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  1. Article: Rapid enzymatic hydrolysis of crambe oil catalyzed by castor seeds lipases

    Tavares, F. / Sackser, P.R. / Borba, C.E. / Silva, E.A.

    Industrial crops and products. 2021 Nov. 01, v. 171

    2021  

    Abstract: Oil hydrolysis is an important industrial process that requires high temperatures and pressure, or expensive enzymatic catalysts; it is, therefore, necessary to seek the use of inexpensive raw materials and process enhancement. In this work, a rapid and ... ...

    Abstract Oil hydrolysis is an important industrial process that requires high temperatures and pressure, or expensive enzymatic catalysts; it is, therefore, necessary to seek the use of inexpensive raw materials and process enhancement. In this work, a rapid and eco-friendly method, using ultrasound power, was successfully employed to hydrolyze crambe (Crambe abyssinica Hochst.) oil using lipase enzymes directly from castor (Ricinus communis L.) seeds, in oil-free and fresh forms. A yield of 86 % conversion of triglycerides into free fatty acids (FFA) was achieved in 5 min using castor fresh seeds and 73 % of conversion when performing the reaction with oil-free seeds. The operational conditions of ultrasound power, mass ratio of buffer solution and oil, catalyst, and total substrate were evaluated using a central composite rotatable design (CCRD). The hydrolysis yield was optimized by response surface methodology (RSM). The optimum conditions were approximately 70 % of ultrasound power (350 W), 1.79 buffer solution/oil mass ratio, and 0.25 catalyst/substrate mass ratio for fresh seeds. For the oil-free seeds, the optimal conditions found were 68 % (340 W) of ultrasound power, 1.67 buffer solution/oil mass ratio, and 0.06 catalyst/substrate mass ratio. Mathematical modeling was applied to the experimental kinetic data, and it was possible to predict FFA concentration values from independent experiments.
    Keywords Crambe abyssinica ; Ricinus communis ; carboxylic ester hydrolases ; catalysts ; crambe seed oil ; enzymatic hydrolysis ; hydrolysis ; response surface methodology ; ultrasonics
    Language English
    Dates of publication 2021-1101
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1132158-1
    ISSN 1872-633X ; 0926-6690
    ISSN (online) 1872-633X
    ISSN 0926-6690
    DOI 10.1016/j.indcrop.2021.113890
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    In stock of ZB MED Bonn / Germany

    Z 5577: Show issues

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  2. Article: Evaluation of hybrid neutralization/biosorption process for zinc ions removal from automotive battery effluent by dolomite and fish scales

    Ribeiro, C / Alves, H. J / Borba, C. E / Espinoza-Quiñones, F. R / Kroumov, A. D / Módenes, A. N / Scheufele, F. B

    Environmental technology. 2019 Aug. 11, v. 40, no. 18

    2019  

    Abstract: This work focused in the evaluation of Oreochromis niloticus fish scales (FS) as biosorbent material in the removal of Zn from a synthetic effluent based on automotive battery industry effluent and, further, a hybrid neutralization/biosorption process, ... ...

