Juliana Ferreira De Brito - Academia.edu (original) (raw)

Papers by Juliana Ferreira De Brito

Research paper thumbnail of Direct Z‐scheme among Niobium Pentoxide and Poly(heptazine imide) for NH 3 Photoelectrosynthesis under Ambient Conditions

Research paper thumbnail of Capítulo 11. O emprego da eletroquímica na transformação da biomassa em produtos de alto valor agregado

Research paper thumbnail of Comparison of deposition methods of Pt under photocatalytic activity of Sb2Se3 thin films

XXVII CIC e XII CIDTI, Feb 25, 2021

Research paper thumbnail of The Substrate Morphology Effect for Sulfur-Rich Amorphous Molybdenum Sulfide for Electrochemical Hydrogen Evolution Reaction

Journal of The Electrochemical Society, 2022

Amorphous molybdenum sulfide (MoSx) is a promising material for hydrogen evolution reaction (HER)... more Amorphous molybdenum sulfide (MoSx) is a promising material for hydrogen evolution reaction (HER) due to its nearly zero hydrogen adsorption free energy at the sulfur (S) edge-sites. To prepare more efficient MoSx-based electrocatalysts, new attempts are required to increase the exposure of the MoSx lateral size and, therefore, increase the S atom’s contents. The majority of studies reported in the literature investigate MoSx over conductive substrates. However, MoSx can be electrodeposited over inexpensive and chemically stable platforms, such as semiconductors. This work presents the semiconductor substrate morphology effect for prepared sulfur-rich MoSx for electrochemical hydrogen evolution reaction. The electrodes are prepared by cyclic voltammetry with 25 cycles over TiO2 film and TiO2 nanotubes (TiO2NT) substrates. The MoSx deposit on TiO2NT presents an increase S atoms contents and exhibits excellent HER activity with a low overpotential of 93 ± 7.5 mV to reach −10 mA cm−2 a...

Research paper thumbnail of O emprego da eletroquímica na transformação da biomassa em produtos de alto valor agregado

Biomassa: estrutura, propriedades e aplicações, 2020

Research paper thumbnail of Influence of electrode materials in the photoelectrocatalytic CO2 reduction

Research paper thumbnail of High Faradaic selectivity in the CO 2 electrocatalytic reduction to formate over Cu 2 OCu hybrid nanoparticles on gas-diffusion-layer electrode

CO2 is electrocatalytic reduced using a carbon diffusion layer decorated with copper oxide (I) na... more CO2 is electrocatalytic reduced using a carbon diffusion layer decorated with copper oxide (I) nanoparticles (GDL/Cu2O) electrode. The CO2 reduction was studied during 18 h forming 4.30 mmol·L -1 of formate with 97% of selectivity. Electrode characterization after the CO2 reduction indicates that the initial Cu2O nanoparticles transformed to a hybrid Cu2O-Cu system to which the high Faradaic selectivity is attributed. The cathode was used also in a full PEC cell, using TiO2 nanotube array/CuO as photoanode with the formation of formate, acetate and hydrogen without external bias and sacrificial agents with Faradaic efficiency of 98%.

Research paper thumbnail of Aqueous CO 2 Reduction on Nanotubes TiO 2 Modified by Copper Porphyrins

The photoconversion of CO2 by artificial photosynthesis is an area of great interest [1]. In this... more The photoconversion of CO2 by artificial photosynthesis is an area of great interest [1]. In this context, there is a great search for new semiconductors able to generate charge carriers (e-/h+) when irradiated by sunlight. Thus, the present work investigated the surface modification of TiO2 nanotubes electrodes (NtTiO2) with copper porphyrins for the CO2 reduction by electrocatalysis, photocatalysis, and photoelectrocatalysis using UV/vis light and different potentials during 2h. For this, NtTiO2 were constructed by anodization [2] and modified with three different porphyrins: [Cu(T4H3MPP)] (NtTiO2-P1), [Cu(TDCPP)] (NtTiO2-P2) and [Cu(TDCSPP)] (NtTiO2-P3) (P1 and P2 = neutral copper(II)porphyrins and P3 = anionic Cu(II)porphyrin) using a wet chemical deposition method. These electrodes were characterized by SEM, XRD, linear and cyclic voltammetry. The CO2 reductions were performed in 0.1 mol L-1 Na2SO4 with CO2 using a photoelectrochemical reactor and Xe lamp of 300 W (Newport 6700...

