Rezumat
This paper reports the interaction between clay and acidic wastewater (pH=2.7 and rich in F-, PO43-, Cl-…). However, this work investigates the structural and textural evolution after the leachate permeability test of clay soils from three potentials sites for acid effluents storage in the south of Tunisia (Soil-1, Soil-2 and Soil-3). We can notice, that the coefficient of permeability decreases according to time in the case of soil-1 and soil-2 and increase from 6.8 10-10 to 1.1 10-8 m/s for soil-3. The textural changes for the three varieties of clay soils obtained after leachate permeability test were studied through nitrogen gas adsorption at liquid nitrogen temperature; we determined the specific surface areas (SBET), total pore and micropore volume. The textural study data have indicated that the soil-1 had lowest textural properties with a pore volume in the 0.06-0.09 cm 3 g-1 ranges and with a surface area (SBET) vary between 35.4 and 47.4 m2g-1. A detailed structural and morphologic modification were undertaken by scanning electron microscopy (SEM) equipped by an energy–dispersive spectroscopy (EDS), their results shows that soil-1 and soil-2 able to uptake the noxious elements. By comparison, the selectivity of eliminate these elements are in this order F>P>S for soil1. The quantitative analysis of anions shows that the sorption capacity of fluoride for soil-1 is about 60mg/g and is very higher comparing to others anions.