ADSORPTION OF CD(II) AND CU(II) ON ONION BIOMASS (ALLIUM CEPA) FROM AQUEOUS SOLUTION

Copper has a great biological importance in the metabolism of iron by enzymes, but its ingestion in excessive amounts can lead to intoxication, which may cause histopathologies such as hepatic necrosis among others. Cadmium may cause intoxication by inhalation or digestion, and its related physiological effects include severe renal damage, neurological, respiratory and cardiovascular abnormalities. The objective of this work is to develop a natural adsorbent from onion biomass for the removal of heavy metals present in aqueous effluents. The adsorbent was processed through diverse simple stages, until a crude powder with particlesize distribution between 63 μm – 125 μm was obtained. Batch experiments were carried out as a function of time, pH and analyte concentration (to determine the maximum adsorption capacity), and the characterization of this natural adsorbent was performed by point of zero charge (PZC) measurement, infrared spectroscopy analysis (FTIR), X-ray dispersive energy spectroscopy (EDX) and scanning electron microscopy (SEM). The results of the experiments were satisfactory, indicating that the material presents good physico-chemical properties, which allow the adsorption of the metallic ions.