Research paper thumbnail of Reduction of CO 2 by Photoelectrochemical Process Using Non‐Oxide Two‐Dimensional Nanomaterials – A Review

Research paper thumbnail of Photoelectrodes of Cu2O with interfacial structure of topological insulator Bi2Se3 contributes to selective photoelectrocatalytic reduction of CO2 towards methanol

Journal of CO2 Utilization, 2020

Artificial photosynthesis emerges as feasible solution to diminish CO 2 content in the atmosphere... more Artificial photosynthesis emerges as feasible solution to diminish CO 2 content in the atmosphere. Photoelectrocatalysis can diminish CO 2 concentration while generating useful resources such as methanol. Here an alternative multilayer photoelectrode of FTO/Cu/Bi 2 Se 3-Se/Cu 2 O is developed to enhance selective reduction of CO 2 towards methanol. A novel electrosynthetic approach is described as strategy to modulate the atomic composition of p-type bismuth selenide chalcogenide intralayer. This method enhanced performance and selectivity of n-type Cu 2 O photoelectrocatalysts. Alkaline pH conditions favored yield and selectivity towards methanol production from CO 2. The formation of an n-p heterojunction affects the Cu 2 O performance on CO 2 reduction. The novel engineered FTO/Cu/Bi 2 Se 3-Se/Cu 2 O multilayer photoelectrodes allowed obtaining up to 4.5 mM of methanol, which correspond to 3-fold higher concentration than conventional FTO/Cu 2 O electrodes reported in literature. Photoelectrodes of FTO/ Cu/Bi 2 Se 3-Se/Cu 2 O overperform conventional Cu 2 O in terms of kinetics and selectivity towards methanol production.

Research paper thumbnail of Artificial photosynthesis for alcohol and 3-C compound formation using BiVO4-lamelar catalyst

Journal of CO2 Utilization, 2020

The high levels of atmospheric CO 2 transformed this compound in a preoccupant pollutant. However... more The high levels of atmospheric CO 2 transformed this compound in a preoccupant pollutant. However, a wide range of semiconductors, including bismuth vanadate (BiVO 4), can be applied for CO 2 reduction aiming generation of fuels. This work reports the optimization of the BiVO 4 layer synthesis by microwave system using factorial experimental design, where the variables time (5 to 15 min) and temperature (120 to 160°C) were studied. For evaluation purposes, the materials synthetized were applied in photocatalytic reduction of CO 2. All the BiVO 4 materials analyzed promoted the formation of methanol. The best condition was obtained under the material synthesized at 160°C with 15 min of reaction, where 1.5 mmol L −1 g cat −1 of methanol was produced after 120 min of photocatalysis. For the first time, acetone formation was observed in this kind of material. The best condition for acetone production was acquire with the material prepared at 140°C with 10 min of synthesis, where 0.030 mmol L −1 g cat −1 was generated after 240 min of CO 2 reduction. Differences in methanol concentration obtained among the samples were probably related to crystallographic patterns of the material, once the presence of Bi 2 O 3 or other BiVO 4 crystallographic species may affect the efficiency of the material. The results obtained in this work show that the use of BiVO 4 layer semiconductor prepared by microwave system for CO 2 reduction leads to the generation of high amounts of methanol under just UV-vis light incidence, aside from promoting the production of acetone.

Research paper thumbnail of Contribution of thin films of ZrO2 on TiO2 nanotubes electrodes applied in the photoelectrocatalytic CO2 conversion

