Retenção do lítio em solos de áreas adjacentes às impactadas pelo rompimento da barragem do Fundão, Mariana – MG

Abstract

The objective of this study was to analyze a sorption of Lithium (Li) in uncontaminated soils from areas adjacent to the tailings of the Fundão Dam, through mathematical models and contact time of the solution and soil, to identify the potential for contamination of the soil and groundwater. Deformed soil samples were collected at a depth of 0 - 20 cm for chemical characterization. Afterwards, air-dried fine earth was weighed and placed in beakers with 20 ml of lithium chloride. Those used were based on current legislation, for class 1, as follows: 2.3; 5.2; 10.1; 20.3; 30.1 and 50.0 mg L-1 of Li. To identify the best contact time between solution and adsorbent, a solution remained at rest (1, 12 and 24 hours) at a constant temperature of 20 °C. Linear, Langmuir and Freundlich isotherms were fitted to obtain experimental curves of the solution. Thus, it uses the coefficient of determination (R2) and the F test. The soil has a low adsorption capacity due to its chemical characteristics, therefore, it is vulnerable to groundwater contamination. The greatest adsorption was within 24 hours and the model with the best fit to the data was Freundlich.