Econ. Environ. Geol. 2002; 35(2): 103-112

Published online April 30, 2002

© THE KOREAN SOCIETY OF ECONOMIC AND ENVIRONMENTAL GEOLOGY

Thermodynamic Consideration on the Occurrence of Al13-Tridecamer in the Natural Conditions

Gyoo Ho Lee1, Yungoo Song1*, Hi-Soo Moon1, Ji-Won Moon1 and In-Joon Kim2

1Department of Earth System Sciences, Yonsei University, Seoul 120-749, Korea
2Korea Institute of Geoscience and Mineral Resources, Daejon 305-350, Korea

Correspondence to :

Yungoo Song

yungoo@yonsei.ac.kr

Received: February 20, 2002; Accepted: April 26, 2002

Abstract

Despite the ecological importance of potentially phytotoxic Al13-tridecamer and its formation in the simulated condition, it was not recognized in the natural soil environment. Here we performed thermodynamic calculations to examine the stability condition of Al13-tridecamer based on the solubility of Al in the Bo horizon of Andisols, Jeju Island, dominantly composed of Al-containing solid phases such as Al(OH)3, proto-imogolite and/or imogolite. We have found that Al(OH)3, proto-imogolite and/or imogolite may control Al solubility in the moderate acid condition. It means that Al total activity of the soil solution equilibrated with these solid phases ranges from 10-6~10-8M in the pH 5 to 7. Calculations based on the thermodynamic data strongly indicate that the formation of Al13-tridecamer
closely related to the total activity of Al in the system. For example, for the formation of Al13-tridecamer of 10-5M, Al total activity of 3X10-3M are needed at pH 4, and 2X10-5M in the pH 5 to 7. Therefore, this research and the thermodynamic consideration suggest strongly that Al13-tridecamer should be negligible in natural soils, especially Andisols and Spodosols. These mainly contain Al(OH)3, proto-imogolite and/or imogolite, which could prevent theformation of Al13-tridecamer by controlling the Al total activity low. It means that the toxicity of Al13-tridecamer with the increase of soil acidification may be considered to be definitely low.

Keywords Al13-tridecamer, gibbsite, imogolite, proto-imogolite, soil acidification

Article

Econ. Environ. Geol. 2002; 35(2): 103-112

Published online April 30, 2002

Copyright © THE KOREAN SOCIETY OF ECONOMIC AND ENVIRONMENTAL GEOLOGY.

Thermodynamic Consideration on the Occurrence of Al13-Tridecamer in the Natural Conditions

Gyoo Ho Lee1, Yungoo Song1*, Hi-Soo Moon1, Ji-Won Moon1 and In-Joon Kim2

1Department of Earth System Sciences, Yonsei University, Seoul 120-749, Korea
2Korea Institute of Geoscience and Mineral Resources, Daejon 305-350, Korea

Correspondence to:

Yungoo Song

yungoo@yonsei.ac.kr

Received: February 20, 2002; Accepted: April 26, 2002

Abstract

Despite the ecological importance of potentially phytotoxic Al13-tridecamer and its formation in the simulated condition, it was not recognized in the natural soil environment. Here we performed thermodynamic calculations to examine the stability condition of Al13-tridecamer based on the solubility of Al in the Bo horizon of Andisols, Jeju Island, dominantly composed of Al-containing solid phases such as Al(OH)3, proto-imogolite and/or imogolite. We have found that Al(OH)3, proto-imogolite and/or imogolite may control Al solubility in the moderate acid condition. It means that Al total activity of the soil solution equilibrated with these solid phases ranges from 10-6~10-8M in the pH 5 to 7. Calculations based on the thermodynamic data strongly indicate that the formation of Al13-tridecamer
closely related to the total activity of Al in the system. For example, for the formation of Al13-tridecamer of 10-5M, Al total activity of 3X10-3M are needed at pH 4, and 2X10-5M in the pH 5 to 7. Therefore, this research and the thermodynamic consideration suggest strongly that Al13-tridecamer should be negligible in natural soils, especially Andisols and Spodosols. These mainly contain Al(OH)3, proto-imogolite and/or imogolite, which could prevent theformation of Al13-tridecamer by controlling the Al total activity low. It means that the toxicity of Al13-tridecamer with the increase of soil acidification may be considered to be definitely low.

Keywords Al13-tridecamer, gibbsite, imogolite, proto-imogolite, soil acidification

    KSEEG
    Jun 30, 2024 Vol.57 No.3, pp. 281~352

    Stats or Metrics

    Share this article on

    • kakao talk
    • line

    Related articles in KSEEG

    Economic and Environmental Geology

    pISSN 1225-7281
    eISSN 2288-7962
    qr-code Download