Optimization of the heterogeneous Fenton-oxidation of the model pollutant 2,4-xylidine using the optimal experimental design methodology

Iron cycling during the autocatalytic decomposition of benzoic acid derivatives by Fenton-like and photo-Fenton techniques

“…The flow rate was 1 mL min −1 . Fe(II) concentrations were quantified by a colorimetric technique through the complex formed with o-phenanthroline [23] . LC-MS analyses were performed using a Thermo Finnigan Surveyor MSQ chromatograph, equipped with an interface for electrospray ionization, a quadrupole analyzer and a diode array detector.…”

“…Control experiments were also performed using aqueous solutions of identical Fe(III) concentration, but in the absence of HBAs. The production of Fe(II) at different reaction times was analyzed by adding 1.5 mL of o-phenanthroline as colorimetric reagent and measuring the absorbance values at 510 nm [23].…”

“…The production of Fe(II) was measured by the o-phenanthroline method [23], whereas the production of hydroxyl radicals was quantified from the amount of benzene transformed into phenol (PhOH)). Under these conditions, HBAs oxidation rates were very low (below 2.5% after 35 min of irradiation).…”

Azo-dye orange II degradation by the heterogeneous Fenton-like process using a zeolite Y-Fe catalyst—Kinetics with a model based on the Fermi's equation

“…Zeolites [13][14][15][16][17], carbon materials [18,19], mesoporous and mixed oxides [20,21] and clays [12,[22][23][24][25][26] have been used as sup-ports of iron in the preparation of heterogeneous catalytic systems. In particular, zeolites containing transition metal ions have been shown to be promising solid-phase catalysts in the oxidation of a series of organic pollutants with hydrogen peroxide [27].…”

Aplicação de processo oxidativo avançado (POA) como pré-tratamento de efluente de laticínio para posterior tratamento biológico

“…Ao empregar ferramentas de planejamento de experimentos Enriquez et al (2004) otimizaram um sistema de tratamento para a degradação do 2,4-xilidino através de reação de foto-Fenton solar. Em outros estudos Raj e Quen (2005) empregaram a técnica estatística de Taguchi para análise, avaliação e otimização de um sistema híbrido composto de 1) um módulo baseado em processo oxidativo avançado (UV/H 2 O 2 ) e 2) um segundo módulo baseado em tratamento biológico para a degradação de águas residuárias contendo tetrahidrofurano.…”