Journal of CO2 Utilization, 2018

Zirconium dioxide (ZrO 2) nanoparticles deposited on TiO 2 nanotube (NT) surfaces (30 nm of diame... more Zirconium dioxide (ZrO 2) nanoparticles deposited on TiO 2 nanotube (NT) surfaces (30 nm of diameter) improved the photoelectrocatalytic conversion of carbon dioxide to fuel alcohol. The deposition of ZrO 2 nanoparticles was performed by a wet chemical deposition method, which provided excellent interaction with the nanotubular catalyst, as confirmed by surface analysis techniques. Methanol (485 μmol L −1) and ethanol (268 μmol L −1) were the main products generated under optimized condition after 60 min of the photoelectrochemical reduction of dissolved CO 2 in 0.1 mol L −1 Na 2 SO 4 solution (pH 4.0) by Ti/TiO 2 NT-ZrO 2 at −0.3 V vs. Ag/AgCl (3.0 mol L −1 KCl), under irradiation from an Hg lamp (120 mW cm −2). The ZrO 2 deposits on Ti/TiO 2 NT electrode surface amplified the photocurrent around 282% in −0.7 V, compared to Ti/TiO 2 NT, increasing methanol and ethanol formation by 1054 and 2934%, respectively, after 60 min of the photoelectrocatalysis process. These results demonstrated the potential of using composites of Ti/TiO 2 NT-ZrO 2 in photoelectrocatalytic reduction of dissolved CO 2 and contribute to the development of efficient technologies for fuel production and the reduction of pollutants emissions to the environment.

Research paper thumbnail of An Artificial Photosynthesis System Based on Ti/TiO2 Coated with Cu(II) Aspirinate Complex for CO2 Reduction to Methanol

Electrocatalysis, 2017

A novel copper(II) aspirinate complex easily deposited onto nanotubes of Ti/TiO 2 was successfull... more A novel copper(II) aspirinate complex easily deposited onto nanotubes of Ti/TiO 2 was successfully employed in the conversion of CO 2 to methanol through the use of UV-Vis irradiation coupled to a bias potential of −0.35 V vs saturated calomel electrode. An average concentration of 0.8 mmol L −1 of methanol was obtained in 0.1 mol L −1 of sodium sulfate saturated with CO 2 using a self-organized Ti/ TiO 2 nanotubular array electrode coated with a [Cu 2 (asp) 4 ] complex. The influence exerted by CO 2 and the complex over the behavior of photocurrent vs potential curves is discussed. Furthermore, a complete investigation of all parameters that tend to influence the global process of methanol production by the photoelectrocatalytic method such as applied potential, electrolyte, and time is also thoroughly presented.

Research paper thumbnail of Appraisal of photoelectrocatalytic oxidation of glucose and production of high value chemicals on nanotube Ti/TiO2 electrode

Electrochimica Acta, 2016

The present work describes an alternative process for glucose oxidation via photoelectrocatalytic... more The present work describes an alternative process for glucose oxidation via photoelectrocatalytic technique using Ti/TiO 2 nanotubes as photoanodes. Under optimum experimental conditions, which entailed 10.0 mM glucose in 0.1 M Na 2 SO 4 , pH 6.60, E app = 1.5 V and UV irradiation we were able to convert 78% of glucose following 180 min of photoelectrocatalysis. Out of that, only 28% was, in effect, converted to CO 2 as detected by total organic carbon removal. During the course of the process, a large part of this glucose was found to be transformed into products among them including Arabinose, Arabinitol, 4ketoglicose, glucohexodialdose, Glucone-d-Lactone, 6-deoxiglucose and Gluconic Acid, where this detection was aided by ion-exchange chromatography with amperometric detection and gas chromatography-mass spectra. The results thus essentially demonstrate that photoelectrocatalys can be considered a suitable alternative in fostering glucose conversion, in aqueous medium, to high added value products using a relatively simple and economic method.

Research paper thumbnail of Combination of photoelectrocatalysis and ozonation: A novel and powerful approach applied in Acid Yellow 1 mineralization

Applied Catalysis B: Environmental, 2016

Photoelectrocatalytic oxidation (PEC) is known to be a powerful technique employed with the aim o... more Photoelectrocatalytic oxidation (PEC) is known to be a powerful technique employed with the aim of promoting organic degradation. Its efficiency is nonetheless found to be dramatically decreased when applied in highly concentrated effluent treatment owing to the reduced transparency which minimizes the photons reaching the semiconductor surface. In light of that, the present work seeks to describe a novel combination of photoelectrocatalysis and ozonation (O 3 + PEC) techniques, aiming at achieving a faster decolorization of a highly concentrated solution and a higher rate of mineralization. The Acid Yellow 1 dye (AY1), widely used in cosmetics was chosen as a colorful solution model. TiO 2 nanotubes electrode was used as photoanode in an annular bubble reactor operating at 2.0 V with UV-B irradiation in the presence of 1.25 × 10 −4 mol min −1 of O 3. The main factors interfering in the O 3 + PEC process were optimized through UV/vis spectrophotometry, total organic carbon (TOC) and mass spectrometry measurements. After 20 min of treatment using the combined system, 100% of decolorization was observed while a total mineralization was seen following 60 min of treatment even in effluents containing 100 ppm AY1. Concomitantly, the combined system (O 3 + PEC) showed higher decolorization rate constant and lower energy consumption compared to the other techniques, showing that O 3 + PEC is a successful, efficient and cost-effective alternative for water treatment.

