Use of an environmental pollutant from hexavalent chromium removal as a green catalyst in the fenton process

Abstract

The present study refers to the use of an environmental pollutant generated during the removal of hexavalent chromium from aqueous media. This pollutant is a material with catalytic properties suitable for application in the oxidative degradation of problematic organic compounds. The material, initially used as an adsorbent, is a composite prepared by modifying the crystalline phases of iron oxides together with the chitosan (CT-FeCr). Chemical and morphological characterizations of the materials were performed using SEM analysis coupled with EDS, XRD and DSC. The CT-FeCr beads were used in the degradation of methylene blue dye (MB) and showed excellent degradation potential (93.6%). The presence of Cr on the surface of the catalyst was responsible for the increase in catalytic activity compared to the CT-Fe and pure magnetite materials. The product of the effluent treatment and the presence of the catalyst itself in the environment do not pose toxic effects. In addition, the CT-FeCr beads showed catalytic stability for several consecutive reaction cycles with possible technical and economic viability. The concept of “industrial symbiosis” may be applied to this technology, with that term relating to the reuse of a byproduct generated in one particular industrial sector by another as a raw material.