Óxidos de ferro sintetizados a partir de ferro metálico e suas aplicações em catálise

Abstract

In this paper iron oxides were synthesized through the reaction of iron in hydrochloric acid and oxalic acid (MagA). The materials formed were compared to those synthesized usin iron chloride II as precursor salt (MagS). Some materials were doped with nickel (MagANi e MagSNi). The materials were characterized by XRD, FTIR, SEM, TGA, FRX and Raman Spectroscopy, which indicated the presence of magnetite, maghemite and hematite in the materials. The catalyticcapacitywasevaluatedbyhydrogen peroxide decomposition in presenceofwaterandorganiccompoundsanddiscolorationtestsofmethylene blue (AM) 10 mg L-1andblackremazol (REM) 10 mg L-1throughtheFentonreactionduring 180 min. The adsorptioncapacitywasalsoevaluated. Allmaterialspresented 90% degradabilityof blue methylenecompound, andlowremovalofremazolblackdye. For adsorption, thetestsresulted in approximately 80% removalofmethylene blue in 180 min for theMagSandMagAcatalystsand 55% dyeremoval for metal dopedcatalysts. Mostofthethecatalystspresentedleaching, excepted for MagA, whichis more suitable for application in heterogeneousFentonprocessdueto its lowcostandgoodresults for dyedegradationof AM and REM.