    Abstract This work focused in the evaluation of Oreochromis niloticus fish scales (FS) as biosorbent material in the removal of Zn from a synthetic effluent based on automotive battery industry effluent and, further, a hybrid neutralization/biosorption process, aiming at a high-quality treated effluent, by a cooperative use of dolomite and FS. For this, a physicochemical and morphological characterization (i.e. SEM–EDX, FTIR, XRD, and TXRF) was performed, which helped to clarify a great heterogeneity of active sites (phosphate, carbonate, amide, and hydroxyl) on the biosorbent; also the inorganic constituents (apatites) leaching from the FS was identified. Biosorption results pointed out to a pH-dependent process due to changes in the functional group’s anionic character (i.e. electrostatic interactions), where an initial pH = 3 favored the Zn uptake. Kinetic and equilibrium studies confirmed the heterogeneous surface and cooperative sorption, wherein experimental data were described by Generalized Elovich kinetic model and the favorable isotherm profile by Langmuir–Freundlich isotherm (= 15.38 mg g–1 and). Speciation diagram of Zn species along with the leached species demonstrated that, for the studied pH range, the biosorption was the most likely phenomena rather than precipitation. Finally, the hybrid neutralization/biosorption process showed great potential since both the Zn concentration levels and the pH reached the legislation standards (CZn = 4 mg L–1; pH = 5). Hence, based on the characterization and biosorption results, a comprehensive evaluation of the involved mechanisms in such complex system helped to verify the prospective of FS biosorbent for the Zn treatment from solution, in both individual and hybrid processes.
    Keywords active sites ; batteries ; biosorbents ; biosorption ; carbonates ; dolomite ; electrostatic interactions ; energy-dispersive X-ray analysis ; Fourier transform infrared spectroscopy ; industry ; ions ; kinetics ; leaching ; moieties ; neutralization ; Oreochromis niloticus ; pH ; phosphates ; scales (integument) ; scanning electron microscopy ; X-ray diffraction ; zinc
    Language English
    Dates of publication 2019-0811
    Size p. 2373-2388.
    Publishing place Taylor & Francis
    Document type Article
    ISSN 1479-487X
    DOI 10.1080/09593330.2018.1441332
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  3. Article ; Online: Evaluation of hybrid neutralization/biosorption process for zinc ions removal from automotive battery effluent by dolomite and fish scales.

    Ribeiro, C / Scheufele, F B / Alves, H J / Kroumov, A D / Espinoza-Quiñones, F R / Módenes, A N / Borba, C E

    Environmental technology

    2018  Volume 40, Issue 18, Page(s) 2373–2388

    Abstract: This work focused in the evaluation ... ...

    Abstract This work focused in the evaluation of
    MeSH term(s) Adsorption ; Calcium Carbonate ; Hydrogen-Ion Concentration ; Ions ; Kinetics ; Magnesium ; Prospective Studies ; Water Pollutants, Chemical ; Zinc
    Chemical Substances Ions ; Water Pollutants, Chemical ; Calcium Carbonate (H0G9379FGK) ; Magnesium (I38ZP9992A) ; Zinc (J41CSQ7QDS) ; calcium magnesium carbonate (UG9H2002BF)
    Language English
    Publishing date 2018-02-26
    Publishing country England
    Document type Journal Article
    ISSN 1479-487X
    ISSN (online) 1479-487X
    DOI 10.1080/09593330.2018.1441332
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  4. Article ; Online: Phenomenological modeling of reactive dye adsorption onto fish scales surface in the presence of electrolyte and surfactant mixtures.

    Neves, C V / Scheufele, F B / Nardino, A P / Vieira, M G A / da Silva, M G C / Módenes, A N / Borba, C E

    Environmental technology

    2017  Volume 39, Issue 19, Page(s) 2467–2483

    Abstract: The aim of this work was an experimental and theoretical investigation of the influence of electrolyte (NaCl) and surfactant (SP), as textile auxiliary agents (TAAs), onto reactive blue 5G (RB5G) dye removal by applying untreated fish scales (FS) in ... ...

