetic resonance studies of nitrilotris(methylenephosphonato) complexes of the alkaline-earth-metal ions. Inorg. Chem. 26 (8): 1199–1204. http://dx.doi.org/10.1021/ic00255a005.
Sawada, K., Araki, T., Suzuki, T., and Doi, K. 1989. Complex formation of aminopolyphosphonates. 2. Stability and structure of nitrilotris(methylenephosphonato) complexes of the divalent transition metal ions in aqueous solution. Inorg. Chem. 28 (13): 2687–2688. http://dx.doi.org/10.1021/ic00312a036.
Sawada, K., Kuribayashi, M., Suzuki, T., and Miyamoto, H. 1991. Protonation Equilibria of Nitrilotris(methylenephosphonato)-and Ethylenediamine-tetrakis(methylenephosphonato)- Complexes of Scandium, Yttrium, and Lanthanoids. Journal of Solution Chemistry 20 (8): 829–839. http://dx.doi.org/10.1007/2FBF00675114.
Sawada, K., Miyagawa, T., Sakaguchi, T., and Doi, K. 1993a. Structure and thermodynamic properties of aminopoly-phosphonate complexes of the alkaline-earth metal ions. J. Chem. Soc., Dalton Trans. (24): 3777-3784. http://dx.doi.org/10.1039/DT9930003777.
Sawada, K., Kanda, T., Naganuma, Y., and Suzuki, T. 1993b. Formation and protonation of aminopolyphosphonate complexes of alkaline-earth and divalent transition-metal ions in aqueous solution. J. Chem. Soc., Dalton Trans. (17): 2557–2562. http://dx.doi.org/10.1039/DT9930002557.
Sawada, K., Duan, W., Ono, M., and Satoh, K. 2000. Stability and structure of nitrilo(acetate–methylphosphonate) complexes of the alkaline-earth and divalent transition metal ions in aqueous solution. J. Chem. Soc., Dalton Trans. (6): 919–924. http://dx.doi.org/10.1039/A909207B.
Shaw, S.S., Sorbie, K.S., and Boak, L.S. 2012a. The Effects of Barium Sulfate Saturation Ratio, Calcium, and Magnesium on the Inhibition Efficiency—Part I: Phosphonate Scale Inhibitors. SPE Prod & Oper 27 (3): 306−317. SPE-130373-PA. http://dx.doi.org/10.2118/130373-PA.
Shaw, S.S., Sorbie, K.S., and Boak, L.S. 2012b. The Effects of Barium Sulfate Saturation Ratio, Calcium, and Magnesium on the Inhibition Efficiency: Part II Polymeric Scale Inhibitors. SPE Prod & Oper 27 (4): 390−403. SPE-130374-PA. http://dx.doi.org/10.2118/130374-PA.
Shaw, S.S. and Sorbie, K.S. 2012. The Effect of pH on Static Barium Sulphate Inhibition Efficiency and Minimum Inhibitor Concentration (MIC) of Generic Scale Inhibitors. Presented at the SPE International Conference on Oilfield Scale, Aberdeen, Scotland, UK, 30–31 May. SPE-155094-MS. http://dx.doi.org/10.2118/155094-MS.
Shaw, S.S., Welton, T.D., and Sorbie, K.S. 2012c. The Relation Between Barite Inhibition by Phosphonate Scale Inhibitors and the Structures of Phosphonate-Metal Complexes. Presented at the SPE International Conference on Oilfield Scale, Aberdeen, Scotland, UK, 30–31 May. SPE-155114-MS. http://dx.doi.org/10.2118/155114-MS.
Shaw, S.S. 2012. Investigation into the Mechanisms of Formation and Prevention of Barium Sulphate Oilfield Scale. PhD dissertation, Heriot-Watt University, Edinburgh (May 2012).
Shaw, S.S. and Sorbie, K.S. 2013a. Structure, Stoichiometry, and Modelling of Calcium Phosphonate Scale Inhibitor Complexes for Application in Precipitation Squeeze Processes. Presented at the SPE International Symposium on Oilfield Chemistry, Houston, 8−10 April. SPE-164051-MS. http://dx.doi.org/10.2118/164051-MS.
Shaw, S.S. and Sorbie, K.S. 2013b. Scale-Inhibitor Consumption in Long-Term Static Barium Sulfate Inhibition Efficiency Tests. SPE Prod & Oper 28 (4): 376−386. SPE-164052-PA. http://dx.doi.org/10.2118/164052-PA.
Shaw, S.S. and Sorbie, K.S. 2013c. Experimentally Determined Stoichiometry, Chemical Formulae, and Modelling of Calcium Phosphonate Scale Inhibitor Complexes. Presented at the RSC Chemistry in the Oil Industry XIII, Manchester, UK, 4–6 November.
