Reaction of citric acid with calcite

AlKhaldi, Mohammed; Nasr‐El‐Din, Hisham A.; Mehta, S.; Al-Aamri, Ali

doi:10.1016/j.ces.2007.06.021

Cited by 59 publications

(37 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In solution with a pH of 6, the citrate ions occur mostly as the H 2 Cit 2-and HCit 3-species, the equilibrium being displaced largely towards the former ones [18] [19].…”

Section: Resultsmentioning

confidence: 99%

Thermodynamics of citrate complexation with Mn2+, Co2+, Ni2+ and Zn2+ ions

Wyrzykowski

Chmurzyński

2009

J Therm Anal Calorim

View full text Add to dashboard Cite

show abstract

“…In solution with a pH of 6, the citrate ions occur mostly as the H 2 Cit 2-and HCit 3-species, the equilibrium being displaced largely towards the former ones [18] [19].…”

Section: Resultsmentioning

confidence: 99%

Thermodynamics of citrate complexation with Mn2+, Co2+, Ni2+ and Zn2+ ions

Wyrzykowski

Chmurzyński

2009

J Therm Anal Calorim

View full text Add to dashboard Cite

show abstract

“…As stated earlier, calcium citrate precipitated during the reaction of citric acid with calcite even when low concentrations of citric acid were used. Therefore, it was thought that the calcium citrate precipitation covered the surface of the calcite disk and then it stopped the citric-calcite reaction as reported by Alkhaldi et al (14) when the citric-calcite reaction was carried for two hours. .…”

Section: Calcite Dissolution In Citric Acid Solutionsmentioning

confidence: 85%

“…(13) H2CO3 + H2O  H3O + + HCO3 -……………………………………. (14) HCO3 -+ H2O  H3O + + CO3 2-……………………………………... (15) According to Buijse et al (24) , during the reaction of weak acids with calcite, the final equilibrium pH value will be nearly 4.0 provided that the generated CO 2 stays in solution by applying high pressure > 1000, psi. Based on this, it was concluded that the pH value at surface of the reacted calcite disks is nearly in the range of 4-5, while it remained at 2.3 in the bulk solution.…”

Section: Calcium Citrate Precipitationmentioning

confidence: 97%

See 1 more Smart Citation

Application of Citric Acid in Acid Stimulation Treatments

AlKhaldi¹,

Nasr‐El‐Din²,

Sarma³

2009

Canadian International Petroleum Conference

Self Cite

View full text Add to dashboard Cite

Mass transfer process during the reaction of citric acid with calcite was investigated using the rotating disk apparatus. The effects of disk rotational speed, initial citric acid concentration, and temperature on the effective diffusion coefficient of citric acid were examined.Using various citric acid concentrations (1, 2, 5, 7.5 wt%), the diffusion coefficient of citric acid was calculated at 25, 40, 50°C. The effective diffusion coefficient of citric acid was found to be a function of the interplay between the calcium citrate precipitation and the presence of the counter calcium ions. At high initial acid concentration, (5, 7.5 wt%), the effects of calcium citrate precipitation and counter calcium ions were significant and the calculated citric acid diffusion coefficients were not comparable with its measured effective diffusion coefficients using the rotating disk. However, the effects of both the calcium citrate precipitation and the counter calcium ions on the citric acid diffusivity were minimal at low initial citric acid concentrations.The effect of temperature on the diffusion coefficient of citric acid at a constant citric acid concentration was found to follow Arrhenius law, and the activation energy is equal to 37.9 kJ/mol.

show abstract

“…This instrument has been used extensively to investigate the reaction of HCl, organic acids, and chelating agents with carbonate rocks (Hansford and Litt 1968;Lund et al 1975;de Rozieres et al 1994;Fredd and Fogler 1998a, 1998b, 1998cFredd 1998;Conway et al 1999;Gautelier et al 1999;Gdanski and Van Domelen 1999;Frenier and Hill 2002;Taylor et al 2004aTaylor et al , 2004bTaylor et al , 2006Alkattan et al 1998Alkattan et al , 2002Al-Mohammad et al 2006;Al-Khaldi et al 2007;Nasr-El-Din et al 2008b). It has also been used to study mass and heat transfer in non-Newtonian fluids (Hansford and Litt 1968;de Rozieres et al 1994;Al-Mohammad et al 2006;Nasr-El-Din et al 2008b).…”

Section: Introductionmentioning

confidence: 99%

Quantitative Analysis of Reaction-Rate Retardation in Surfactant-Based Acids

Nasr‐El‐Din

Al-Mohammed

Al-Aamri

et al. 2009

SPE Production &Amp; Operations

View full text Add to dashboard Cite

Fracture acidizing has been a dominant practice in the industry to enhance well productivity in low-permeability carbonate reservoirs. Many acid systems have been developed to improve this stimulation process. The most desirable characteristics for an acid system to be suitable for fracture acidizing are leakoff control and retarded reaction rate. These characteristics are required for deep acid penetration, so that when the fracture closes, long flow channels are etched on the fracture surfaces. Leakoff control can be achieved by pumping a pad containing a viscosifying agent or solid bridging agents to plug wormholes generated by acid dissolution. Reaction retardation is attempted usually by lowering the effective diffusivity of the hydrogen ion.It is well known that during an acid-fracturing operation, the overall reaction rate of hydrochloric acid (HCl) with limestone is mass-transfer-limited. Designing the treatment requires knowing the effective diffusivity of the hydrogen ion in the acid system, which, to the best of the authors' knowledge, has not been determined before. Because of their combined leakoff-control and retardation capabilities, surfactant-based acids have been used in acid-fracturing treatments. Because more carbonate reservoirs are treated by use of this acid system, it is important to obtain the effective diffusivity of H + .The rotating-disk device has been used to investigate the reaction kinetics between a reactive solution and carbonate rocks because the thickness of the boundary layer is uniform throughout the disk surface. This paper discusses the reaction-rate data generated recently for surfactant-based acid by use of a rotating-disk apparatus and presents the methodology used to determine the effective diffusivity from the measurements.The results obtained indicated that the viscoelastic surfactant examined (carboxybetaine-type) reduced the dissolution rate of calcite with HCl acid. The surfactant reduced the diffusion coefficient for H + . The effect of temperature on the diffusion coefficient did not follow the Arrhenius law.

show abstract

Reaction of citric acid with calcite

Cited by 59 publications

References 27 publications

Thermodynamics of citrate complexation with Mn2+, Co2+, Ni2+ and Zn2+ ions

Thermodynamics of citrate complexation with Mn2+, Co2+, Ni2+ and Zn2+ ions

Application of Citric Acid in Acid Stimulation Treatments

Quantitative Analysis of Reaction-Rate Retardation in Surfactant-Based Acids

Contact Info

Product

Resources

About