Research paper thumbnail of Adsorption of Aromatic Compounds Under Magnetic Field Influence

Water, Air, & Soil Pollution, 2012

The contamination of water by domestic, industrial, and agribusiness waste is a worldwide concern... more The contamination of water by domestic, industrial, and agribusiness waste is a worldwide concern. There are several ways to treat this type of contamination; one of which is adsorption. The goal of this paper was to evaluate the efficiency of adsorption with activated carbon under the influence of a magnetic field. To this end, we have used the Adsorption Inductor Device with magnetic fields Batista et al. (Dispositivo Indutor de Adsorção. PI0705597-8, 2007). The adsorptive tests at both presence (P) and absence (A) of the magnetic field were performed using different substances: methylene blue and phenol, and analyzed by several experimental techniques.

Research paper thumbnail of Tratamento da água de purificação do biodiesel utilizando eletrofloculação

Química Nova, 2012

Recebido em 30/5/11; aceito em 9/10/11; publicado na web em 20/1/12 TREATMENT FOR PURIFICATION WA... more Recebido em 30/5/11; aceito em 9/10/11; publicado na web em 20/1/12 TREATMENT FOR PURIFICATION WATER OF BIODIESEL USING ELECTROFLOCULATION. Biodiesel was created as a solution for a great economic and enviromental problem of petroleum, a resource with sustainable characteristics. But its production still needs optimization, because it uses a lot of water and generates a large volume of this residue, which appears improper to disposal without correct treatment. This work propose an economic, viable and efficient way to treat the Biodiesel purification water, not only aiming at a proper disposal, but the reuse as input in the process, generating a large industrial economy, and greater environmental progress. For both treatment uses the electrofloculation technique.

Research paper thumbnail of Direct Z‐scheme among Niobium Pentoxide and Poly(heptazine imide) for NH 3 Photoelectrosynthesis under Ambient Conditions

Research paper thumbnail of Capítulo 11. O emprego da eletroquímica na transformação da biomassa em produtos de alto valor agregado

Research paper thumbnail of Comparison of deposition methods of Pt under photocatalytic activity of Sb2Se3 thin films

XXVII CIC e XII CIDTI, Feb 25, 2021

Research paper thumbnail of The Substrate Morphology Effect for Sulfur-Rich Amorphous Molybdenum Sulfide for Electrochemical Hydrogen Evolution Reaction

Journal of The Electrochemical Society, 2022

Amorphous molybdenum sulfide (MoSx) is a promising material for hydrogen evolution reaction (HER)... more Amorphous molybdenum sulfide (MoSx) is a promising material for hydrogen evolution reaction (HER) due to its nearly zero hydrogen adsorption free energy at the sulfur (S) edge-sites. To prepare more efficient MoSx-based electrocatalysts, new attempts are required to increase the exposure of the MoSx lateral size and, therefore, increase the S atom’s contents. The majority of studies reported in the literature investigate MoSx over conductive substrates. However, MoSx can be electrodeposited over inexpensive and chemically stable platforms, such as semiconductors. This work presents the semiconductor substrate morphology effect for prepared sulfur-rich MoSx for electrochemical hydrogen evolution reaction. The electrodes are prepared by cyclic voltammetry with 25 cycles over TiO2 film and TiO2 nanotubes (TiO2NT) substrates. The MoSx deposit on TiO2NT presents an increase S atoms contents and exhibits excellent HER activity with a low overpotential of 93 ± 7.5 mV to reach −10 mA cm−2 a...

