Papers by Fabiano Bisinella Scheufele
Process Biochemistry, Nov 1, 2016
Abstract Green energy production connected with global warming is one of the hottest topics for i... more Abstract Green energy production connected with global warming is one of the hottest topics for industry, technology, and life science. Microalgae culture and its potential for industrial applications in CO2 fixation from flue gases for second generation biofuels and many other valuable metabolites’ production has received much attention in recent years. The goal of this review is to combine all the key knowledge obtained in state of the art studies in recent years about the modeling of photobioreactors (PBRs). In order to develop the complex PBR phenomenological model, we considered it as a system and applied the theory of system analysis on PBR. Special attention was given to decomposition principles of this theory where the PBR system was divided into sub-systems. Furthermore, this review shows how to combine the knowledge from modeling of sub-systems by taking into account relationships between them, and how such interrelationships influence the overall PBR modeling procedure for the particular microalgal cultivation process. The result of this work is a successful development of a complex PBR phenomenological model, which was presented as an independent original authors’ work.
DOAJ (DOAJ: Directory of Open Access Journals), Mar 1, 2012
<p class="aresumo">A soja possui ampla disponibilidade de componentes bioquímicos... more <p class="aresumo">A soja possui ampla disponibilidade de componentes bioquímicos como proteínas, polissacarídeos, lipídios, carboidratos, minerais, vitaminas, fibras, lecitina, dentre outros, tornando interessante sua utilização como substrato para a fermentação em estado sólido (FES). Este processo, apesar de não ser tão utilizado industrialmente quanto à fermentação submersa (Fsm), apresenta-se viável, pois tem apresentado resultados superiores de produtividade, principalmente no cultivo de fungos filamentosos e na produção de enzimas. Assim, o objetivo deste trabalho foi o de comparar a produção de diferentes tipos de complexos enzimáticos por FES utilizando diferentes tipos de sojas (orgânica, transgênica e convencional) com o fungo <em>Aspergillus niger</em>. Realizou-se a caracterização dos substratos para a produção de amilase, protease e lipase, avaliação das curvas de crescimento do microrganismo e das condições ótimas de produção da protease utilizando planejamento de experimentos. As maiores atividades enzimáticas no estudo dos parâmetros da fermentação foram observadas para a protease, utilizando soja convencional com umidade inicial de 50%, 144h de fermentação, concentração inicial do inóculo de 4.10<sup>6</sup> esporos g<sup>-1</sup> e tamanho de partícula de 0,6 mm. O estudo de otimização do processo indicou que os melhores resultados de atividade enzimática para a protease foram obtidos em pH 3,0 e tamanho de partícula dos grãos de soja de 0,6 mm após a fragmentação para as fermentações.</p>
Determinação do conteúdo de açúcares redutores totais (ART) ... 3.12.6 Determinação da atividade ... more Determinação do conteúdo de açúcares redutores totais (ART) ... 3.12.6 Determinação da atividade enzimática (AE) total em papel filtro .. 3.12.7 Determinação do conteúdo de hemicelulose .
Environmental Technology, Feb 26, 2018
(F.B. Scheufele). (=15.38 mg g-1 and. Speciation diagram of Zn species along with the leached spe... more (F.B. Scheufele). (=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 (C Zn =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 Zn treatment from solution, in both individual and hybrid process.
Chemical Engineering Journal, 2017
This work focused in the assessment of the potential of reactive blue dye 5G (RB5G) adsorption by... more This work focused in the assessment of the potential of reactive blue dye 5G (RB5G) adsorption by polymeric adsorbent Dowex Optipore SD-2 (DOSD-2) in closed batch system by a phenomenological investigation of the adsorption process by both experimental data and mathematical modeling of kinetics, equilibrium and thermodynamics. The kinetic model of adsorption on the adsorbent sites described experimental data, consequently the adsorption itself is the rate-limiting step of the
Este trabalho teve como objetivo a avaliação da cinética e equilíbrio do processo de secagem do b... more Este trabalho teve como objetivo a avaliação da cinética e equilíbrio do processo de secagem do bagaço com a finalidade de melhorar a sua eficiência num processo de remoção do corante têxtil. Os experimentos de cinética foram realizados em estufa com circulação de ar, em camada fina. O equilíbrio de sorção de umidade foi determinado pelo método estático, entre 35 e 65°C. Para todas as temperaturas avaliadas, o processo de secagem apresentou período de taxa de secagem decrescente, o qual foi melhor representado pelo modelo Dois Termos. Os valores de difusividade variaram entre 6,47.10-9 e 3,97.10-8 m 2 s-1 e a energia de ativação foi 30,20 kJ mol-1. Os dados de equilíbrio apresentaram dependência da temperatura, com isotermas no formato sigmoidal melhor representados pelo modelo de Oswin. Em todas as temperaturas avaliadas, o processo de secagem apresentou cinética favorável, viabilizando sua utilização como adsorvente.
