Estudio comparativo de dos sistemas de filtrado a base de residuos orgánicos de huevo y naranja para la retención de cromo hexavalente (Cr+6) de soluciones acuosas

Abstract

The aim of this project was to carry out a comparative study of the hexavalent chromium retention in synthetic water using an eggshell organic waste-based filter and another orange peel-based filter. Each filter was built in a PVC container with a height of 18cm and a diameter of 10cm, where two layers of granular filtering media (gravel and sand) as well as a 100g layer of biomaterial were placed. To determine the elimination level, the initial concentration of chromium solution and the type of biosorbent were analyzed, keeping a constant neutral pH (7-7.5) and a contact time of 120 min. The quantification of hexavalent chromium was performed through ultraviolet visible absorption spectrometry at a wavelength of 540 nm. The analyses revealed that the most effective retention rates reflected the orange peel filter, with values of 81.33%, 92.50%, 93.20% and 96.04% at concentrations of 0.6, 0.8, 1 and 1.5 ppm, respectively; in contrast to the eggshell filter, where 46%, 47.75%, 55.90% and 56.06% were retained at the same concentrations of hexavalent chromium as mentioned above. From the results, it is concluded that orange peel filters are more efficient because they reuse waste; thus, they are cheaper and environmentally friendly. Further experimental studies of these biomaterials are recommended in order to find the most appropriate method that allows obtaining better efficiency in the removal of hexavalent chromium and other metals.