Research paper thumbnail of O emprego da eletroquímica na transformação da biomassa em produtos de alto valor agregado

Biomassa: estrutura, propriedades e aplicações, 2020

Research paper thumbnail of Influence of electrode materials in the photoelectrocatalytic CO2 reduction

Research paper thumbnail of High Faradaic selectivity in the CO 2 electrocatalytic reduction to formate over Cu 2 OCu hybrid nanoparticles on gas-diffusion-layer electrode

CO2 is electrocatalytic reduced using a carbon diffusion layer decorated with copper oxide (I) na... more CO2 is electrocatalytic reduced using a carbon diffusion layer decorated with copper oxide (I) nanoparticles (GDL/Cu2O) electrode. The CO2 reduction was studied during 18 h forming 4.30 mmol·L -1 of formate with 97% of selectivity. Electrode characterization after the CO2 reduction indicates that the initial Cu2O nanoparticles transformed to a hybrid Cu2O-Cu system to which the high Faradaic selectivity is attributed. The cathode was used also in a full PEC cell, using TiO2 nanotube array/CuO as photoanode with the formation of formate, acetate and hydrogen without external bias and sacrificial agents with Faradaic efficiency of 98%.

Research paper thumbnail of Aqueous CO 2 Reduction on Nanotubes TiO 2 Modified by Copper Porphyrins

The photoconversion of CO2 by artificial photosynthesis is an area of great interest [1]. In this... more The photoconversion of CO2 by artificial photosynthesis is an area of great interest [1]. In this context, there is a great search for new semiconductors able to generate charge carriers (e-/h+) when irradiated by sunlight. Thus, the present work investigated the surface modification of TiO2 nanotubes electrodes (NtTiO2) with copper porphyrins for the CO2 reduction by electrocatalysis, photocatalysis, and photoelectrocatalysis using UV/vis light and different potentials during 2h. For this, NtTiO2 were constructed by anodization [2] and modified with three different porphyrins: [Cu(T4H3MPP)] (NtTiO2-P1), [Cu(TDCPP)] (NtTiO2-P2) and [Cu(TDCSPP)] (NtTiO2-P3) (P1 and P2 = neutral copper(II)porphyrins and P3 = anionic Cu(II)porphyrin) using a wet chemical deposition method. These electrodes were characterized by SEM, XRD, linear and cyclic voltammetry. The CO2 reductions were performed in 0.1 mol L-1 Na2SO4 with CO2 using a photoelectrochemical reactor and Xe lamp of 300 W (Newport 6700...

Research paper thumbnail of Reduction of CO 2 by Photoelectrochemical Process Using Non‐Oxide Two‐Dimensional Nanomaterials – A Review

Research paper thumbnail of Photoelectrodes of Cu2O with interfacial structure of topological insulator Bi2Se3 contributes to selective photoelectrocatalytic reduction of CO2 towards methanol

Journal of CO2 Utilization, 2020

Artificial photosynthesis emerges as feasible solution to diminish CO 2 content in the atmosphere... more Artificial photosynthesis emerges as feasible solution to diminish CO 2 content in the atmosphere. Photoelectrocatalysis can diminish CO 2 concentration while generating useful resources such as methanol. Here an alternative multilayer photoelectrode of FTO/Cu/Bi 2 Se 3-Se/Cu 2 O is developed to enhance selective reduction of CO 2 towards methanol. A novel electrosynthetic approach is described as strategy to modulate the atomic composition of p-type bismuth selenide chalcogenide intralayer. This method enhanced performance and selectivity of n-type Cu 2 O photoelectrocatalysts. Alkaline pH conditions favored yield and selectivity towards methanol production from CO 2. The formation of an n-p heterojunction affects the Cu 2 O performance on CO 2 reduction. The novel engineered FTO/Cu/Bi 2 Se 3-Se/Cu 2 O multilayer photoelectrodes allowed obtaining up to 4.5 mM of methanol, which correspond to 3-fold higher concentration than conventional FTO/Cu 2 O electrodes reported in literature. Photoelectrodes of FTO/ Cu/Bi 2 Se 3-Se/Cu 2 O overperform conventional Cu 2 O in terms of kinetics and selectivity towards methanol production.

