CHARACTERIZATION OF CLAY PARTICLE SURFACES FOR CONTAMINANT SORPTION IN SOIL BARRIERS USING FLOW MICROCALORIMETRY

Clays such as kaolinite and bentonite are widely used in various industries as sorbents. The sorptive characteristics of clays are exploited when they are used in contaminant barrier systems. To use clays effectively, their surface characteristics need to be known; especially, when they are used for contaminant sorption. Available surface area of clay minerals and the characteristics that depend on it are very sensitive to environmental changes such as those that can be induced by changes in the composition of pore fluid. Flow microcalorimetry with a down-stream concentration was used to determine the heats and amounts of adsorption of acids and bases on the clays. Test results given herein revealed that both kaolinite and bentonite exhibit very different adsorption isotherms and heat of wetting under high pH and low pH conditions. Kaolinite has the capacity to adsorb both acidic and basic molecules almost equally. However, it has a tendency to adsorb more base than acid because of its stronger complexation capacity with acids than with bases. Conversely, bentonite has a tendency to adsorb more acidic than basic molecules/gram. These results also indicate that both kaolinite and bentonite have different heats of wetting characteristics. As the concentrations of the acids and bases increase, the heat of wetting of kaolinite decreases while that of bentonite increases.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/8675387
• Corporate Authors:

  American Society of Civil Engineers

  1801 Alexander Bell Drive
  Reston, VA  United States  20191-4400
• Authors:
  • Kaya, A
• Publication Date: 2004-8

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 918-921
• Serial:
  • Journal of Environmental Engineering
  • Volume: 130
  • Issue Number: 8
  • Publisher: American Society of Civil Engineers
  • ISSN: 0733-9372
  • Serial URL: http://ojps.aip.org/eeo

Subject/Index Terms

• TRT Terms: Clay; Clay minerals; Embankment foundations; Fine grained soils; Geosynthetics; Kaolinite; Particles; Sorption
• Subject Areas: Geotechnology; Highways; I42: Soil Mechanics;

Filing Info

• Accession Number: 00977759
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 9 2004 12:00AM