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Schadeck Netto M, Leindcker Rossatto D, Jahn SL, Stoffels Mallmann E, Luiz Dotto G, Luiz Foletto E. Preparation of a novel magnetic geopolymer/zero–valent iron composite with remarkable adsorption performance towards aqueous Acid Red 97. CHEM ENG COMMUN 2019. [DOI: 10.1080/00986445.2019.1635467] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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Silvestri S, Stefanello N, da Silveira Salla J, Foletto EL. Photocatalytic properties of Zn2SnO4 powders prepared by different modified hydrothermal routes. RESEARCH ON CHEMICAL INTERMEDIATES 2019. [DOI: 10.1007/s11164-019-03832-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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May MM, Marchionatti AME, Valandro LF, Foletto EL, Dorneles LS, May LG. Y-TZP surface treatments and their effects on the bond strength to resin cement. BRAZILIAN JOURNAL OF ORAL SCIENCES 2019. [DOI: 10.20396/bjos.v18i0.8655141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Aim: This study evaluated the effect of surface treatments of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramics on their bond strength to a resin cement. Methods: Seventy zirconia blocks (6 × 6 × 2 mm3, IPS e.max ZirCAD) were assigned into 7 groups (n=10) – as-sintered (AS), no treatment; tribochemical silica coating + silanization (TBS; Cojet-sand; ProSil); airabrasion with 45 μm alumina particles + universal primer (AAP; Monobond®Plus); fusion sputtering (FS); SiO2 nanofilm + silanization (SN; ProSil); FS+SN+ silanization (FSSN; ProSil); FS+SN+Universal Primer (FSSNP; Monobond®Plus). Afterwards, a resin cement (RelyX™ ARC) was applied inside cylinders (Ø = 0.96 mm × 1 mm height) placed on the zirconia surfaces. Microshear bond strength tests (μSBS) were carried out (1 mm/min). Failure and phase transformation analysis were performed. Bond strength data (MPa) were subjected to Kruskal-Wallis/Mann Whitney tests. Results: TBS (27 ± 1.2) and AAP (24.7 ± 0.8) showed higher bond strengths than the other groups, followed by FSSNP (15.5 ± 4.2) and FSSN (13.3 ± 3.6). FS (3.4 ± 0.44) and SN (9.5 ± 2.7) showed the lowest values (p < 0.001). Most of the specimens exhibited an adhesive failure. Conclusion: Air-abrasion by silica-coated alumina particles followed by silanization or by alumina particles followed by universal primer resulted in the highest resin bond strength to zirconia. Fusion sputtering and silica nanofilm deposition induced low strengths. However, when these methods are applied in combination and with a primer (FSSN and FSSNP), higher bond strengths may be achieved. Low bond strengths are obtained when no zirconia treatment is performed.
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da Cruz Severo E, Dotto GL, Martínez-de la Cruz A, Cuellar EL, Foletto EL. Enhanced photocatalytic activity of BiVO 4 powders synthesized in presence of EDTA for the decolorization of rhodamine B from aqueous solution. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:34123-34130. [PMID: 30284166 DOI: 10.1007/s11356-018-3370-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 09/27/2018] [Indexed: 05/27/2023]
Abstract
Bismuth vanadate (BiVO4) powders were successfully synthesized in presence of EDTA via microwave irradiation and used as photocatalysts in the oxidation reaction of rhodamine B (rhB) under visible light. Different concentrations of EDTA (0.5 to 10%) to chelate Bi3+ ions were employed on the BiVO4 synthesis. Under the presence of EDTA, a monoclinic crystalline structure was obtained, whereas a mixture of monoclinic and tetragonal phases was observed in the absence of EDTA. In addition, the use of different EDTA concentrations promoted the formation the different shapes of particles. The BiVO4 sample synthesized with low concentration of EDTA (0.5%) exhibited about 85% of rhB decolorization in 300 min at pH 7.5. Therefore, this high efficiency can be attributed to a combination of intrinsic properties such as the morphology type and monoclinic structure of BiVO4 particles.
