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27 results on '"de Sant'Ana, Hosiberto Batista"'

15. Aqueous two‐phase anthocyanins partitioning from açai – laboratory scale‐up.

Author

de Abreu Siqueira, Ana Cristina, Leite, Kennedy Moreira, Braga, Anna Rafaela Cavalcante, Ribeiro, Paulo Riceli Vasconcelos, Julião, Guilherme Zocollo, de Brito, Edy Sousa, da Silva, Ivanildo José, and de Sant'Ana, Hosiberto Batista

Subjects
ANTHOCYANINS, AMMONIUM sulfate, CYANIDIN, SUGARS
Abstract

Summary: Açai, a fruit typical of Amazonia in Brazil, is consumed due to beneficial health effects. Aqueous two‐phase systems (ATPS) based on ethanol (28% w/w) and ammonium sulfate (17.5% w/w) were employed in the partitioning of anthocyanins from açai. Experiments, applying 50 mL equilibrium cells and a 1‐L glass vessel reactor, evaluated anthocyanin partition feasibility on a laboratory scale‐up. The anthocyanin preferentially moved to the top (ethanol‐rich phase) and sugars to the bottom (ammonium sulfate‐rich phase). Scale‐up effects were compared with the equilibrium cell experiments with anthocyanin extraction yielding more than 64% w/w, the yield of sugars in the bottom phase (>61% w/w) and removal of sugars (97%), showing the feasibility for the scale‐up process. The anthocyanin profile from açai, ATPS partition on the bench scale and laboratory scale‐up evaluated by UPLC‐QTOF‐MS identified cyanidin, peonidin and pelargonidin derivatives. [ABSTRACT FROM AUTHOR]

Published
2023
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25. Evaluation of AISI 316L stainless steel welded plates in heavy petroleum environment

Author

Silva, Cleiton Carvalho, Farias, Jesualdo Pereira, and de Sant’Ana, Hosiberto Batista

Subjects
*AUSTENITIC stainless steel, *WELDING, *STRUCTURAL plates, *ALLOYS, *CORROSION resistant materials, *PETROLEUM chemicals, *SCANNING electron microscopy, *X-ray spectroscopy, *MICROSTRUCTURE
Abstract

Abstract: This work presents the study done on the effect of welding heating cycle on AISI 316L austenitic stainless steel corrosion resistance in a medium containing Brazilian heavy petroleum. AISI 316L stainless steel plates were welded using three levels of welding heat input. Thermal treatments were carried out at two levels of temperatures (200 and 300°C). The period of treatment in all the trials was 30h. Scanning electronic microscopy (SEM) and analysis of X-rays dispersive energy (EDX) were used to characterize the samples. Weight loss was evaluated to determine the corrosion rate. The results show that welding heating cycle is sufficient to cause susceptibility to corrosion caused by heavy petroleum to the heat affected zone (HAZ) of the AISI 316L austenitic stainless steel. [Copyright &y& Elsevier]

Published
2009
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26. Pore-expanded SBA-15 for the immobilization of a recombinant Candida antarctica lipase B: Application in esterification and hydrolysis as model reactions.

Author

Saraiva Rios, Nathalia, Pessoa Pinheiro, Maisa, Bezerra Lima, Magno Luís, Guimarães Freire, Denise Maria, Júniorda Silva, Ivanildo José, Rodríguez-Castellón, Enrique, de Sant’Ana, Hosiberto Batista, Casimiro Macedo, André, and Barros Gonçalves, Luciana Rocha

Subjects
*ENCAPSULATION (Catalysis), *CANDIDA, *ESTERIFICATION, *ENZYMES, *HYDROLYSIS
Abstract

A pore-expanded mesoporous silica (SBA-15) was investigated for the immobilization of a recombinant Candida antarctica lipase B (LIPB). The influence of contact time and medium pH during adsorption, as well as thermal and solvent stability of the immobilized enzyme were evaluated. The best prepared biocatalyst was then evaluated in a model esterification reaction, the production of two flavour esters (e.g. methyl and ethyl butyrate) and in a model hydrolysis reaction, the ethyl hexanoate hydrolysis. The biocatalyst maintained high activity and operational stability even after five successive cycles of synthesis. A commercial C. antarctica lipase B was also immobilized on SBA-15 and evaluated under the same conditions, achieving similar volumetric productivities. In addition, the biocatalyst SBA-15-LIPB was tested in ethyl hexanoate hydrolysis. The influence of reactional medium pH was conducted (pH 5, 7 and 9.2) and the highest biocatalyst activity was at pH 5 (about 636.3 U/g enzyme ). SBA-15-LIPB and SBA-15-LIPB-GA (crosslinked biocatalyst) were reused for 5 cycles, retaining, after the third cycle, 56.6 and 76.80%, respectively, of its initial activity. The prepared biocatalysts were able to catalyze the model reactions (esterification and hydrolysis) with high activity and reasonable stability. [ABSTRACT FROM AUTHOR]

Published
2018
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27. Optimization of the methylic biodiesel purification process by intermediate of liquid–liquid equilibrium data for ternary systems containing methanol+water+(soybean, corn or brown shell of coconut) biodiesel.

Author

Pinheiro, Regiane Silva, Bessa, Aline Mara Maia, de Queiroz, Bruna Amaral, Duarte, Aíla Maria Souza Fontenele, de Sant’Ana, Hosiberto Batista, and de Santiago-Aguiar, Rílvia Saraiva

Subjects
*MATHEMATICAL optimization, *BIODIESEL fuels, *INTERMEDIATES (Chemistry), *LIQUID-liquid equilibrium, *DATA analysis, *TERNARY system, *METHANE, *WATER
Abstract

Highlights: [•] LLE data has been studied in order to optimize biodiesel purification process. [•] LLE data were correlated with different activity coefficient models. [•] The influence of temperature plays a minor role on the purification process. [•] The use of methanol as extractor can accelerate the purification of biodiesel. [Copyright &y& Elsevier]

Published
2014
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