Materials advances, 2021
Templated porous carbon materials (TPCMs) have recently received attention due to their many appl... more Templated porous carbon materials (TPCMs) have recently received attention due to their many applications. In this context, this work focused on the development of a simple synthesis method to produce highly porous carbon materials, by applying commercial sugar as a carbon source, pyrolyzed silica (as a template) and deionized water. The synthesis of the materials consisted of: (i) gel formation, wherein the mass ratio sugar/template (S/T) was evaluated as well as the deionized water volume; (ii) carbonization: the gels were carbonized under an N 2 inert atmosphere at a heating rate of 10 1C min À1 and a temperature of 700 1C for 1 h; and (iii) template leaching, in which two leaching agents were evaluated (NaOH and HF) for silica template removal. In order to evaluate the potential and characteristics of the TPCMs, morphological, textural and chemical characterization were carried out through N 2 and CO 2 physisorption, Raman spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Overall, the NaOH-leached materials reached similar chemical and textural properties when compared to the HF, which is interesting from the economical, safety and environmental points of view. The N 2 physisorption analyses evidenced the synthesis of a highly porous material after the removal of the template; C1-I (NaOH leaching) showed a specific surface area of 462 m 2 g À1 and a micropore area of 610 m 2 g À1 , and elevated pore volume (1.04 cm 3 g À1), wherein micropores (0.21 cm 3 g À1) and mesopores (0.83 cm 3 g À1) were identifiedmost interesting values for the best TPCM amongst the studied conditions. An average diameter value of ultramicropores and supermicropores (2.9 Å) was also identified by CO 2 physisorption. The XRD diffractograms and Raman analyses indicated the formation of a semi-crystalline structure in the templated porous carbon material (TPCM), with large domains of graphite and graphene oxide sheets in a random pattern (turbostratic), along with amorphous carbon. From the FT-IR analysis it was possible to determine that the carbonized samples underwent partial oxidation and to identify the presence of bonds and vibrations of the aromatic skeleton (nOH, nC-H and nCQC). Overall, the characterization of the TPCMs, produced from simple raw materials, have demonstrated the great potential of this synthesis method for highly porous carbonaceous materials.
Separation and Purification Technology, Dec 1, 2018
The objective of this work was to maximize the efficiency of the ciprofloxacin (CIP) removal in f... more The objective of this work was to maximize the efficiency of the ciprofloxacin (CIP) removal in fixed-bed column, packed with SGC650H resin, by the optimization of the volumetric flow rate (Q) and bed height (H bed). For this, a hybrid procedure based on statistical and phenomenological modeling was used. Based on a central composite rotatable design (CCRD) the conditions of Q and H bed were defined to obtain breakthrough curves, wherein only 8 of a total of 11 assays were experimentally obtained. Based on the resin textural characterization and molecular dimensions analysis of the ciprofloxacin, phenomenological models were employed to describe the experimental data. The most accurate mathematical model for the breakthrough curves description, namely, adsorption on the sites model (AS) was validated with the experimental results of the CCRD and further used to predict other experimental 2 conditions. For this, independent experiments were performed to evaluate the proposed methodology, which demonstrated a predictive capacity of the model and allowed the fixed-bed column performance optimization, achieving a maximum efficiency of 81.5%. In general, the presented data may be useful for the development of fixed-bed systems. In addition, the results evidenced the potential of the adsorption process for trace-level pollutants treatment, due to elevated CIP adsorption capacities and high affinity to the SGC650H resin as well as favorable kinetics. Besides, by applying predictive phenomenological modeling, the hybrid proposed approach presents a perspective to support the optimization and scale-up of fixed-bed column operation, thus allowing the application of the treatment method in industrial scale.
