Solubility and Stability of Nesquehonite (MgCO3·3H2O) in NaCl, KCl, MgCl2, and NH4Cl Solutions

Dong, Mei; Cheng, Wenli; Li, Zhibao; Demopoulos, George P.

doi:10.1021/je800438p

Cited by 40 publications

(31 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…26 Though the most commonly grown mineral in aqueous solution at ambient temperature is nesquehonite, it cannot be stable for a long time and will gradually transform to hydromagnesite in nature. 27,28 In this work, therefore, hydromagnesite, the most stable Mg-carbonate except for magnesite, was the focus due to its thermodynamic stability.…”

Section: Theoretical Methodologymentioning

confidence: 99%

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl₂–CO₂–NH₃–H₂O System: Its Potential in CO₂ Sequestration

Wang

2012

Ind. Eng. Chem. Res.

Self Cite

View full text Add to dashboard Cite

The reactive crystallization kinetics of hydromagnesite in the MgCl 2 −CO 2 −NH 3 −H 2 O system, which plays an important role in a new approach to sequester CO 2 with saline sea/lake brines, was systematically investigated by the MSMPR (mixed-suspension-mixed-product removal) crystallization method. The temperature effect on the crystallization of magnesium carbonate hydrates in the system was first investigated batchwise. The optimum temperature of 353.2 K for precipitation of the regular spherical hydromagnesite with good filterability was selected for kinetic study. The supersaturation of hydromagnesite was experimentally tested, and the activity coefficients of aqueous species were strictly calculated by the Pitzer model embedded in the Aspen Plus platform. The nucleation and growth rate and agglomeration kernel were determined by moments analysis based on the PSD (particle size distribution) of crystals in volume coordinates. The corresponding kinetic parameters in three empirical equations were then estimated by linear regression. The resulting volume growth rate order of 2.30 means that surface integration is dominant in the volume growth of hydromagnesite. A simplified process for the new sequestration approach was finally constructed. The value of hydromagnesite as carbonated product was assessed considering the scale-up and costs of such a process. INTRODUCTIONThe rising level of CO 2 in the atmosphere, mainly resulting from the combustion of fossil fuels, and its deleterious impact on the climate continues to raise concerns. Since alternative energy sources are not likely to replace fossil fuels soon, and since the atmospheric concentration of CO 2 is expected to triple by the end of 21st century with the continued growth of emerging densely populated developing countries, it is necessary to develop effective methods of sequestering CO 2 . 1−3 Numerous approaches to CO 2 sequestration, including ocean, terrestrial, geological, chemical, and biological options, are currently being studied, and some commercial scale processes have been demonstrated. 1,3−12 However, the implementation of these methods is limited because of either their extensive energy cost or unsteady behavior of CO 2 . 10 Mineral sequestration via reaction of CO 2 with Mg−Ca silicate rocks in aqueous solutions 11,12 offers an attractive option for the permanent and safe storage of CO 2 in a solid form because the resulting neoformations are thermodynamically stable at ambient temperature. 13 This method, first proposed by Seifritz, 14 requires cations, i.e. Mg and Ca in silicates as olivine and serpentine-group minerals, to neutralize CO 2 through formation of carbonates. Unfortunately, the industrial extraction of Ca and Mg from silicate minerals requires expensiveprocessing, which contributes to the problem rather than to the solution. 15 Furthermore, this option is not at all practical in many countries owing to the paucity of exposed basic and ultrabasic rocks. 3 An attractive alternative involves the interaction of ions in aqueo...

show abstract

Section: Theoretical Methodologymentioning

confidence: 99%

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl₂–CO₂–NH₃–H₂O System: Its Potential in CO₂ Sequestration

Wang

2012

Ind. Eng. Chem. Res.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Only three data sets 119,121,145 are available for the solubility of nesquehonite in the system MgCO 3 Á3H 2 O þ H 2 O, two of which date back to the 19 th century. They are summarized in Table 28.…”

Section: Nesquehonitementioning

confidence: 99%

“…Only two references 145,146 provide data for these systems, both from the same research group. As the MgCO 3 Á3H 2 O þ H 2 O data of this group were accepted, there is reason to believe that the MgCO 3 Á3H 2 O þ H 2 O þ salt data are reliable.…”

Section: Nesquehonitementioning

confidence: 99%

See 1 more Smart Citation

IUPAC-NIST Solubility Data Series. 95. Alkaline Earth Carbonates in Aqueous Systems. Part 1. Introduction, Be and Mg