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Fröhlich AC, Dos Reis GS, Pavan FA, Lima ÉC, Foletto EL, Dotto GL. Improvement of activated carbon characteristics by sonication and its application for pharmaceutical contaminant adsorption. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:24713-24725. [PMID: 29923049 DOI: 10.1007/s11356-018-2525-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 06/10/2018] [Indexed: 06/08/2023]
Abstract
Sonicated activated carbon (SAC) was developed and used to remove ibuprofen and ketoprofen from aqueous media by adsorption. A standard activated carbon sample (AC) was used as comparison. Both adsorbents were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), N2 adsorption isotherms (Brunauer, Emmett, and Teller (BET)), helium gas pycnometry, and scanning electron microscopy (SEM). In the adsorption study, kinetics, equilibrium, and thermodynamics were evaluated. SAC presented better characteristics than AC. Pseudo-second-order model was adequate to predict the kinetic curves. The isotherm data obeyed the Sips model. Thermodynamic results revealed a spontaneous and endothermic process, where physisorption was involved. The maximum adsorption capacities of SAC were 134.5 and 89.2 mg g-1 for ibuprofen and ketoprofen, respectively. For AC, the maximum adsorption capacities were 115.1 and 79.1 mg g-1 for ibuprofen and ketoprofen, respectively. The sonication technique presented great potential to improve the AC characteristics, generating a promising material (SAC) for ibuprofen and ketoprofen adsorption.
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Mota ALN, Neto LGL, Foletto EL, Chiavone-Filho O, Nascimento CAOD. Analysis of solar and artificial UVA irradiations on the photo-Fenton treatment of phenolic effluent and oilfield produced water. CHEM ENG COMMUN 2018. [DOI: 10.1080/00986445.2018.1463524] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Georgin J, da Silva Marques B, da Silveira Salla J, Foletto EL, Allasia D, Dotto GL. Removal of Procion Red dye from colored effluents using H 2SO 4-/HNO 3-treated avocado shells (Persea americana) as adsorbent. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:6429-6442. [PMID: 29249030 DOI: 10.1007/s11356-017-0975-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 12/06/2017] [Indexed: 05/10/2023]
Abstract
The treatment of colored effluents containing Procion Red dye (PR) was investigated using H2SO4 and HNO3 modified avocado shells (Persea americana) as adsorbents. The adsorbent materials (AS-H2SO4 and AS-HNO3) were properly characterized. The adsorption study was carried out considering the effects of adsorbent dosage and pH. Kinetic, equilibrium, and thermodynamic aspects were also evaluated. Finally, the adsorbents were tested to treat simulated dye house effluents. For both materials, the adsorption was favored using 0.300 g L-1 of adsorbent at pH 6.5, where, more than 90% of PR was removed from the solution. General order model was able to explain the adsorption kinetics for both adsorbents. The Sips model was adequate to represent the isotherm data, being the maximum adsorption capacities of 167.0 and 212.6 mg g-1 for AS-H2SO4 and AS-HNO3, respectively. The adsorption processes were thermodynamically spontaneous, favorable (- 17.0 < ΔG 0 < - 13.2 kJ mol-1), and exothermic (ΔH 0 values of - 29 and - 55 kJ mol-1). AS-H2SO4 and AS-HNO3 were adequate to treat dye house effluents, attaining color removal percentages of 82 and 75%. Avocado shells, after a simple acid treatment, can be a low-cost option to treat colored effluents.
