Aluminosilicate cation exchange compounds

Chemistry of inorganic compounds – Silicon or compound thereof – Oxygen containing

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4233282, C01B 3326

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active

059583541

DESCRIPTION:

BRIEF SUMMARY
TECHNICAL FIELD

This invention relates to aluminosilicate compounds which have cation exchange capacity and is particularly concerned with such materials having a stuffed silica polymorph-related structure in which the aluminium is tetrahedrally coordinated.


BACKGROUND ART

Kalsilite, nepheline, carnegieite and eucryptite are all crystalline minerals of ideal composition MAlSiO.sub.4, where M is an alkali metal, having a stuffed silica polymorph-related structure in which the aluminium is tetrahedrally coordinated.
Kalsilite has ideal composition KAlSiO.sub.4, while nepheline exists as a solid-solution and has the composition Na.sub.1-x K.sub.x AlSiO.sub.4, where O.ltoreq.x<1. Both of these minerals have crystal structures closely related to that of the silica polymorph, tridymite (see FIG. 1). Carnegieite has ideal composition NaAlSiO.sub.4 and has a crystal structure closely related to that of the silica polymorph, cristobalite (see FIG. 2). Eucryptite has ideal composition LiAlSiO.sub.4 and has a crystal structure closely related to that of the silica polymorph, quartz (see FIG. 3).
Tridymite, cristobalite and quartz all have the composition SiO.sub.2 and consist of a 3-dimensional framework of corner-connected SiO.sub.4 tetrahedra. Kalsilite, nepheline, carnegieite and eucryptite have been described as stuffed derivatives of the tridymite, cristobalite or quartz structures, in that half of the silica cations in the silicate framework in each case are replaced by aluminium cations. Alkali cations, which are required for charge balance (Si.sup.4+ <-->Al.sup.3+ +M.sup.+, M=alkali) occupy the interstices in the respective frameworks (see FIGS. 1-3)--hence the descriptions "stuffed tridymite", "stuffed cristobalite", and "stuffed quartz".
In kalsilite, nepheline, carnegieite andeucryptite, the interstitial cations, M.sup.+, are not exchangeable under normal conditions, that is, in aqueous salt solution at atmospheric pressure up to -100.degree. C. Therefore, kalsilite, nepheline, carnegieite and eucryptite have negligible cation exchange capacity (CEC). Any CEC is associated with the surface of crystals and not the bulk of the structure.
It has been proposed in, for example, Roux, J., 1971, C. R. Acad. Sci., Ser. D 272, 3225-3227 to exchange the interstitial cations of kalsilite and related aluminosilicates by treating the material at high temperature and pressure under hydrothermal conditions.
It has also been proposed by Sobrados & Gregorkiewitz, 1993, Physics and Chemistry of Minerals, 20, 433-441 to achieve similar exchange of cations by treating kalsilite and related materials with molten salts such as MNO.sub.3 or MCl (M=Li, Na, K, Ag).
However, it is widely accepted that aluminosilicates with the stuffed tridymite-type structure have no cation exchange capacity associated with the bulk structure, either in aqueous solution or in organic solvents.
It has been proposed in, for example, Petranovic et al, 1991, Materials Science Monograph, 666, 2229-2236, that it is possible to exchange the interstitial Na.sup.+ cation of carnegieite with Li.sup.+ by treating it with molten LiNO.sub.3. Associated with this ability to exchange cations by treatment with molten salts is the property of ionic conductivity which has been observed for carnegieite and related materials.
It is also expected that, as for kalsilite and nepheline, exchange of the interstitial cations might be induced under aqueous conditions provided that the material were subjected to sufficiently high temperatures and pressures, i.e. under hydrothermal conditions.
However, it is widely accepted that aluminosilicates with the stuffed cristobalite-type structure have no cation exchange capacity associated with the bulk structure, either in aqueous solution or in organic solvents.
It has been proposed in, for example, Berchot et al, 1980, Journal of Solid State Chemistry, 34, 199-205, that while it is not possible to substitute Li.sup.+ in .beta.-eucryptite by treatment using molten salts with bigger cations such as Na.sup.+, K+ or Ag.su

