Adsorbent material based on passion-fruit wastes to remove lead (Pb), chromium (Cr) and copper (Cu) from metal-contaminated waters

Abstract

The aim of the present work was to evaluate the feasibility of passion-fruit shell (PFS) biomass as adsorbent material to remove heavy metals from contaminated waters. Model mediums were used, which were composed of distilled water and the respective metal: lead (Pb), chromium (Cr) and copper (Cu), with a dose of 10g of dry PFSbiomass per liter of medium. The residual concentration of each metal was determined by Atomic Absorption Spectrophotometry (AAS). A good adsorption capacity was exhibited by this agro industrial waste, achieving removal levels of 96,93 and 82% for Pb, Cr and Cu, respectively. In addition, the results obtained showed an adequate fit to the Freundlich model (R2 > 0.91), on the basis of which, the following values of adsorption capacity (k: 1.7057, 0.6784, 0.3302) and adsorption intensity (n: 0.6869, 2.3474, 1.0499), for Pb, Cr and Cu respectively, were obtained. Our results suggest that Pb, Cr and Cu ions can be removed by more than 80% by using this agro industrial waste, which with a minimum treatment could be used as an adsorbent material in the treatment of metal-contaminated waters.