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Drumm FC, de Oliveira JS, Foletto EL, Dotto GL, Moraes Flores EM, Peters Enders MS, Müller EI, Janh SL. Response surface methodology approach for the optimization of tartrazine removal by heterogeneous photo-Fenton process using mesostructured Fe2O3-suppoted ZSM-5 prepared by chitin-templating. CHEM ENG COMMUN 2018. [DOI: 10.1080/00986445.2017.1402009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Wandscher VF, Fraga S, Pozzobon JL, Soares FZM, Foletto EL, May LG, Valandro LF. Tribochemical Glass Ceramic Coating as a New Approach for Resin Adhesion to Zirconia. THE JOURNAL OF ADHESIVE DENTISTRY 2017; 18:435-440. [PMID: 27669635 DOI: 10.3290/j.jad.a36892] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
PURPOSE To investigate the effects of a novel tribochemical silica coating technique with powders made from feldspathic ceramic and leucite-based ceramic on the bond strength of zirconia to resin cement before and after aging. MATERIALS AND METHODS Zirconia blocks were divided into 3 groups according to the material used for airborne-particle abrasion: 1) SP (control): silica-coated alumina particles; 2) FP: feldspathic ceramic powder; 3) LP: leucite glass-ceramic powder. After silanization, composite resin cylinders were cemented on the zirconia surface using a dual-curing resin cement. Prior to the shear bond strength (SBS) test, half of the samples (n = 15) were stored in distilled water for 24 h; the other half (n = 15) were submitted to aging (10,000 thermocycles of 5°C to 55°C; 150 days of water storage). The bond strength data were analyzed using two-way ANOVA and Tukey's test (α = 0.05). Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and x-ray diffraction analysis were performed. RESULTS The initial bond strengths did not differ significantly between the groups (p = 0.053). However, after aging procedures, airborne-particle abrasion with feldspathic ceramic powder (FP) resulted in higher values of bond strength (p = 0.0001). SEM and EDS indicated that all the treatments promoted silica deposition on the Y-TZP surface ceramic. Airborne-particle abrasion with FP and LP induced a lower percentage of the monoclinic phase. CONCLUSION Airborne abrasion with fine feldspathic ceramic particles is a novel tribochemical technique and appears to be suitable for improving the bond strength between zirconia and resin cements.
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Foletto VS, Ferreira AB, da Cruz Severo E, Collazzo GC, Foletto EL, Dotto GL. Iron-based adsorbent prepared from Litchi peel biomass via pyrolysis process for the removal of pharmaceutical pollutant from synthetic aqueous solution. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:10547-10556. [PMID: 28281077 DOI: 10.1007/s11356-017-8745-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 03/01/2017] [Indexed: 06/06/2023]
Abstract
A porous iron-based adsorbent obtained from litchi peel via pyrolysis process was prepared in this work, in order to evaluate its adsorptive potential for the removal of a pharmaceutical dye (amaranth) from aqueous solution. The material was characterized by X-ray diffraction, nitrogen adsorption-desorption isotherms, and scanning electron microscopy. Several isotherm and kinetic models were tested aiming to represent the amaranth dye adsorption. The prepared sample presented magnetic property, and a mesoporous texture constituted of graphite and three iron-based phases. The adsorption kinetics of amaranth on the adsorbent followed the pseudo-second-order model, whereas the equilibrium data were in good agreement with the BET isotherm, being represented by a sigmoid-shaped adsorption isotherm. The maximum adsorption capacity for the amaranth dye was found to be 44.87 mg g-1, demonstrating that the material prepared in this work showed to be a promising adsorbent for the removal of amaranth from aqueous solution.
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Dotto GL, Meili L, de Souza Abud AK, Tanabe EH, Bertuol DA, Foletto EL. Comparison between Brazilian agro-wastes and activated carbon as adsorbents to remove Ni(II) from aqueous solutions. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 73:2713-2721. [PMID: 27232408 DOI: 10.2166/wst.2016.095] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This research was performed to find an alternative, low-cost, competitive, locally available and efficient adsorbent to treat nickel (Ni) containing effluents. For this purpose, several Brazilian agro-wastes like sugarcane bagasse (SCB), passion fruit wastes (PFW), orange peel (OP) and pineapple peel (PP) were compared with an activated carbon (AC). The adsorbents were characterized. Effects of fundamental factors affecting the adsorption were investigated using batch tests. Kinetic and equilibrium studies were performed using conventional models. It was verified that the adsorption was favored at pH of 6.0 for all agro-wastes, being dependent of the Ni speciation, point of zero charge and surface area of the adsorbents. The Ni removal percentage was in the following order: SCB > OP > AC > PFW > PP. From the kinetic viewpoint, the Elovich model was appropriate to fit the Ni adsorption onto SCB, while for the other adsorbents, the pseudo-first-order model was the most suitable. For all adsorbents, the Langmuir model was the more adequate to represent the equilibrium data, being the maximum adsorption capacities of 64.1 mg g(-1), 60.7 mg g(-1), 63.1 mg g(-1), 48.1 mg g(-1) and 64.3 mg g(-1) for SCB, PFW, OP, PP and AC, respectively. These results indicated that mainly SCB and OP can be used as alternative adsorbents to treat Ni containing effluents.