REFERENCES:
patent: 3586523 (1971-06-01), Fanselow et al.
patent: 3663456 (1972-05-01), Upson
Natale et al., "Solid State Reaction of Sodium Carbonate with Montmorillonite at 550.degree. C. ," Chemical Abstracts, 110(19):685 (Abstract No.: 172201x (1989)(No Month).
Natale et al., "Solid State Reaction of Sodium Carbonate with Montmorillonite at 550.degree. C.," Clays Clay Miner., 37(1):89-95 (1989)(No Month).
MacKenzie et al., "Outstanding Problems in the Kaolinite-Mullite Reaction Sequence Investigated by .sup.29 Si and .sup.27 Al Solid-State Nuclear Magnetic Resonance: I, Metakaolinite," Journal of the American Ceramic Society, 68(6):293-297 (1985)(No Month).
Lambert et al., "Revisiting Kaolinite Dehydroxylation: A .sup.29 Si and .sup.27 Al MAS NMR Study," J. Am. Chem. Soc., 111:3517-3522 (1989)(No Month).
Berchot et al., "Ion Exchange Properties of .beta.-Eucryptite (LiAlSiO.sub.4): EPR Investigation on Copper-Doped Single Crystals," Journal of Solid State Chemistry, 34:199-205 (1980)(No Month).
Buerger, "The Stuffed Derivatives of the Silica Structures," American Mineralogist, 39:600-614 (1954)(No Month).
Dondur et al., "High Temperature Transformations of NH.sub.4 A Zeolite", Thermochimica Acta, 93:753-756 (1985)(No Month).
Goodenough et al., "Fast Na.sup.+ -Ion Transport In Skeleton Structures," Mat. Res. Bull., 11:203-220 (1976)(No Month).
Kubo et al., "Reaction Processes to Form Nepheline-Carnegieite Minerals from Various Starting Materials," Mineralogical Journal, 5(3):213-223 (1967)(No Month).
Murat, "Thermal Evolution of Type 4A Synthetic Zeolites. Influence of Composition on Heterogeneities on the Manifestation of Exothermic Effects at 800-1000.degree. C.," Journal of Thermal Analysis, 4:73-81 (1972)(No Month).
Petranovic et al., "Kinetic Study of Phase Transition in the System LiAlSiO.sub.4," Ceramics Today--Tomorrow's Ceramics, pp. 2229-2236 (1991)(No Month).
Roux, "Eqilibrium of the Exchange Reaction of Sodium-Potassium Ions in Nepheline at 600.degree. C. and 2000bar," C.R. Acad. Sci. Ser. D, 272:3225-3227 (1971)(No Month).
Schairer, "Melting Relations of the Common Rock-Forming Oxides," Journal of the American Ceramic Society, 40(7):215-230 (1957)(Jul.)
Schmitz et al., "Thermal Decomposition of Partially Mg.sup.2+ -Exchanged Forms of Zeolite A Investigated by DTA-and X-Ray High Temperature Methods," Crystal Research and Technology, 16(3):385-389 (1981)(No Month).
Shannon, "Ionic Conductivity in Sodium Magnesium Silicates," Phys. Chem. Minerals, 4:139-148 (1979)(No Month).
Shannon and Berzins, "Ionic Conductivity in Low Carnegieite Compositions Based on NaAlSiO.sub.4," Materials Research Bulletin, 14:361-367 (1979)(No Month).
Sobrados and Gregorkiewitz, "Ion Exchange Between Tectosilicates with the Nephelin-Kalsilite Framework and Molten MNO.sub.3 or Mcl (M-Li, Na, K, Ag)," Phys. Chem. Minerals, 20:433-441 (1993)(No Month).
West, Solid State Chemistry and its Applications, pp. 5-7 No Date.
Thompson et al., "The Intercalation of Kaolinite by Alkali Halides in the Solid State: A Systematic Study of the Intercalates and Their Derivatives," Clays and Clay Minerals, 41(1):73-86 (1993)(No Month).
Thompson et al., "Structural Characterisation of Kaolinite:NaCl Intercalate and Its Derivatives," Clays and Clay Minerals, 40(4):369-380 (1992)(No Month).
Heller-Kallai, "Reaction of Salts with Kaolinite at Elevated Temperatures," Clay Minerals, 13:221-235 (1978)(No Month).
Gabor et al., "Interaction of Kaolinite with Organic and Inorganic Alkali Metal Salts at 25-1300.degree. C.," Thermochimica Acta, 128:431-438 (1989)(No Month).
Brindley, "Thermal Transformations of Clays and Layer Silicates," Proceedings of teh International Clay Conference, Applied Publishing: Illinois, pp. 119-129 (1975)(No Month).
Rocha and Klinowski, ".sup.29 Si and .sup.27 Al Magic-Angle-Spinning NMR Studies of the Thermal Transformation of Kaolinite," Phys. Chem. Minerals, 17:179-186 (1990)(No Month).
Meinhold et al., "Thermal Reactions of Kaolinite Studied by Solid State 27-Al a

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