1. Cation interception and permeability characteristics of bentonite barriers exposed to NaCl and NH 4 Cl solutions.
- Author
-
Sun WJ, Tang QT, Fan RD, Yang AW, Tan YZ, and Leung AK
- Subjects
- Ammonium Chloride chemistry, Cations, Water Pollutants, Chemical chemistry, Bentonite chemistry, Sodium Chloride chemistry, Permeability
- Abstract
High concentrations of Na
+ and NH4 + in landfill leachate lead to deterioration of bentonite barrier and pose a threat to the environment. This study focused on the pollution interception and permeability characteristics of the bentonite barrier exposed to NaCl and NH4 Cl solutions. Based on previous findings, salt solution concentrations were established at 74.80, 37.40, 18.70, and 9.4 mmol/L. The bentonite contents in the mixture were set at 0, 5, 10, and 15%. The results indicate that the samples exhibit better interception of NH4 + compared to Na+ . This difference arises from the cation exchange sequence, the size of the hydration radius, and the hydrogen bonding of the two cations. Additionally, the difference in hydration enthalpy between the two cations leads to variations in the swelling of bentonite, resulting in a higher hydraulic conductivity coefficient in NH4 Cl solution. This study shows that although bentonite barriers have better interception for NH4 + , they exhibit greater hydraulic conductivity in NH4 Cl solution, increasing the risk of leachate carrying other contaminants., Competing Interests: The authors declare there is no conflict., (© 2024 The Authors This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY-NC-ND 4.0), which permits copying and redistribution for non-commercial purposes with no derivatives, provided the original work is properly cited (http://creativecommons.org/licenses/by-nc-nd/4.0/).)- Published
- 2024
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