Effects of the structure of silica-alumina gel on the hydrothermal synthesis of kaolinite

Shigeo Satokawa, Yasushi Osaki, Soichiro Samejima, Ritsuro Miyawaki, Shinji Tomura, Yasuo Shibasaki, Yoshiyuki Sugahara

    Research output: Contribution to journalArticle

    23 Citations (Scopus)

    Abstract

    Kaolinite was hydrothermally synthesized from two kinds of silica-alumina gels to examine the effect of the structure of the starting material. Two kinds of gels were prepared by precipitation at different pH conditions (pH = 9.6 and 4.2) from solutions containing water glass and aluminum sulfate. Na ions in the gels were removed with a resin before the hydrothermal treatment, but a slight amount of sulfate ions was still present in the gels. The nuclear magnetic resonance spectra of the starting gels suggested that the gel prepared at pH 9.6 consists of networks with alternating SiO4- and AlO4-tetrahedra (partially AlO6-octahedra), whereas the gel prepared at pH 4.2 consists of a sheet structure related to allophane. After the hydrothermal treatment at 220°C for 9 days, kaolinite particles with spherical shape were obtained from the former gel, and platy kaolinite was crystallized from the latter one. The difference in morphology of synthetic kaolinite was attributable to the structures of the starting gels, and the pH values in the hydrothermal reactions were not very significant to the morphology.

    Original languageEnglish
    Pages (from-to)288-297
    Number of pages10
    JournalClays and Clay Minerals
    Volume42
    Issue number3
    DOIs
    Publication statusPublished - 1994

    Fingerprint

    Kaolin
    aluminum oxide
    Aluminum Oxide
    Hydrothermal synthesis
    kaolinite
    Silicon Dioxide
    silica
    gel
    Gels
    gels
    synthesis
    hot water treatment
    Ions
    ions
    sulfate
    aluminum sulfate
    allophane
    effect
    ion
    Sulfates

    Keywords

    • Gel structure
    • Hydrothermal synthesis
    • Kaolinite
    • Nuclear magnetic resonance
    • Silica-alumina gel

    ASJC Scopus subject areas

    • Soil Science
    • Earth and Planetary Sciences (miscellaneous)
    • Geochemistry and Petrology
    • Water Science and Technology
    • Earth and Planetary Sciences(all)
    • Environmental Science(all)

    Cite this

    Effects of the structure of silica-alumina gel on the hydrothermal synthesis of kaolinite. / Satokawa, Shigeo; Osaki, Yasushi; Samejima, Soichiro; Miyawaki, Ritsuro; Tomura, Shinji; Shibasaki, Yasuo; Sugahara, Yoshiyuki.

    In: Clays and Clay Minerals, Vol. 42, No. 3, 1994, p. 288-297.

    Research output: Contribution to journalArticle

    Satokawa, S, Osaki, Y, Samejima, S, Miyawaki, R, Tomura, S, Shibasaki, Y & Sugahara, Y 1994, 'Effects of the structure of silica-alumina gel on the hydrothermal synthesis of kaolinite', Clays and Clay Minerals, vol. 42, no. 3, pp. 288-297. https://doi.org/10.1346/CCMN.1994.0420307
    Satokawa, Shigeo ; Osaki, Yasushi ; Samejima, Soichiro ; Miyawaki, Ritsuro ; Tomura, Shinji ; Shibasaki, Yasuo ; Sugahara, Yoshiyuki. / Effects of the structure of silica-alumina gel on the hydrothermal synthesis of kaolinite. In: Clays and Clay Minerals. 1994 ; Vol. 42, No. 3. pp. 288-297.
    @article{0ca76af92ec840fc89638d4dd047802b,
    title = "Effects of the structure of silica-alumina gel on the hydrothermal synthesis of kaolinite",
    abstract = "Kaolinite was hydrothermally synthesized from two kinds of silica-alumina gels to examine the effect of the structure of the starting material. Two kinds of gels were prepared by precipitation at different pH conditions (pH = 9.6 and 4.2) from solutions containing water glass and aluminum sulfate. Na ions in the gels were removed with a resin before the hydrothermal treatment, but a slight amount of sulfate ions was still present in the gels. The nuclear magnetic resonance spectra of the starting gels suggested that the gel prepared at pH 9.6 consists of networks with alternating SiO4- and AlO4-tetrahedra (partially AlO6-octahedra), whereas the gel prepared at pH 4.2 consists of a sheet structure related to allophane. After the hydrothermal treatment at 220°C for 9 days, kaolinite particles with spherical shape were obtained from the former gel, and platy kaolinite was crystallized from the latter one. The difference in morphology of synthetic kaolinite was attributable to the structures of the starting gels, and the pH values in the hydrothermal reactions were not very significant to the morphology.",
    keywords = "Gel structure, Hydrothermal synthesis, Kaolinite, Nuclear magnetic resonance, Silica-alumina gel",
    author = "Shigeo Satokawa and Yasushi Osaki and Soichiro Samejima and Ritsuro Miyawaki and Shinji Tomura and Yasuo Shibasaki and Yoshiyuki Sugahara",
    year = "1994",
    doi = "10.1346/CCMN.1994.0420307",
    language = "English",
    volume = "42",
    pages = "288--297",
    journal = "Clays and Clay Minerals",
    issn = "0009-8604",
    publisher = "Clay Minerals Society",
    number = "3",

