Iron-doped catalyst synthesis in heterogeneous Fenton like process for dye degradation and removal: optimization using response surface methodology (original) (raw)
Related papers
Applied Catalysis B-environmental, 2011
This work deals with the elimination of the azo-dye Orange II (OII) by the heterogeneous Fenton's process. Three different commercial activated carbons (ACs), Norit RX 3 Extra, Merck and Kynol, were used as Fe-supports to develop Fenton catalysts (7 wt.% Fe/C). Both supports and catalysts were characterized by several techniques (N 2 and CO 2 adsorption, XRD, TEM). The elimination of the dye is a complex heterogeneous process with co-existence of adsorption and oxidation. Adsorption and catalytic experiments were carried out with only 0.1 g L −1 of solid in a slurry batch reactor at 30 • C, pH 3 and initial dye concentration of 0.1 mM. The decolorization was followed continuously by the absorbance measurement; mineralization and leaching levels were evaluated by TOC and atomic absorption analyses, respectively. Correlations of ACs characteristics with their adsorptive or catalytic performances were established, in order to select the best support. All the ACs are microporous materials and the OII adsorption is favoured by an increase of the micropore width. Although the carbon surface proves to be catalytically active, the main OII elimination process in pure ACs is adsorption, while for the Fe-catalyst it is determined by the Fenton oxidation. The Fe-Norit is the most active catalyst, which is associated to its high surface area located on large micropores that favours both the OII adsorption and the Fe-dispersion. However, this catalyst presented the highest tendency to the leaching. Anyway, the leaching values remain quite low even in this case (<1.7% of the total Fe), guarantying the possible reuse of the catalysts.
Azo-dye Orange II degradation by heterogeneous Fenton-like reaction using carbon-Fe catalysts
Applied Catalysis B: Environmental, 2007
In this work, the degradation and mineralization of the non-biodegradable azo dye Orange II (OII) was studied, making use of a heterogeneous Fenton-like oxidation process. For that, hydrogen peroxide activation was achieved by means of two different carbon-based catalysts, which have been impregnated with 7 wt% of iron. The carbon supports employed are quite different, one of them being an activated carbon prepared from agricultural by-products (olive stone), while the other one is a carbon aerogel, prepared by carbonization of an organic resorcinol-formaldehyde polymer. The solids have been characterized using several techniques, namely N 2 and CO 2 adsorption at À196 and 0 8C, respectively, mercury porosimetry, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), x-ray diffraction (XRD) and xray photoelectron spectroscopy (XPS). Then, the catalyst's performance in the Fenton-like oxidation of OII was compared, and the effects of the most relevant operating conditions (pH, catalyst concentration, H 2 O 2 concentration and temperature) analyzed for the most promising one (the carbon aerogel based catalyst). In this catalyst, characterization data point for a very good iron dispersion on the carbon surface. This sample showed very good catalytic performances, with mineralization degrees as high as 90%. However, iron leaching from the support is also considerable leading to a progressive deactivation in consecutive reaction cycles. #
Degradation of Orange G by Fenton-like reaction with Fe-impregnated biochar catalyst
Bioresource technology, 2017
This study was conducted to evaluate the catalytic activity of Fe-impregnated sugarcane biochar (FSB) for removing azo dye Orange G (OG) from solution under various Fenton-like oxidation conditions. The optimum molar Fe concentration for impregnation to achieve maximum catalytic activity of FSB in Fenton-like reaction with acceptable effluent Fe release was 0.25 M (163.4 Fe mg/g in FSB). High removal efficiency of 99.7% was achieved within 2 h of reaction at optimum conditions of 0.075 g/L H2O2, 0.5 g/L FSB for 0.1 g/L OG at initial pH 5.5 under 25 °C. For every 10 °C increase, the time for maximum OG degradation efficiency decreased by 0.5 h. The OG removal by FSB exhibited a slow induction reaction followed by fast OG decomposition. FSB can be used successively for at least 4 runs with >89.3% OG removal. The FSB was more economical, efficient, and recyclable than other conventional Fenton oxidation catalysts.
In-house-prepared carbon-based Fe-doped catalysts for electro-Fenton degradation of azo dyes
Journal of the Serbian Chemical Society, 2022
Compounds used in the fashion industry effect the water bodies in the vicinity of textile factories, resulting in the visible coloration of surface water. Fe-doped graphite-based in house prepared electrodes were used in the Fenton-like degradation of Reactive Blue 52 (RB52). The electrodes consisting of high-density graphite in three granulation sizes and three levels of Fe content were characterized using scanning electron microscopy (SEM). The amount of Fe in the electrodes and H 2 O 2 concentration in synthetic textile wastewater were optimized. Additionally, the size of graphite grains was varied to investigate whether it effects the degradation rate. Under only 10 min of electro-Fenton degradation, a system with 10 mmol dm-3 of H 2 O 2 and an electrode made of 7 % of Fe and 70 µm of granulation size of graphite, degraded over 75 % of RB52, and over 99 % after 40 min of treatment. The obtained results indicate that the proposed approach could be beneficial in the field of novel materials for environmental application and that in house prepared carbon could be an excellent replacement for commercially available supports.
