نوع مقاله : مقاله کامل پژوهشی
نویسندگان
1 عضو هیئت علمی دانشگاه بوعلی سینا و عضو هیئت علمی وابسته دانشکده عمران دانشگاه تهران
2 دانشکده مهندسی دانشگاه بوعلی سینا
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Bentonite is commonly used as a liner in landfills. Sodium-bentonite and calcium-bentonite are among the useful materials for this purpose. On the other hand, in several cases, clayey soils are exposed to high temperatures in engineering and geo-environmental engineering projects. Despite several types of research on the interaction of heavy metals and clayey soils, there is a lack of research on the mutual effect of temperature and double layer cation type on the adsorption of heavy metals in clayey soil. Therefore, the main objective of this paper is to investigate the impact of temperature and type of double-layer cation on the adsorption of copper heavy metal by bentonite. Calcium chloride salt was used to make homo-ionic bentonite to achieve the above-mentioned objective. Several geoenvironmental engineering experiments were performed to address and achieve the above-mentioned objective.
According to the results of this paper, in sodium-bentonite samples, due to the presence of sodium ions in clay double-layer, the soil behavior is noticeably function of de-hydroxylation at temperatures above 600 degrees centigrade. At 400 to 600 degrees centigrade and above, the major mechanism for contaminant retention is the existence of carbonate in soil. This emphasizes the importance of carbonate in clayey soils to have a stable buffering capacity at high temperatures. In addition, the change in the intensity of the major peak of montmorillonite at 600 degrees centigrade and above is independent of the type of double-layer cations.
کلیدواژهها [English]
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