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da Cruz Severo E, Anchieta CG, Foletto VS, Kuhn RC, Collazzo GC, Mazutti MA, Foletto EL. Degradation of Amaranth azo dye in water by heterogeneous photo-Fenton process using FeWO4 catalyst prepared by microwave irradiation. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 73:88-94. [PMID: 26744938 DOI: 10.2166/wst.2015.469] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
FeWO4 particles were synthesized by a simple, rapid and facile microwave technique and their catalytic properties in heterogeneous photo-Fenton reaction were evaluated. This material was employed in the degradation of Amaranth azo dye. Individual and interactive effects of operational parameters such as pH, dye concentration and H2O2 dosage on the decolorization efficiency of Amaranth dye were evaluated by 2(3) central composite design. According to characterization techniques, a porous material and a well-crystallized phase of FeWO4 oxide were obtained. Regarding the photo-Fenton reaction assays, up to 97% color and 58% organic carbon removal were achieved in the best experimental conditions. In addition, the photo-Fenton process maintained treatment efficiency over five catalyst reuse cycles to indicate the durability of the FeWO4 catalyst. In summary, the results reveal that the synthesized FeWO4 material is a promising catalyst for wastewater treatment by heterogeneous photo-Fenton process.
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Marques Junior JM, Muller ALH, Foletto EL, da Costa AB, Bizzi CA, Irineu Muller E. Determination of propranolol hydrochloride in pharmaceutical preparations using near infrared spectrometry with fiber optic probe and multivariate calibration methods. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2015; 2015:795102. [PMID: 25861516 PMCID: PMC4377514 DOI: 10.1155/2015/795102] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 01/19/2015] [Accepted: 02/13/2015] [Indexed: 06/04/2023]
Abstract
A method for determination of propranolol hydrochloride in pharmaceutical preparation using near infrared spectrometry with fiber optic probe (FTNIR/PROBE) and combined with chemometric methods was developed. Calibration models were developed using two variable selection models: interval partial least squares (iPLS) and synergy interval partial least squares (siPLS). The treatments based on the mean centered data and multiplicative scatter correction (MSC) were selected for models construction. A root mean square error of prediction (RMSEP) of 8.2 mg g(-1) was achieved using siPLS (s2i20PLS) algorithm with spectra divided into 20 intervals and combination of 2 intervals (8501 to 8801 and 5201 to 5501 cm(-1)). Results obtained by the proposed method were compared with those using the pharmacopoeia reference method and significant difference was not observed. Therefore, proposed method allowed a fast, precise, and accurate determination of propranolol hydrochloride in pharmaceutical preparations. Furthermore, it is possible to carry out on-line analysis of this active principle in pharmaceutical formulations with use of fiber optic probe.
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da Silva SS, Chiavone-Filho O, de Barros Neto EL, Foletto EL. Oil removal from produced water by conjugation of flotation and photo-Fenton processes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 147:257-63. [PMID: 25239685 DOI: 10.1016/j.jenvman.2014.08.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 06/05/2014] [Accepted: 08/27/2014] [Indexed: 05/21/2023]
Abstract
The present work investigates the conjugation of flotation and photo-Fenton techniques on oil removal performance from oilfield produced water. The experiments were conducted in a column flotation and annular lamp reactor for induced air flotation and photodegradation steps, respectively. A nonionic surfactant was used as a flotation agent. The flotation experimental data were analyzed in terms of a first-order kinetic rate model. Two experimental designs were employed to evaluate the oil removal efficiency: fractional experimental design and central composite rotational design (CCRD). Overall oil removal of 99% was reached in the optimum experimental condition after 10 min of flotation followed by 45 min of photo-Fenton. The results of the conjugation of induced air flotation and photo-Fenton processes allowed meeting the wastewater limits established by the legislations for disposal.
