Influence of Acid Contamination on Morphology and Mineralogy of Black Cotton Soil

Abstract

Background: Soil contamination with acids has become a major issue for geotechnical engineers around the globe. Soil contamination with acids can significantly alter the morphology and mineralogy of soil. Thus, in this paper an attempt is made to present the morphological and mineralogical changes occurring in the soil due to prolonged interaction with different concentrations of acid. Methods: In order to assess the effect of acid contamination, a series of sediment volume, scanning electron microscopy and X-ray Diffraction analysis tests were carried out on soil samples which were exposed to three different concentrations of phosphoric and sulphuric acid. Findings: Experimental results show that both acids brought severe morphological changes (trapezoidal structures, needle like structures etc.) and mineralogical changes with the synthesis of neogenic formations mainly at higher concentrations and at prolonged duration of interaction. Improvements: The mineral transformations such as Berilinite, Stilbite, Gypsum, Anhydrite and Albite were found in case of acid contaminated soil which may affect the service conditions of foundations and super structures built on it.