EXPERIMENTAL-STUDY OF ALUMINUM AND CALCIUM MALONATE COMPLEXATION AT 25-DEGREES-C, 35-DEGREES-C, AND 80-DEGREES-C

被引：8

作者：

FEIN, JB

YANE, L

JYOTI, A

HANDA, T

机构：

来源：

GEOCHIMICA ET COSMOCHIMICA ACTA | 1995年 / 59卷 / 06期

基金：

加拿大自然科学与工程研究理事会;

关键词：

D O I：

10.1016/0016-7037(95)00022-R

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

The solubility of gibbsite was measured at 35 and 80-degrees-C, and the solubility of portlandite was measured at 25, 35, and 80-degrees-C, each as a function of pH and malonate concentration. The gibbsite solubility data can be satisfactorily modelled using only one aqueous Al-malonate species. The data rule out all possible Al(p) (OH)q (Mal)r 3p-q-2r) and Al(p)(OH)q (HMal)r 3p-q-r) stoichiometries except Al(Mal)2- and Al(Mal)2- is the dominant species, the data constrain the value for the log of the dissociation constant of Al(Mal)2- to be -11.3 +/- 1.0 and -14.5 +/- 0.5 at 35 and 80-degrees-C, respectively. If Al(OH)2 (HMal)2- is the dominant species, the values of its dissociation constant at 35-degrees-C and at 80-degrees-C are -27.3 +/- 1.0 and -27.6 +/- 0.5, respectively. The portlandite solubilities indicate that that Ca(Mal)0 is the dominant Ca-malonate complex, with values for the log of the dissociation constant of Ca(Mal)0 of -2.4 +/- 0.3, -2.4 +/- 0.3, and -2.9 +/- 0.3, at 25, 35, and 80-degrees-C, respectively. Thermodynamic modelling, using these results, indicates that Al-malonate complexation can potentially enhance the solubility of Al-bearing minerals by up to five orders of magnitude.

引用

页码：1053 / 1062

页数：10

共 27 条

[1]

Baes, Mesmer, The Hydrolysis of Cations, (1976)

[2]

Bloom, Weaver, Effect of the removal of reactive surface material on the solubility of synthetic gibbsites, Clays Clay Mineral., 30, pp. 281-286, (1982)

[3]

Busey, Mesmer, Thermodynamic quantities for the ionization of water in sodium chloride media to 300°C, J. Chem. Eng. Data, 23, pp. 175-176, (1978)

[4]

Couturier, Michard, Sarazin, Constantes de formation des complexes hydroxydés de l'aluminium en solution aqueuse de 20 à 70°C, Geochim. Cosmochim. Acta, 48, pp. 649-659, (1984)

[5]

Crossey, Thermal degradation of aqueous oxalate species, Geochim. Cosmochim. Acta, 55, pp. 1515-1527, (1991)

[6]

Fein, Experimental study of aluminum-oxalate complexing at 80°C: Implications for the formation of secondary porosity within sedimentary reservoirs, Geology, 19, pp. 1037-1040, (1991)

[7]

Fein, Experimental study of Al-, Ca-, and Mg-acetate complexing at 80°C, Geochim. Cosmochim. Acta, 55, pp. 955-964, (1991)

[8]

Fein, Hestrin, Experimental studies of oxalate complexation at 80°C: Gibbsite, amorphous silica, and quartz solubilities in oxalate-bearing fluids, Geochim. Cosmochim. Acta, 58, pp. 4817-4829, (1994)

[9]

Fein, Yane, Handa, The effect of aqueous complexation on the decarboxylation rate of oxalate, Geochim. Cosmochim. Acta, 58, pp. 3975-3982, (1994)

[10]

Ghosh, Nair, Studies on metal complexes in aqueous solution. II. Malonates and phthalates of copper and calcium, J. Inorg. Nucl. Chem., 32, pp. 3033-3039, (1970)

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