THE KINETICS OF ETTRINGITE FORMATION

Three models, mori-minegishi, ginstling-brounshtein, and a nucleation and growth model were analysed in order to investigate the conversion of hemihydrate to gypsum, and ettringite formation in the system c3a-caso4.1/2 h2o-h20 at three hydration temperatures. Analysis of the kinetics of gypsum formation suggests that the rate limiting step changes from an initial dependence on the hemihydrate surface area to a dependence on the gypsum growth rate. The formation of ettringite was found to be controlled by diffusion. In accord with the needle-like morphology that ettringite exhibits, a nucleation and growth model predicted one-dimensional growth. An apparent activation energy calculated for ettringite formation is consistent with a diffusionally controlled process.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00088846
• Corporate Authors:

  Pergamon Press, Incorporated

  Maxwell House, Fairview Park
  Elmsford, NY  United States  10523
• Authors:
  • Brown, P W
  • La Croix, P
• Publication Date: 1989-11

Language

• English

Media Info

• Pagination: p. 879-884
• Serial:
  • Cement and Concrete Research
  • Volume: 19
  • Issue Number: 6
  • Publisher: Elsevier
  • ISSN: 0008-8846
  • Serial URL: http://www.sciencedirect.com/science/journal/00088846

Subject/Index Terms

• TRT Terms: Aluminates; Calcium; Chemical reactions; Diffraction; Gypsum; Hydration; Mathematical models; Sulfates; X rays
• ITRD Terms: 7301: Aluminate; 7178: Calcium; 6779: Diffraction; 4175: Gypsum; 7195: Hydration; 6473: Mathematical model; 7156: Reaction (chem); 7310: Sulphate; 6728: X ray
• Subject Areas: Geotechnology;

Filing Info

• Accession Number: 00498866
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Sep 30 1990 12:00AM