Mining areas produce large amounts of waste that are important sources of potentially toxic elements such as heavy metals to soils, which can contaminate the environment and cause serious threats to the ecosystem and human health. Remediation techniques in situ by adding soil conditioners are efficient and inexpensive alternative to immobilisation of contaminants, which reduces the risks associated with these pollutants. Among the most conditioners used for in situ remediation are phosphate, the alkaline materials and organic compounds. In this project aimed to evaluate the effect of adding conditioners in desorption kinetics and Zn, Cd and Pb speciation in soil of mining area. The soil will be collected in a zinc mining area in the city of Vazante, Minas Gerais, in a mine that is off for more than 15 years. The contaminated soil will be incubated with phosphate, calcium carbonate, biochar and organic fertilizer. After this period will be held chemical characterization and evaluated the desorption kinetics and speciation of metals. Speciation is carried out by absorption spectroscopy x-rays by means of synchrotron light, sequential extraction and ionic speciation of the soil solution. The desorption kinetics will be evaluated after successive extractions with EDTA in eight times and adjusted to the model of double-first order. It is hoped that this experiment information about which phases are controlling the bioavailability of metals in the soil after application of conditioners.
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