Acta Chimica Slovenica
Oxidative treatment of a cationic dye solution, methylene blue, was investigated using magnetite nanoparticles and goethite in heterogeneous Fenton-like reaction, and ferrous ions in homogeneous Fenton-reaction. The aim was to compare the degradation efficiencies of the studied catalysts for decolorization of methylene blue solution as the model organic pollutant. Response surface methodology (RSM) was applied to determine the optimal operational conditions for magnetite/H 2 O 2 and goethite/H 2 O 2 systems. The [H 2 O 2 ] of 0.2 M, catalyst dosage of 1 g/L, pH 9.0 and reaction time of 5h were chosen by RSM. The pH value of 3.0 was used in the case of Fe +2 /H 2 O 2 system. The experimental results showed that homogeneous Fenton oxidation system was the most effective system under both acidic and neutral conditions but decreased at pH value of 9.0 due to the decrease in available Fe 2+ ions in the solution and generation of ferric hydroxide sludge. Fe 3 O 4 /H 2 O 2 system represented better removal efficiency than FeO(OH)/H 2 O 2 system that could be attributed to the presence of Fe II cations in magnetite structure and its larger surface area.
Volume 5 - 2020, Issue 8 - August
Photo-fenton oxidation technique is one of the emerging oxidation processes explored in treatment of organic pollutants in aqueous solutions. This research is focused on utilization of Fe(II) loaded activated carbon and H2O2(aq) in a photofenton process to generate hydroxyl radicals that mineralize methyl orange dyes. Samples of activated carbon were treated with Fe(NO3)2(aq) and characterized using SEM, pHZPC, specific surface area and boehm’s titration. The degradation of methyl orange by the iron loaded activated carbon (Fe-Ac), via photo-Fenton process, was investigated in lab-scale defined by experimental design. Central composite design (CCD) was used to evaluate the effects of the five independent variables considered for the optimization of the oxidative process: time, FeAc dose, methyl orange concentration, pH and H2O2 concentrations. In the optimization, the correlation coefficients (R2 ) for the quadratic model was 0.9941. Optimum reaction conditions were obtained at pH =...
Jurnal Bahan Alam Terbarukan
Methylene blue is one of the dyes in textile industries which has a negative impact on the environment. This compound is very stable, so it is difficult to degrade naturally. Methylene blue can be harmful to the environment if it is in a very large concentration, because it can increase the value of Chemical Oxygen Demand (COD) which can damage the balance of environment ecosystem. Adsorption method by using activated carbon as the adsorbent is one of the most efficient and effective techniques in dye removal due to its large adsorption capacity. However, the adsorption method using activated carbon only removes the pollutant compounds to other media or phases. Other method that can be used includes Advanced Oxidation Processes (AOPs). This method has the advantage of being able to degrade harmful compounds in the waste through oxidation (oxidative degradation) processes. One method of AOPs is the process by using Fenton reagents. This study was aimed to prepare and characterize iro...
Science and Technology Development Journal, 2020
Introduction: Heterogeneous Fenton is one of the Advanced Oxidation Processes (AOPs) and has been proven to be effective on azo dye degradation. However, a low-cost catalyst and factors affecting the processes of this system were further investigated. Methods: In this study, pellets of iron alumina pillared bentonite (PFeAPB) were prepared by dispersing iron ions on alumina pillared bentonite pellet. Catalyst activity and lifetime were investigated via efficiencies of Methyl Orange (MO) decolorization and Chemical Oxygen Demand (COD) removal, a typical dye type of textile wastewater. Characteristics of the PFeAPB catalyst were examined by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, and X-ray fluorescence (XRF). Results: Results of batch experiments showed that specific surface area of the PFeAPB catalyst was 111.22 m2/g higher than its precursor by 2 times (57.79 m2/g). Goethite, Hematite and Maghemite phases with approximately 11.5% of iron elements containi...
Optimization of oxidative MO’s degradation in heterogeneous Fenton-like reaction using Fe-MKSF
Materials Today: Proceedings, 2018
This study investigates the optimal operational conditions for oxidative degradation of methyl orange (MO) in heterogeneous Fenton-like reaction using iron-immobilized montmorillonite KSF (Fe-MKSF) composites. Central composite design (CCD) experiments were used to determine the effects of four operational variables; pH solution, catalyst dosage, concentration of H 2 O 2 and initial concentration of methyl orange dye (MO) on the percentage of MO removal. Based on the analysis of variance (ANOVA), the model illustrated high correlation coefficient (R2) of 0.9589 which demonstrated approximately 96% of target function variation. The optimal operational conditions were found to be at 2.8 pH solution, 0.8g/L catalyst dosage, 15 mM H 2 O 2 concentration and 25 mg/L MO initial concentration which subsequently resulted in 98% of MO removal. Moreover, the experimental values obtained were in good agreement with the values predicted from the model, with relatively slight differences of 1.24%. Such findings shown significant interaction between four operational variables towards MO removal during the heterogeneous Fenton-like reaction using Fe-MKSF composites.