    }

    TY - JOUR

    T1 - Effects of the structure of silica-alumina gel on the hydrothermal synthesis of kaolinite

    AU - Satokawa, Shigeo

    AU - Osaki, Yasushi

    AU - Samejima, Soichiro

    AU - Miyawaki, Ritsuro

    AU - Tomura, Shinji

    AU - Shibasaki, Yasuo

    AU - Sugahara, Yoshiyuki

    PY - 1994

    Y1 - 1994

    N2 - Kaolinite was hydrothermally synthesized from two kinds of silica-alumina gels to examine the effect of the structure of the starting material. Two kinds of gels were prepared by precipitation at different pH conditions (pH = 9.6 and 4.2) from solutions containing water glass and aluminum sulfate. Na ions in the gels were removed with a resin before the hydrothermal treatment, but a slight amount of sulfate ions was still present in the gels. The nuclear magnetic resonance spectra of the starting gels suggested that the gel prepared at pH 9.6 consists of networks with alternating SiO4- and AlO4-tetrahedra (partially AlO6-octahedra), whereas the gel prepared at pH 4.2 consists of a sheet structure related to allophane. After the hydrothermal treatment at 220°C for 9 days, kaolinite particles with spherical shape were obtained from the former gel, and platy kaolinite was crystallized from the latter one. The difference in morphology of synthetic kaolinite was attributable to the structures of the starting gels, and the pH values in the hydrothermal reactions were not very significant to the morphology.

    AB - Kaolinite was hydrothermally synthesized from two kinds of silica-alumina gels to examine the effect of the structure of the starting material. Two kinds of gels were prepared by precipitation at different pH conditions (pH = 9.6 and 4.2) from solutions containing water glass and aluminum sulfate. Na ions in the gels were removed with a resin before the hydrothermal treatment, but a slight amount of sulfate ions was still present in the gels. The nuclear magnetic resonance spectra of the starting gels suggested that the gel prepared at pH 9.6 consists of networks with alternating SiO4- and AlO4-tetrahedra (partially AlO6-octahedra), whereas the gel prepared at pH 4.2 consists of a sheet structure related to allophane. After the hydrothermal treatment at 220°C for 9 days, kaolinite particles with spherical shape were obtained from the former gel, and platy kaolinite was crystallized from the latter one. The difference in morphology of synthetic kaolinite was attributable to the structures of the starting gels, and the pH values in the hydrothermal reactions were not very significant to the morphology.

    KW - Gel structure

    KW - Hydrothermal synthesis

    KW - Kaolinite

    KW - Nuclear magnetic resonance

    KW - Silica-alumina gel

    UR - http://www.scopus.com/inward/record.url?scp=0028583196&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=0028583196&partnerID=8YFLogxK

    U2 - 10.1346/CCMN.1994.0420307

    DO - 10.1346/CCMN.1994.0420307

    M3 - Article

    VL - 42

    SP - 288

    EP - 297

    JO - Clays and Clay Minerals

    JF - Clays and Clay Minerals

    SN - 0009-8604

    IS - 3

    ER -