| dc.description | Se estudió la capacidad de la testa de semilla de Ricinus communis (RC), de Jatropha curcas (JC), estiércoles ovino (EO), bovino (EB) y de conejo (EC), turba (TR), vermicompost (VR), paja de avena (PA) y carbonatita (C) para adsorber Pb, Cd, Zn, Cu y As de soluciones monoelemento. RC adsorbió Pb (94.8%-98.1%); EB y EC removieron Cd (88.2%-95.4%). VR removió la mayor concentración de Zn (85.3%-99.5%). TR, VR y C fueron las enmiendas que más adsorbieron Cu (94.2%-99.9%). Cascarilla de Ricinus, EB y C adsorbieron más As (44.1%-90.8%). La ecuación de Freundlich simuló bien la adsorción de Cd en EB, EC y TR; de Zn en RC, JC, TR, PA y C; de Cu en RC y PA. La retención de Zn en EB, EC y VR; de Cu en TR; de As en RC, JC, EB, VR y C se ajustó adecuadamente a la ecuación de Langmuir. La concentración soluble de Pb, Cd, Zn, Cu y As en lixiviado ácido de mina (0.2, 1, 159, 7.2 y 44.8 mg kg-1, respectivamente) cambió por la adición de enmiendas. VR (200 g L-1): adsorbió 18.5% y C 83.2% de Pb, así como Cd 16.5% y 96.5%, respectivamente. Carbonatita removió Zn (91.3%) y Cu (99.8%). El As se adsorbió en la misma proporción en todas las enmiendas (88.4%-93.9%). Las concentraciones extractables de Pb, Cd, Zn, Cu y As (33.5, 1.6, 138.4, 8.1 y 41.6 mg kg-1, respectivamente) en el residuo de mina cambiaron por la adición de enmienda: VR adsorbió con más eficiencia Pb (48.3%-57%). Se redujo la disponibilidad de Cd (14.9%-30%), Zn (12%-37.8%) y Cu (15.6%-36.8%) por la aplicación de VR y C. La disponibilidad de As disminuyó por aplicación la de EC (14.9%) y VR (53.6%). Los ácidos húmicos y fúlvicos (H85) aumentaron la disponibilidad de Cd, Zn y Cu, pero, disminuyeron el As extractable. Los factores de bioacumulación de Pb, Cd, Zn, Cu y As en trébol rojo (Trifolium pratense) fueron superiores a 1 (As>Pb>Cd>Cu>Zn). La translocación de Cu y As fue alta (FT > 1). _______________ SORPTION OF POTENTIALLY TOXIC ELEMENTS AFTER AMENDMENTS TREATMENT. ABSTRACT: Lead, Cd, Zn, Cu and As adsorption capacity of Ricinus communis husk (RC), Jatropha curcas husk (JC), sheep manure (EO), cattle manure (EB), rabbit manure (EC), peat moss (TR), vermicompost (VR), oats straw (PA) and carbonatite (C) from aqueous solution was measured. RC adsorbed high concentration of Pb (94.8%-98.1%); EB and EC removed Cd (88.2%-95.4%), followed by VR for Zn adsorption (85.3%-99.5%). TR, VR, and C adsorbed up to (94.2%-99.9%) of Cu, and (44.1%-90.8%) of As on RC, EB, C. The Freundlich equation fit well Cd adsorption on EB, EC, and TR; Zn adsorption on RC, JC, TR, PA, and C; Cu adsorption on RC and PA. However, Zn adsorption on JC, EB, EC, and VR. Cu retention on TR, and As adsorption on RC, JC, EB, VR, and C was fairly well fit using the equation of Langmuir. Biosorption of metals on EO, EB, EC, VR, and C from acid mine drainage was tested in the following doses 50, 100, and 200 g L-1. The initial Pb, Cd, Zn, Cu and As concentrations decreased from 0.2, 1, 159, 7.2 and 44.8 mg kg-1, respectively, as follows: 18.5% of Pb on VR, (83.2%) on C. VR adsorbed 16.5% of Cd and C removed 96.5%. Carbonatite removed Zn (91.3%) and Cu (99.8%), respectively. Arsenic was removed in the same percentage by the biosorbents (88.4%-93.9%). The DPTA extractable concentrations of Pb, Cd, Zn, Cu and As (33.5, 1.6, 138.4, 8.1 y 41.6 mg kg-1, respectively) in the mine residues was depleted by selected biosorbents: VR reduces Pb (48.3%-57%); Cd (14.9%-30%), Zn (12%-37.8%), and Cu (15.6%-36.8%) concentrations. Extractable As decreased (14.9%) by EC addition, and (53.6%) by VR. Humic and fulvic acids (H85) increased extractable As. The bioaccumulation factors of Pb, Cd, Zn, Cu, and As in Trifolium pratense was over 1. The accumulation concentration in shoots was As>Pb>Cd>Cu>Zn. The TF over 1 was observed for Cu and As. | |