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Gomes CSM, de Oliveira HNM, Chiavone-Filho O, Foletto EL. Vapor–liquid equilibria for ethyl acetate+methanol and ethyl acetate+ethanol mixtures: Experimental verification and prediction. Chem Eng Res Des 2014. [DOI: 10.1016/j.cherd.2014.07.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Anchieta CG, Cancelier A, Mazutti MA, Jahn SL, Kuhn RC, Gündel A, Chiavone-Filho O, Foletto EL. Effects of Solvent Diols on the Synthesis of ZnFe₂O₄ Particles and Their Use as Heterogeneous Photo-Fenton Catalysts. MATERIALS 2014; 7:6281-6290. [PMID: 28788191 PMCID: PMC5456135 DOI: 10.3390/ma7096281] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/15/2014] [Accepted: 08/18/2014] [Indexed: 11/16/2022]
Abstract
A solvothermal method was used to prepare zinc ferrite spinel oxide (ZnFe₂O₄) using ethylene glycol and 1,4 butanediol as solvent diols, and the influence of diols on the physical properties of ZnFe₂O₄ particles was investigated. The produced particles were characterized by X-ray powder diffraction (XRD), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption isotherms, and the catalytic activity for the organic pollutant decomposition by heterogeneous photo-Fenton reaction was investigated. Both solvents produced particles with cubic spinel structure. Microporous and mesoporous structures were obtained when ethylene glycol and 1,4 butanediol were used as diols, respectively. A higher pore volume and surface area, as well as a higher catalytic activity for the pollutant degradation were found when 1,4 butanediol was used as solvent.
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Luna AJ, Nascimento CAO, Foletto EL, Moraes JEF, Chiavone-Filhoe O. Photo-Fenton degradation of phenol, 2,4-dichlorophenoxyacetic acid and 2,4-dichlorophenol mixture in saline solution using a falling-film solar reactor. ENVIRONMENTAL TECHNOLOGY 2014; 35:364-371. [PMID: 24600876 DOI: 10.1080/09593330.2013.828762] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this work, a saline aqueous solution of phenol, 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenol (2,4-DCP) was treated by the photo-Fenton process in a falling-film solar reactor. The influence of the parameters such as initial pH (5-7), initial concentration of Fe2+ (1-2.5mM) and rate of H202 addition (1.87-3.74mmol min-1) was investigated. The efficiency of photodegradation was determined from the removal of dissolved organic carbon (DOC), described by the species degradation of phenol, 2,4-D and 2,4-DCP. Response surface methodology was employed to assess the effects of the variables investigated, i.e. [Fe2+], [H202] and pH, in the photo-Fenton process with solar irradiation. The results reveal that the variables' initial concentration of Fe2+ and H202 presents predominant effect on pollutants' degradation in terms of DOC removal, while pH showed no influence. Under the most adequate experimental conditions, about 85% DOC removal was obtained in 180 min by using a reaction system employed here, and total removal of phenol, 2,4- and 2,4-DCP mixture in about 30min.
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Weber CT, Collazzo GC, Mazutti MA, Foletto EL, Dotto GL. Removal of hazardous pharmaceutical dyes by adsorption onto papaya seeds. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2014; 70:102-107. [PMID: 25026586 DOI: 10.2166/wst.2014.200] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Papaya (Carica papaya L.) seeds were used as adsorbent to remove toxic pharmaceutical dyes (tartrazine and amaranth) from aqueous solutions, in order to extend application range. The effects of pH, initial dye concentration, contact time and temperature were investigated. The kinetic data were evaluated by the pseudo first-order, pseudo second-order and Elovich models. The equilibrium was evaluated by the Langmuir, Freundlich and Temkin isotherm models. It was found that adsorption favored a pH of 2.5, temperature of 298 K and equilibrium was attained at 180-200 min. The adsorption kinetics followed the pseudo second-order model, and the equilibrium was well represented by the Langmuir model. The maximum adsorption capacities were 51.0 and 37.4 mg g(-1) for tartrazine and amaranth, respectively. These results revealed that papaya seeds can be used as an alternative adsorbent to remove pharmaceutical dyes from aqueous solutions.
