Determinación de cobre y níquel en muestras de lodo y agua de la vertiente de Villapinzón del Río Bogotá, por espectrofotometría de absorción atómica

Abstract

The Bogota river (Colombia) has been contaminated since its source in the township of Villapinzón by tanneries located in its riverbed, which generate wastes as heavy metal residues; of which studies have been reported for chromium, lead and mercury during the last years; however metals such as copper and nickel are not named, which is why the present study identifies the heavy metals copper and nickel in water matrices and residual sludge of the Bogotá river in the slope of Villapinzon (Coordinates: 5°12'40.6"N 73°36'02.7"W), by the technique of atomic absorption. For the determination, a composite sampling was performed as a function of time, the organic matter present in the samples was eliminated by two-way digestion (acid and microwave assisted). The limits of detection and quantification were determined for each metal, being for Copper: LOD=0.0002 mg/L and LOQ=0.0015 mg/L; and for Nickel: LOD=0.0005 mg/L and LOQ=0.0012 mg/L. It was also established that: although statistically there is no significant difference between the types of digestion, graphically it is observed that higher concentrations of the metals are found in acid digestion; there are higher concentrations of metals in sludge than in water, there is no correlation between metals in the different matrices, nor between water and sludge for the concentration of the same metal; finally, the concentrations detected for copper and nickel in waters and sludge do not exceed the limits allowed by Colombian regulations for wastewater and biosolids.