    Abstract The aim of this work was an experimental and theoretical investigation of the influence of electrolyte (NaCl) and surfactant (SP), as textile auxiliary agents (TAAs), onto reactive blue 5G (RB5G) dye removal by applying untreated fish scales (FS) in batch system. Kinetic and equilibrium studies were performed, aiming at the comprehension of the mass transfer mechanisms through phenomenological modeling. The biosorbent was texturally characterized, to investigate the adsorbent's characteristics and to support the models' assumptions. Hence, a 'physically meaningful' modeling to assess different systems containing dye-TAA mixtures was employed. The experimental results indicated that despite the FS nonporous characteristics, it showed remarkable adsorption capacities (≈291 mg g-1), which may be ascribed to the adsorbent-adsorbate affinity and to dye-aggregates adsorption onto the FS surface. Those results evidence a potential use of FS as an alternative biosorbent material. The mathematical model was able to identify the rate-limiting step of the process; to predict the adsorption kinetics and equilibrium condition, comprising the description of aggregates formation; and to successfully predict kinetic behavior of independent data in simulated real effluent. Those results indicate that the model can be used to simulate operating conditions and, therefore, support the design, optimization, and scale-up of adsorption processes.
    MeSH term(s) Adsorption ; Coloring Agents ; Electrolytes ; Kinetics ; Models, Theoretical ; Surface-Active Agents
    Chemical Substances Coloring Agents ; Electrolytes ; Surface-Active Agents
    Language English
    Publishing date 2017-07-27
    Publishing country England
    Document type Journal Article
    ISSN 1479-487X
    ISSN (online) 1479-487X
    DOI 10.1080/09593330.2017.1356876
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  5. Article: Mathematical modeling of a ternary Cu–Zn–Na ion exchange system in a fixed-bed column using Amberlite IR 120

    Borba, C.E / Santos, G.H.F / Silva, E.A

    Chemical engineering journal. 2012 May 1, v. 189-190

    2012  

    Abstract: The ion exchange dynamics of a ternary Cu²⁺–Zn²⁺–Na⁺ system in a fixed-bed column was described by a mathematical model. The modeling considered the external and internal mass transfer limitations and thermodynamic equilibrium on the liquid–solid ... ...

    Abstract The ion exchange dynamics of a ternary Cu²⁺–Zn²⁺–Na⁺ system in a fixed-bed column was described by a mathematical model. The modeling considered the external and internal mass transfer limitations and thermodynamic equilibrium on the liquid–solid interface, described by the mass action law. To validate the model experimental data were obtained on the ion exchange in a fixed-bed column for the ternary system using Amberlite IR120 resin. In the simulation, none of the model parameters were obtained from fitting to the experimental breakthrough curves of the ternary system. In the model, the values for the external mass transfer coefficients were calculated from empirical relations whereas the internal mass transfer coefficients and mass action law parameters were obtained from the literature, determined from the constitutive binary systems. The model was able to reproduce the experimental breakthrough data under different operating conditions.
    Keywords chemical engineering ; ion exchange ; mass transfer ; mathematical models
    Language English
    Dates of publication 2012-0501
    Size p. 49-56.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 2012137-4
    ISSN 1873-3212 ; 1385-8947
    ISSN (online) 1873-3212
    ISSN 1385-8947
    DOI 10.1016/j.cej.2012.02.017
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  6. Article ; Online: Assessment of metal sorption mechanisms by aquatic macrophytes using PIXE analysis.

    Módenes, A N / Espinoza-Quiñones, F R / Santos, G H F / Borba, C E / Rizzutto, M A

    Journal of hazardous materials

    2013  Volume 261, Page(s) 148–154

    Abstract: In this work, a study of the metal sorption mechanism by dead biomass has been performed. All batch metal biosorption experiments were performed using the aquatic macrophyte Egeria densa as biosorbent. Divalent cadmium and zinc solutions were used to ... ...

    Abstract In this work, a study of the metal sorption mechanism by dead biomass has been performed. All batch metal biosorption experiments were performed using the aquatic macrophyte Egeria densa as biosorbent. Divalent cadmium and zinc solutions were used to assess the sorption mechanisms involved. Using a suitable equilibrium time of 2h and a mixture of 300 mg biosorbent and 50 mL metal solution at pH 5, monocomponent sorption experiments were performed. In order to determine the residual amounts of metals in the aqueous solutions and the concentrations of removed metals in the dry biomass, Particle Induced X-ray Emission (PIXE) measurements in thin and thick target samples were carried out. Based on the strong experimental evidence from the mass balance among the major elements participating in the sorption processes, an ion exchange process was identified as the mechanism responsible for metal removal by the dry biomass.
    MeSH term(s) Adsorption ; Hydrocharitaceae/chemistry ; Ion Exchange ; Metals/chemistry ; Water Pollutants, Chemical/chemistry ; Water Purification
    Chemical Substances Metals ; Water Pollutants, Chemical
    Language English
    Publishing date 2013-10-15
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1491302-1
    ISSN 1873-3336 ; 0304-3894
    ISSN (online) 1873-3336
    ISSN 0304-3894
    DOI 10.1016/j.jhazmat.2013.07.020
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  7. Article: Application of the mass action law to describe ion exchange equilibrium in a fixed-bed column