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Foletto EL, Weber CT, Bertuol DA, Mazutti MA. Application of Papaya Seeds as a Macro-/Mesoporous Biosorbent for the Removal of Large Pollutant Molecule from Aqueous Solution: Equilibrium, Kinetic, and Mechanism Studies. SEP SCI TECHNOL 2013. [DOI: 10.1080/01496395.2013.808213] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Foletto EL, Battiston S, Mazutti MA, Jahn SL. ADSORPTION OF A LEATHER DYE ON MESOPOROUS STRUVITE OBTAINED FROM SWINE WASTEWATER. CHEM ENG COMMUN 2013. [DOI: 10.1080/00986445.2012.737383] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Linhares B, Weber CT, Foletto EL, Paz DS, Mazutti MA, Collazzo GC. Activated carbon prepared from yerba mate used as a novel adsorbent for removal of tannery dye from aqueous solution. ENVIRONMENTAL TECHNOLOGY 2013; 34:2401-2406. [PMID: 24350496 DOI: 10.1080/09593330.2013.770562] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Activated carbon prepared from yerba mate (Ilex paraguariensis) was used as adsorbent for the removal of tannery dye from aqueous solution. The activated carbon was characterized, and it showed a mesoporous texture, with surface area of 537.4 m2 g(-1). The initial dye concentration, contact time and pH influenced the adsorption capacity. The equilibrium data were in good agreement with both Langmuir and Freundlich isotherms. The adsorption kinetics of the tannery dye on activated carbon prepared from yerba mate followed a pseudo-second-order model. The adsorption process was found to be controlled by both external mass-transfer and intraparticle diffusion, but the external diffusion was the dominating process. This work highlights the potential application of activated carbon produced from yerba mate in the field of adsorption.
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Foletto EL, Weber CT, Paz DS, Mazutti MA, Meili L, Bassaco MM, Collazzo GC. Adsorption of leather dye onto activated carbon prepared from bottle gourd: equilibrium, kinetic and mechanism studies. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2013; 67:201-209. [PMID: 23128640 DOI: 10.2166/wst.2012.555] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Activated carbon prepared from bottle gourd has been used as adsorbent for removal of leather dye (Direct Black 38) from aqueous solution. The activated carbon obtained showed a mesoporous texture, with surface area of 556.16 m(2) g(-1), and a surface free of organic functional groups. The initial dye concentration, contact time and pH significantly influenced the adsorption capacity. In the acid region (pH 2.5) the adsorption of dye was more favorable. The adsorption equilibrium was attained after 60 min. Equilibrium data were analyzed by the Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherm models. The equilibrium data were best described by the Langmuir isotherm, with maximum adsorption capacity of 94.9 mg g(-1). Adsorption kinetic data were fitted using the pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models. The adsorption kinetic was best described by the second-order kinetic equation. The adsorption process was controlled by both external mass transfer and intraparticle diffusion. Activated carbon prepared from bottle gourd was shown to be a promising material for adsorption of Direct Black 38 from aqueous solution.
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Antes FG, Pereira JSF, Diehl LO, Pereira LSF, Boeck P, Guimarães RCL, Guarnieri RA, Ferreira BMS, Santos MDFPD, Foletto EL, Flores EMM. Sediment Removal from Crude Oil Emulsion using Microwave Radiation. J BRAZIL CHEM SOC 2013. [DOI: 10.5935/0103-5053.20130163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Collazzo GC, Foletto EL, Jahn SL, Villetti MA. Degradation of Direct Black 38 dye under visible light and sunlight irradiation by N-doped anatase TIO₂ as photocatalyst. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2012; 98:107-111. [PMID: 22257572 DOI: 10.1016/j.jenvman.2011.12.029] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 12/12/2011] [Accepted: 12/28/2011] [Indexed: 05/31/2023]
Abstract
The N-doped TiO(2) photocatalyst was prepared by calcination of a hydrolysis product composed of titanium (IV) isopropoxide with ammonia as the precipitator. X-ray diffraction, surface area, XPS and UV-vis spectra analyses showed a nanosized anatase structure and the appearance of a new absorption band in the visible region caused by nitrogen doping. The degradation of Direct Black 38 dye on the nitrogen-doped TiO(2) photocatalyst was investigated under visible light and sunlight irradiation. The N-doped anatase TiO(2) demonstrated excellent photocatalytic activity under visible light. Under sunlight irradiation, the N-doped sample showed slightly higher activity than that of the non-doped sample.
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Foletto EL, Collazzo GC, Mazutti MA, Jahn SL. Adsorption of Textile Dye on Zinc Stannate Oxide: Equilibrium, Kinetic and Thermodynamics Studies. SEP SCI TECHNOL 2011. [DOI: 10.1080/01496395.2011.597039] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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