Clays and Clay Minerals

, Volume 41, Issue 6, pp 645–654 | Cite as

The Formation of Illitic Clays from Kaolinite in KOH Solution from 225°C to 350°C

  • Wuu-Liang Huang


Kaolinite was converted into illitic clays in a 2.58 m KOH solution in gold capsules using cold-seal pressure vessels at 225°, 250°, 300°, and 350°C and 500 bars. The XRD shows that the major reaction products are illitic clays with no interlayer expandability. The TEM shows that the illitic clays appear mainly platelet-like with a K/Si ratio close to that of muscovite/illite. The extent of the conversion was monitored by measuring the XRD peak ratio of muscovite (illite) and kaolinite in quenched run products. The results reveal that kaolinite converts to muscovite/illite in the KOH solution at an initial rate two to three orders of magnitude faster than that of similar reactions at near-neutral conditions.

Key Words

Illite Illite synthesis Kaolinite Kinetics 


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Copyright information

© The Clay Minerals Society 1993

Authors and Affiliations

  • Wuu-Liang Huang
    • 1
  1. 1.Exxon Production Research CompanyHoustonUSA

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