Journal of Materials Science, Feb 26, 2018
We present a feasibility study of different adsorbent materials, namely residual fish scales bios... more We present a feasibility study of different adsorbent materials, namely residual fish scales biosorbent (FS), mineral dolomite (DL) and commercial resin (CR) in the heavy metals removal in multicomponent solution based on the properties of a real effluent from automotive battery recycling industry. Considering the effluent complex characteristics, the materials were assessed aiming to provide not only the heavy metals removal, but also the effluent neutralization and lower sludge generation. For this, all the studied materials were physicochemically and morphologically characterized with the aim of understanding the mechanisms involved in the process. Further, the elemental compositions of the solid and liquid phases generated from each treatment process were assessed by X-ray fluorescence spectrometry. The effluent presented highly acidic characteristics and heavy metals above the legislated limits for discharge (Fe, Zn and Pb). Each adsorbent material followed different mechanisms which led to dissimilar removal and neutralization capacities. The CR showed remarkable heavy metals removal capacity governed by an ion exchange mechanism; conversely, it did not show a neutralization effect. In contrast, FS and DL presented lower removal capacities by complex simultaneous phenomena (ion exchange, precipitation and/or complexation), but a great neutralization potential related to leaching of alkaline constituents. When sludge generation is considered as a key factor, mitigation and enhancement of treated effluent quality could
Acta Scientiarum-technology, Feb 26, 2021
The objective of this work was to evaluate the ability of CCC as an adsorbent material for the ac... more The objective of this work was to evaluate the ability of CCC as an adsorbent material for the acidity removal of RFO, aiming at the application of the oil in biodiesel production. For that, a RCCD was used for FFA removal by applying the CCC and CAC for comparative purposes. In the RCCD removal assays the effect of the Temperature, Agitation and Mass factors were assessed over acidity removal of the oil. Under the best conditions from RCCD, an evaluation of adsorption kinetics was performed, wherein it was observed the equilibrium was reached within 4 h, for the CCC. Also, the influence of the adsorbent dosage was performed. It was verified that 4 g was sufficient to allow the system to reach the maximum FFA removal. Overall, the CCC presented results approximately twice as high than those obtained by the CAC, mainly due to the pore size distribution which led to a "molecular sieving effect" for the CCC adsorbent. It allowed the major diffusion of the FFA molecules inside its narrow-distributed pores, whereas the CAC with a wider pore distribution (up to 260 Å) resulted in the larger molecules competition for the active sites inside the porous structure. The adsorbents' characterization also evidenced that CCC adsorbent presented a higher content of oxygenated groups in its surface which acted as potential active sites for the FFA molecules resulting in an enhanced adsorbent-adsorbate affinity. Lastly, the wastes generated in the adsorption experiments, were evaluated as to their calorific power resulting in a value of 31,933 J g-1 , suggesting that it could be further used for energetic purposes, such as a solid fuel for boilers and furnaces to generate thermal energy. Based on these results, the CCC stands out as a promising material for RFO acidity removal.
Fuel, May 1, 2021
Abstract The aim of this work was to evaluate the effect of the acidic surface oxygenated groups ... more Abstract The aim of this work was to evaluate the effect of the acidic surface oxygenated groups and textural properties onto the adsorbent surface towards dibenzothiophene removal. The samples were prepared from an activated carbon derived from coconut shell (AC), by oxidative (ACO) and thermal (ACT) treatments. Morphological and chemical analyses were performed to characterize the adsorbents. The adsorption experiments were carried out in batch and closed system. The Langmuir isotherm model was used to describe equilibrium data, while kinetic data were described by the Homogeneous Surface Diffusion Model. The characterization results indicated that the adsorbents are predominantly microporous materials with effective surface area higher than 750 m2 g−1 (AC = 753 m2 g−1, ACT = 802 m2 g−1, ACO = 755 m2 g−1). It was observed a decrease in the amount of oxygenated functional groups in the ACT (310 µmol g−1) in relation to AC (738 µmol g−1), while for the ACO this amount was increased (2630 µmol g−1). The insertion of oxygenated functional groups on the adsorbent’s surface promoted an increment of density of sites (AC = 0.98 µmol m−2, ACT = 0.38 µmol m−2, ACO = 3.48 µmol m−2) what, consequently, led to the enhancement of the adsorption capacity. Also, the oxidative treatment provided a more favorable mass transfer kinetics with an increase of 89% enhancement for the diffusivity coefficient. These results indicate that an increase of effective specific surface area and acidic oxygenated groups can improve the adsorption performance of the carbon-based adsorbents for desulfurization purposes.