Shaw, S.S. and Sorbie, K.S. 2014a. Structure and Stoichiometry of Mixed Calcium−Magnesium−Phosphonate Scale Inhibitor Complexes for Application in Precipitation Squeeze Processes. Scheduled for presentation at the NACE International CORROSION 2014 Annual Conference and Exposition, San Antonio, Texas, USA, 9–13 March. NACE-2014-3865.
Shaw, S.S. and Sorbie, K.S. 2014b. Synergistic Properties of Phosphonate and Polymeric Scale Inhibitor Blends for Barium Sulphate Scale Inhibition. Scheduled for presentation at the NACE International CORROSION 2014 Annual Conference and Exposition, San Antonio, Texas, USA, 9–13 March. NACE-2014-3867.
Sorbie, K.S., Graham, G.M., and Jordan, M.M. 2000. How scale inhibitors work and how this affects test methodology. Presented at the 4th International Conference and Exhibition on Chemistry in Industry, Manama, Bahrain, 30 October–1 November.
Sorbie, K.S. and Laing, N. 2004. How Scale Inhibitors Work: Mechanisms of Selected Barium Sulphate Scale Inhibitors Across a Wide Temperature Range. Presented at the SPE International Symposium on Oilfield Scale, Aberdeen, Scotland, UK, 26–27 May. SPE-87470-MS. http://dx.doi.org/10.2118/87470-MS.
Stone, A.T., Knight, M.A., and Nowack, B. 2002. Speciation and Chemical Reactions of Phosphonate Chelating Agents in Aqueous Media. In Chemicals in the Environment, Chap. 4. 59–94. American Chemical Society Symposium Series, 806. http://dx.doi.org/10.1021/bk-2002-0806.ch004.
Tomson, M.B., Kan, A.T., and Oddo, J.E. 1994. Acid/Base and Metal Complex Solution Chemistry of the Polyphosphonate DTPMP versus Temperature and Ionic Strength. Langmuir 10 (5): 1442–1449. http://dx.doi.org/10.1021/la00017a021.
Tomson, M.B., Fu, G., Watson, M.A., and Kan, A.T. 2002. Mechanisms of Mineral Scale Inhibition. Presented at the SPE Internation Symposium on Oilfield Scale, Aberdeen, Scotland, UK, 30–31 January. SPE-74656-MS. http://dx.doi.org/10.2118/74656-MS.
Tomson, M.B., Fu, G., Watson, M.A. and Kan, A.T. 2003. Mechanisms of Mineral Scale Inhibition. SPE Prod & Fac 18 (3): 192−199. SPE-84958-PA. http://dx.doi.org/10.2118/84958-PA.
Tomson, M.B., Kan, A.T., Fu, G., and Al-Thubaiti, M. 2004. A Molecular Theory of Mineral Scale Inhibition. Paper NACE-04075 presented at CORROSION 2004, New Orleans, Louisiana, USA, 28 March–1 April.
Uchtman, V.A. 1972. Structural investigations of calcium binding molecules. II. Crystal and molecular structures of calcium dihydrogen ethane-1-hydroxy-1,1-diphosphonate dihydrate, CaC(CH3)(OH)(PO3H)2.2H2O. Implications for polynuclear complex formation. J. Phys. Chem. 76 (9): 1304–1310. http://dx.doi.org/10.1021/j100653a014.
Uchtman, V.A. and Gloss, R.A. 1972. Structural investigations of calcium binding molecules. I. Crystal and molecular structures of ethane-1-hydroxy-1,1-diphosphonic acid monohydrate, C(CH3)(OH)(PO3H2)2.H2O. J. Phys. Chem. 76 (9): 1298–1304. http://dx.doi.org/10.1021/j100653a013.
Uchtman, V.A. and Oertel, R.P. 1973. Structural investigations of calcium binding molecules. III. Calcium-oxydiacetic acid system. Crystal and molecular structures of calcium oxydiacetate hexahydrate and Raman spectroscopic comparison with species in aqueous solution. J. Am. Chem. Soc. 95 (6): 1802–1811. http://dx.doi.org/10.1021/ja00787a019.
Uchtman, V.A. and Jandacek, R.J. 1980. Structural investigations of calcium-binding molecules. 5. Structure analysis of a calcium salt of benzenehexacarboxylic acid (mellitic acid), Ca2C12H2O12.9H2O. Inorg. Chem. 19 (2): 350–355. http://dx.doi.org/10.1021/ic50204a015.
Xiao, J.A., Kan, A.T., and Tomson, M.B. 2001. Acid-Base and Metal Complexation Chemistry of Phosphino-polycarboxylic Acid under High Ionic Strength and High Temperature. Langmuir 17 (15): 4661–4667. http://dx.doi.org/10.1021/la001720m.