Research paper thumbnail of Artificial photosynthesis for alcohol and 3-C compound formation using BiVO4-lamelar catalyst

Journal of CO2 Utilization, 2020

The high levels of atmospheric CO 2 transformed this compound in a preoccupant pollutant. However... more The high levels of atmospheric CO 2 transformed this compound in a preoccupant pollutant. However, a wide range of semiconductors, including bismuth vanadate (BiVO 4), can be applied for CO 2 reduction aiming generation of fuels. This work reports the optimization of the BiVO 4 layer synthesis by microwave system using factorial experimental design, where the variables time (5 to 15 min) and temperature (120 to 160°C) were studied. For evaluation purposes, the materials synthetized were applied in photocatalytic reduction of CO 2. All the BiVO 4 materials analyzed promoted the formation of methanol. The best condition was obtained under the material synthesized at 160°C with 15 min of reaction, where 1.5 mmol L −1 g cat −1 of methanol was produced after 120 min of photocatalysis. For the first time, acetone formation was observed in this kind of material. The best condition for acetone production was acquire with the material prepared at 140°C with 10 min of synthesis, where 0.030 mmol L −1 g cat −1 was generated after 240 min of CO 2 reduction. Differences in methanol concentration obtained among the samples were probably related to crystallographic patterns of the material, once the presence of Bi 2 O 3 or other BiVO 4 crystallographic species may affect the efficiency of the material. The results obtained in this work show that the use of BiVO 4 layer semiconductor prepared by microwave system for CO 2 reduction leads to the generation of high amounts of methanol under just UV-vis light incidence, aside from promoting the production of acetone.

Research paper thumbnail of Contribution of thin films of ZrO2 on TiO2 nanotubes electrodes applied in the photoelectrocatalytic CO2 conversion

Journal of CO2 Utilization, 2018

Zirconium dioxide (ZrO 2) nanoparticles deposited on TiO 2 nanotube (NT) surfaces (30 nm of diame... more Zirconium dioxide (ZrO 2) nanoparticles deposited on TiO 2 nanotube (NT) surfaces (30 nm of diameter) improved the photoelectrocatalytic conversion of carbon dioxide to fuel alcohol. The deposition of ZrO 2 nanoparticles was performed by a wet chemical deposition method, which provided excellent interaction with the nanotubular catalyst, as confirmed by surface analysis techniques. Methanol (485 μmol L −1) and ethanol (268 μmol L −1) were the main products generated under optimized condition after 60 min of the photoelectrochemical reduction of dissolved CO 2 in 0.1 mol L −1 Na 2 SO 4 solution (pH 4.0) by Ti/TiO 2 NT-ZrO 2 at −0.3 V vs. Ag/AgCl (3.0 mol L −1 KCl), under irradiation from an Hg lamp (120 mW cm −2). The ZrO 2 deposits on Ti/TiO 2 NT electrode surface amplified the photocurrent around 282% in −0.7 V, compared to Ti/TiO 2 NT, increasing methanol and ethanol formation by 1054 and 2934%, respectively, after 60 min of the photoelectrocatalysis process. These results demonstrated the potential of using composites of Ti/TiO 2 NT-ZrO 2 in photoelectrocatalytic reduction of dissolved CO 2 and contribute to the development of efficient technologies for fuel production and the reduction of pollutants emissions to the environment.

Research paper thumbnail of An Artificial Photosynthesis System Based on Ti/TiO2 Coated with Cu(II) Aspirinate Complex for CO2 Reduction to Methanol

Electrocatalysis, 2017

A novel copper(II) aspirinate complex easily deposited onto nanotubes of Ti/TiO 2 was successfull... more A novel copper(II) aspirinate complex easily deposited onto nanotubes of Ti/TiO 2 was successfully employed in the conversion of CO 2 to methanol through the use of UV-Vis irradiation coupled to a bias potential of −0.35 V vs saturated calomel electrode. An average concentration of 0.8 mmol L −1 of methanol was obtained in 0.1 mol L −1 of sodium sulfate saturated with CO 2 using a self-organized Ti/ TiO 2 nanotubular array electrode coated with a [Cu 2 (asp) 4 ] complex. The influence exerted by CO 2 and the complex over the behavior of photocurrent vs potential curves is discussed. Furthermore, a complete investigation of all parameters that tend to influence the global process of methanol production by the photoelectrocatalytic method such as applied potential, electrolyte, and time is also thoroughly presented.