    Borba, C.E / Silva, E.A / Spohr, S / Santos, G.H.F / Guirardello, R

    Chemical engineering journal. 2011 Aug. 1, v. 172, no. 1

    2011  

    Abstract: Ion exchange experiments were carried out in a fixed-bed column employing the binary systems Cu²⁺–Na⁺ and Zn²⁺–Na⁺. Amberlite IR 120 was used as the ion exchange resin. The ion exchange dynamics within the column was described by a model considering the ... ...

    Abstract Ion exchange experiments were carried out in a fixed-bed column employing the binary systems Cu²⁺–Na⁺ and Zn²⁺–Na⁺. Amberlite IR 120 was used as the ion exchange resin. The ion exchange dynamics within the column was described by a model considering the external mass transfer and the diffusion within the particle. A linear driving force model was used to represent the mass transfer within the resin particles. The model considered the thermodynamic equilibrium on the liquid–solid interface, which was described by the Langmuir isotherm and by the mass action law. The results indicate that both models represent well the ion exchange dynamics in all cases.
    Keywords chemical engineering ; ion exchange ; ion exchange resins ; mass transfer ; models ; sorption isotherms
    Language English
    Dates of publication 2011-0801
    Size p. 312-320.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 2012137-4
    ISSN 1873-3212 ; 1385-8947
    ISSN (online) 1873-3212
    ISSN 1385-8947
    DOI 10.1016/j.cej.2011.06.002
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  8. Article: Assessment of metal sorption mechanisms by aquatic macrophytes using PIXE analysis

    Módenes, A.N / Espinoza-Quiñones, F.R / Santos, G.H.F / Borba, C.E / Rizzutto, M.A

    Journal of hazardous materials. 2013 Oct. 15, v. 261

    2013  

    Abstract: In this work, a study of the metal sorption mechanism by dead biomass has been performed. All batch metal biosorption experiments were performed using the aquatic macrophyte Egeria densa as biosorbent. Divalent cadmium and zinc solutions were used to ... ...

    Abstract In this work, a study of the metal sorption mechanism by dead biomass has been performed. All batch metal biosorption experiments were performed using the aquatic macrophyte Egeria densa as biosorbent. Divalent cadmium and zinc solutions were used to assess the sorption mechanisms involved. Using a suitable equilibrium time of 2h and a mixture of 300mg biosorbent and 50mL metal solution at pH 5, monocomponent sorption experiments were performed. In order to determine the residual amounts of metals in the aqueous solutions and the concentrations of removed metals in the dry biomass, Particle Induced X-ray Emission (PIXE) measurements in thin and thick target samples were carried out. Based on the strong experimental evidence from the mass balance among the major elements participating in the sorption processes, an ion exchange process was identified as the mechanism responsible for metal removal by the dry biomass.
    Keywords Egeria densa ; X-radiation ; aqueous solutions ; biomass ; biosorbents ; biosorption ; cadmium ; ion exchange ; macrophytes ; pH ; zinc
    Language English
    Dates of publication 2013-1015
    Size p. 148-154.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1491302-1
    ISSN 1873-3336 ; 0304-3894
    ISSN (online) 1873-3336
    ISSN 0304-3894
    DOI 10.1016/j.jhazmat.2013.07.020
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  9. Article ; Online: Thin and thick target PIXE analyses to assess the mechanism of Cu2+ removal by Egeria densa.

