Aplicação e caracterização de carepa de aço com carvão ativado no tratamento de 2,4-dinitrofenol em reator de leito fixo

Abstract

In general, conventional treatments are not enough to effectively treat industrial effluents, making it necessarytoinvest in new techniques that perform more eficientely and at a lower cost. Advanced oxidatives processes (AOPS) are Technologies that have already proved efficient in the adequate treatment of several types of emerging pollutants through the generation of hydroxylradicals, species with high oxidation Power that are able to mineralize a wide range of pollutants in a non-selective manner. The combination of hydrogen peroxide with ferrous ions triggers a classicr eaction between the AOPs,the homogeneous fenton process, the focus of this work wastore place th eferrous ions in solution with a solid residue generated in the steel industry, the steel scrap. This is mainly constituted by iron oxides such as wustite, magnetite and hematite, which in combination with hydrogen peroxide trigger a heterogeneous fenton type reaction to produce hydroxyl radicals. As a strategy to reverse effects such as self-aggregation and passivation, thesteel scrap was applied in the form of mixtures with activated carbon in a 7: 3 ratio (coal / steel scrap). The particle size, scale weight and the hydrogen peroxide dose were determined through an experimental design in order to evaluate the Best working conditions to be applied in the treatment of the model compound 2,4-Dinitrophenol (2,4-DNF), using a continuous flow reactor and fixed bed constructed from materials such as PVC and acrylic. The Best conditions resulted in a percentage of degradation of 2,4-DNF greater than 90%, and a reduction in the Chemical Oxygen Demandabove 66%, suggesting partial mineralization with the possibility of formingreaction intermediates with ecotoxicological potential. The characterization of the catalytic material usingthe XRD and SEM-EDS techniques, suggestthepotential for reuse, as no significantchanges in crystallinityandElemental phase composition were identified in samples used in the treatment. Finally, it is concluded that thereis a need for the use of complementary studies aimed at the Chemical and ecotoxicological characterization of the treated efluent associated with anoptimization of the treatment processused.