Research paper thumbnail of Appraisal of photoelectrocatalytic oxidation of glucose and production of high value chemicals on nanotube Ti/TiO2 electrode

Electrochimica Acta, 2016

The present work describes an alternative process for glucose oxidation via photoelectrocatalytic... more The present work describes an alternative process for glucose oxidation via photoelectrocatalytic technique using Ti/TiO 2 nanotubes as photoanodes. Under optimum experimental conditions, which entailed 10.0 mM glucose in 0.1 M Na 2 SO 4 , pH 6.60, E app = 1.5 V and UV irradiation we were able to convert 78% of glucose following 180 min of photoelectrocatalysis. Out of that, only 28% was, in effect, converted to CO 2 as detected by total organic carbon removal. During the course of the process, a large part of this glucose was found to be transformed into products among them including Arabinose, Arabinitol, 4ketoglicose, glucohexodialdose, Glucone-d-Lactone, 6-deoxiglucose and Gluconic Acid, where this detection was aided by ion-exchange chromatography with amperometric detection and gas chromatography-mass spectra. The results thus essentially demonstrate that photoelectrocatalys can be considered a suitable alternative in fostering glucose conversion, in aqueous medium, to high added value products using a relatively simple and economic method.

Research paper thumbnail of Combination of photoelectrocatalysis and ozonation: A novel and powerful approach applied in Acid Yellow 1 mineralization

Applied Catalysis B: Environmental, 2016

Photoelectrocatalytic oxidation (PEC) is known to be a powerful technique employed with the aim o... more Photoelectrocatalytic oxidation (PEC) is known to be a powerful technique employed with the aim of promoting organic degradation. Its efficiency is nonetheless found to be dramatically decreased when applied in highly concentrated effluent treatment owing to the reduced transparency which minimizes the photons reaching the semiconductor surface. In light of that, the present work seeks to describe a novel combination of photoelectrocatalysis and ozonation (O 3 + PEC) techniques, aiming at achieving a faster decolorization of a highly concentrated solution and a higher rate of mineralization. The Acid Yellow 1 dye (AY1), widely used in cosmetics was chosen as a colorful solution model. TiO 2 nanotubes electrode was used as photoanode in an annular bubble reactor operating at 2.0 V with UV-B irradiation in the presence of 1.25 × 10 −4 mol min −1 of O 3. The main factors interfering in the O 3 + PEC process were optimized through UV/vis spectrophotometry, total organic carbon (TOC) and mass spectrometry measurements. After 20 min of treatment using the combined system, 100% of decolorization was observed while a total mineralization was seen following 60 min of treatment even in effluents containing 100 ppm AY1. Concomitantly, the combined system (O 3 + PEC) showed higher decolorization rate constant and lower energy consumption compared to the other techniques, showing that O 3 + PEC is a successful, efficient and cost-effective alternative for water treatment.

Research paper thumbnail of Adsorption of Aromatic Compounds Under Magnetic Field Influence

Water, Air, & Soil Pollution, 2012

The contamination of water by domestic, industrial, and agribusiness waste is a worldwide concern... more The contamination of water by domestic, industrial, and agribusiness waste is a worldwide concern. There are several ways to treat this type of contamination; one of which is adsorption. The goal of this paper was to evaluate the efficiency of adsorption with activated carbon under the influence of a magnetic field. To this end, we have used the Adsorption Inductor Device with magnetic fields Batista et al. (Dispositivo Indutor de Adsorção. PI0705597-8, 2007). The adsorptive tests at both presence (P) and absence (A) of the magnetic field were performed using different substances: methylene blue and phenol, and analyzed by several experimental techniques.

Research paper thumbnail of Tratamento da água de purificação do biodiesel utilizando eletrofloculação

Química Nova, 2012

Recebido em 30/5/11; aceito em 9/10/11; publicado na web em 20/1/12 TREATMENT FOR PURIFICATION WA... more Recebido em 30/5/11; aceito em 9/10/11; publicado na web em 20/1/12 TREATMENT FOR PURIFICATION WATER OF BIODIESEL USING ELECTROFLOCULATION. Biodiesel was created as a solution for a great economic and enviromental problem of petroleum, a resource with sustainable characteristics. But its production still needs optimization, because it uses a lot of water and generates a large volume of this residue, which appears improper to disposal without correct treatment. This work propose an economic, viable and efficient way to treat the Biodiesel purification water, not only aiming at a proper disposal, but the reuse as input in the process, generating a large industrial economy, and greater environmental progress. For both treatment uses the electrofloculation technique.