    Espinoza-Quiñones, F R / Módenes, A N / Santos, G H F / Borba, C E / Rizzutto, M A / Ravagnani, Mauro A S S

    Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine

    2013  Volume 82, Page(s) 1–6

    Abstract: In this work the PIXE technique was used to study the mechanism of metal sorption by dead biomass. Several batch copper-sorption experiments were performed by using Egeria densa biomass. PIXE measurements were performed in solid and liquid samples. ... ...

    Abstract In this work the PIXE technique was used to study the mechanism of metal sorption by dead biomass. Several batch copper-sorption experiments were performed by using Egeria densa biomass. PIXE measurements were performed in solid and liquid samples. Element concentrations in biosorbent samples were determined using the Clara software. Based on the mass balance among the major elements in the liquid and solid phases before and after the Cu-removal experiments, an ion exchange process is suggested as the main mechanism.
    MeSH term(s) Adsorption ; Biomass ; Copper/isolation & purification ; Environmental Pollutants/isolation & purification ; Hydrocharitaceae ; Ion Exchange Resins ; Spectrometry, X-Ray Emission/methods ; Spectrometry, X-Ray Emission/statistics & numerical data
    Chemical Substances Environmental Pollutants ; Ion Exchange Resins ; Copper (789U1901C5)
    Language English
    Publishing date 2013-12
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 1142596-9
    ISSN 1872-9800 ; 0883-2889 ; 0969-8043
    ISSN (online) 1872-9800
    ISSN 0883-2889 ; 0969-8043
    DOI 10.1016/j.apradiso.2013.07.021
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    In stock of ZB MED Cologne/Königswinter

    Ue I Zs.279: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
    ab Jg. 2022: Lesesaal (EG)

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  10. Article: Adsorption of Zn(II) and Cd(II) ions in batch system by using the Eichhornia crassipes.

    Módenes, A N / Espinoza-Quiñones, F R / Borba, C E / Trigueros, D E G / Lavarda, F L / Abugderah, M M / Kroumov, A D

    Water science and technology : a journal of the International Association on Water Pollution Research

    2011  Volume 64, Issue 9, Page(s) 1857–1863

    Abstract: In this work, the displacement effects on the sorption capacities of zinc and cadmium ions of the Eichornia crassipes-type biosorbent in batch binary system has been studied. Preliminary single metal sorption experiments were carried out. An improvement ... ...

    Abstract In this work, the displacement effects on the sorption capacities of zinc and cadmium ions of the Eichornia crassipes-type biosorbent in batch binary system has been studied. Preliminary single metal sorption experiments were carried out. An improvement on the Zn(II) and Cd(II) ions removal was achieved by working at 30 °C temperature and with non-uniform biosorbent grain sizes. A 60 min equilibrium time was achieved for both Zn(II) and Cd(II) ions. Furthermore, it was found that the overall kinetic data were best described by the pseudo second-order kinetic model. Classical multi-component adsorption isotherms have been tested as well as a modified extended Langmuir isotherm model, showing good agreement with the equilibrium binary data. Around 0.65 mequiv./g maximum metal uptake associated with the E. crassipes biosorbent was attained and the E. crassipes biosorbent has shown higher adsorption affinity for the zinc ions than for the cadmium ones in the binary system.
    MeSH term(s) Adsorption ; Batch Cell Culture Techniques/methods ; Biodegradation, Environmental ; Cadmium/isolation & purification ; Eichhornia/metabolism ; Ions ; Kinetics ; Models, Chemical ; Surface Properties ; Temperature ; Zinc/isolation & purification
    Chemical Substances Ions ; Cadmium (00BH33GNGH) ; Zinc (J41CSQ7QDS)
    Language English
    Publishing date 2011
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 764273-8
    ISSN 1996-9732 ; 0273-1223
    ISSN (online) 1996-9732
    ISSN 0273-1223
    DOI 10.2166/wst.2011.764
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    Einzelsignatur: Show issues

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