Engineering in Life Sciences, Sep 25, 2018
Modeling as a tool solves extremely difficult tasks in life sciences. Recently, schemes of cultur... more Modeling as a tool solves extremely difficult tasks in life sciences. Recently, schemes of culturing of microalgae have received special attention because of its unique features and possible uses in many industrial applications for renewable energy production and high value products isolation. The goal of this review is to present the use of system analysis theory applied to microalgae culturing modeling and process development. The review mainly focuses on the modeling of the key steps of autotrophic growth under the integral biorefinery concept of the microalgae biomass. The system approach follows systematically a procedure showing the difficulties by modeling of subsystems. The development of microalgae kinetics and computational fluid dynamics (CFD) studies were analyzed in details as subsystems in advanced design of photobioreactor (PBR). This review logically follows the trends of the modeling procedure and clarifies how this approach may save time and money during the research efforts. The result of this work is a successful development of a complex PBR mathematical analysis in the frame of the integral biorefinery concept.
Chemical Engineering Journal, 2016
A phenomenological model for multilayer liquid phase adsorption in closed and batch system was de... more A phenomenological model for multilayer liquid phase adsorption in closed and batch system was developed to assess the diffusional resistances and the adsorption rate-limiting steps. Equilibrium, kinetic and thermodynamic results indicated a multilayer adsorption behavior, wherein two adsorption steps were identified: (i) monolayer adsorption, with chemisorption characteristic binding energy due to synergistically electrostatic and H-bond intermolecular interactions; (ii) multilayer adsorption, favored by high dye concentrations and temperatures, however presenting a physical biding energy, related to less intense interactions such as H-bond and van der Waals forces. Additionally, dye aggregation in the liquid phase was observed and investigated. The proposed adsorption model allowed to investigate physically the kinetics, equilibrium and thermodynamics through a unique approach and to elucidate the mechanisms in distinct operational conditions. Hence, this mechanistic and predictive model can be used for the optimization and scale-up of the multilayer adsorption processes.
Environmental Technology, Oct 5, 2022
RESUMO-A contaminação dos corpos aquáticos é um problema amplamente presente no setor industrial ... more RESUMO-A contaminação dos corpos aquáticos é um problema amplamente presente no setor industrial têxtil. Dentre os métodos de tratamento, a adsorção se destaca pela flexibilidade, simplicidade de projeto e maior remoção de substâncias orgânicas. O objetivo do trabalho foi a avaliação da adsorção do corante reativo Azul 5G pela escama de Oreochromis niloticus em leito fixo. Os experimentos foram realizados variando-se as concentrações da solução de corante na faixa entre 50 e 125 mg L-1. Os demais parâmetros foram fixados nos valores: pH 2,0, vazão 4 mL min-1 , massa de adsorvente 1,5 g e altura do leito 11 cm. Empregou-se aos dados experimentais de adsorção um modelo fenomenológico de difusão no sólido, o qual descreveu adequadamente o processo nas condições avaliadas. Obteve-se uma capacidade máxima de adsorção de 343,43 mg g-1 e tempo de ruptura superiores à 20 h indicando um elevado potencial de adsorção do material, quando comparado a outros adsorventes, que aliado a alta disponibilidade do resíduo na região, justifica a sua aplicação no tratamento de efluentes.
Environmental Engineering and Management Journal, 2018
The macrophyte Pistia stratiote was used as biosorbent for the removal of Black Krom KJR (BK-KJR)... more The macrophyte Pistia stratiote was used as biosorbent for the removal of Black Krom KJR (BK-KJR) dye in synthetic aqueous solution. Initially, some tests were performed to verify the best operational conditions such as pH, biosorbent particle size, sorption temperature and stirring speed, which were later used in the kinetic and equilibrium tests. All tests were performed in duplicate. The highest removal rates of the pollutant were achieved at the process conditions of initial pH 2, granulometric mixture of roots, 30 °C and stirring speed of 80 rpm. In the kinetic test an equilibrium time of 24 h was found. The kinetic data were adjusted by applying the pseudo-first order, pseudo-second order and Elovich models, and as a result the best fit was found with the pseudo-second order model. In the equilibrium study it was found that, among the tested models, Langmuir model was the one that best fitted the experimental data, with a maximum sorption capacity (qmax) of 84.11 ± 1.64 mg g-1 and affinity constant (b) 0.025 ± 0.001 mg L-1. These results showed high potential of the macrophyte Pistia sp. as an alternative material to remove the BK-KJR dye.
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Papers by Fabiano Bisinella Scheufele