Resumen

AVILES, María et al. Study of the chelating effect of natural clay filters over heavy metals; Pb and Hg for their application in remediation of soils, wáter conservation and biodiversity. Rev. Cien. Tec. In. [online]. 2018, vol.16, n.17, pp. 875-982. ISSN 2225-8787.

Abstract The aim of this study was to determine the chelator effect of natural clay filters on the heavy metals lead and mercury, to assist in remediation and conservation of soil, water and biological diversity of ecosystems likely to be contaminated by mining discharges. The assessed variables were: the heavy metal chelation by clay filters prior to treatment with chelating agent (EDTA) and without chelating agent. The chelating capacity of the clay was preliminary evaluated by measuring the amount of heavy metal trapped in the clay; in general, it was observed that the chelating capacity of the clay pretreated (laboratory tests) showed a better chelating effect on the heavy metals: lead (Pb) and mercury (Hg), obtaining an average of 748.5 mg Pb / kg for lead in relation to the average obtained from the sample without a chelating agent (739 mg Pb / kg of Clay). In the same way was performed for the case of mercury (Hg), the result was higher for the pretreated clay with chelating agent, obtaining an average result of 729 mg Hg / kg dry weight of clay and the result for the untreated sample was 715 mg/kg. The data were statistically analyzed by setting up a t-test (One-factor ANOVA) using Statistical Package for Social Sciences (SPSS 11.5), the results obtained demonstrated that the chelating effect of the clay on heavy metals, influences the treatment independently with or without chelating agent, so that there are not significant differences. Chelation of heavy metals (lead), F (1,2) = 6.811 p; 0.121 and (mercury) F (1,2) = 10.889 p; 0.081 (higher probability of 0.05 no significant differences).

Palabras llave : Metals; lead; mercury; chelation; clay; conservation.