Visscher

Vanderdeelen

Königsberger

et al. 2012

Journal of Physical and Chemical Reference Data

View full text Add to dashboard Cite

The alkaline earth carbonates are an important class of minerals. This volume compiles and critically evaluates solubility data of the alkaline earth carbonates in water and in simple aqueous electrolyte solutions. Part 1, the present paper, outlines the procedure adopted in this volume in detail, and presents the beryllium and magnesium carbonates. For the minerals magnesite (MgCO 3 ), nesquehonite (MgCO 3 Á3H 2 O), and lansfordite (MgCO 3 Á5H 2 O), a critical evaluation is presented based on curve fits to empirical and=or thermodynamic models. Useful side products of the compilation and evaluation of the data outlined in the introduction are new relationships for the Henry constant of CO 2 with Sechenov parameters, and for various equilibria in the aqueous phase including the dissociation constants of CO 2 (aq) and the stability constant of the ion pair MCO 0 3 ðaqÞ (M ¼ alkaline earth metal). Thermodynamic data of the alkaline earth carbonates consistent with two thermodynamic model variants are proposed. The model variant that describes the Mg 2þ ÀHCO À 3 ion interaction with Pitzer parameters was more consistent with the solubility data and with other thermodynamic data than the model variant that described the interaction with a stability constant.

show abstract

“…No higher temperatures were tried as it is known that MgCO 3 ·3H 2 O was unstable and will easily change to other phases above 50 °C [21]. In this work, 0.5 M Na 2 CO 3 solution (300 ml) was added to 0.5 M MgCl 2 solution (300 ml), 2 h addition and 2 h equilibration after addition.…”

Section: Effect Of Reaction Temperaturementioning

confidence: 99%

Precipitation of nesquehonite from homogeneous supersaturated solutions

Cheng

2009

Cryst. Res. Technol.

Self Cite

View full text Add to dashboard Cite

The homogeneous (unseeded) precipitation of nesquehonite (MgCO 3 ·3H 2 O) was studied over the temperature range of 10-40 °C. Precipitation was triggered by the supersaturation created by mixing MgCl 2 solution (0.5-1.5 M) with Na 2 CO 3 solution in the same concentration range. The Meissner's method was adopted in the calculation of supersaturations during the MgCl 2 -Na 2 CO 3 reaction to monitor the precipitation. Solids were identified using X-ray diffraction (XRD) analysis and scanning electron microscope (SEM) images. In the temperature range of 10-40 °C, MgCO 3 ·3H 2 O with needle-like or gel-like morphology was precipitated. It was seen that the length, width and surface smoothness of the particles changed with reaction temperature and supersaturation. The supersaturation (S) was in the range of 1.09-58.68 during titration of Na 2 CO 3 solution. The dimension of the crystals increased with longer addition time (or lower initial concentration of reactant) at the same temperature. Slower addition via titration of 2 h followed by 2 h of equilibration at 40 °C proved successful in producing well developed needle-like MgCO 3 ·3H 2 O crystals of 30-50 µm long and 3-6 µm wide. MgCO 3 ·3H 2 O obtained were calcined to produce highly pure magnesium oxide (MgO) at 800 °C. The morphology of MgO was similar to that of their corresponding precursors.

show abstract

Solubility and Stability of Nesquehonite (MgCO₃·3H₂O) in NaCl, KCl, MgCl₂, and NH₄Cl Solutions

Cited by 40 publications

References 12 publications

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl₂–CO₂–NH₃–H₂O System: Its Potential in CO₂ Sequestration

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl₂–CO₂–NH₃–H₂O System: Its Potential in CO₂ Sequestration

IUPAC-NIST Solubility Data Series. 95. Alkaline Earth Carbonates in Aqueous Systems. Part 1. Introduction, Be and Mg

Precipitation of nesquehonite from homogeneous supersaturated solutions

Contact Info

Product

Resources

About

Solubility and Stability of Nesquehonite (MgCO3·3H2O) in NaCl, KCl, MgCl2, and NH4Cl Solutions

Cited by 40 publications

References 12 publications

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl2–CO2–NH3–H2O System: Its Potential in CO2 Sequestration

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl2–CO2–NH3–H2O System: Its Potential in CO2 Sequestration

IUPAC-NIST Solubility Data Series. 95. Alkaline Earth Carbonates in Aqueous Systems. Part 1. Introduction, Be and Mg

Precipitation of nesquehonite from homogeneous supersaturated solutions

Contact Info

Product

Resources

About

Solubility and Stability of Nesquehonite (MgCO₃·3H₂O) in NaCl, KCl, MgCl₂, and NH₄Cl Solutions

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl₂–CO₂–NH₃–H₂O System: Its Potential in CO₂ Sequestration

Gas–Liquid Reactive Crystallization Kinetics of Hydromagnesite in the MgCl₂–CO₂–NH₃–H₂O System: Its Potential in CO₂ Sequestration