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Made available in DSpace on 2020-12-12T02:08:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Activated charcoal was prepared from Acrocomia aculeata (macaúba) endocarp by ZnCl2 activation and then used for the adsorptive purification of pretreated crude glycerol (CG) containing pigments, such as β-carotene. The pretreatment of glycerol involved filtration of the K3PO4 formed by the addition of H3PO4 to the crude glycerol containing KOH. A mixture of 1.38:1 w/w of ZnCl2:Acrocomia aculeata pulp was heated at 120 °C with stirring for 24 h. The mixture was activated by heating at 600 °C for 3 h. The activated charcoal was cooled to 25 °C, washed with a 1:1 mixture of methanol and water (100 mL) and heated at 150 °C for 2 h. The surface properties of the activated charcoal (surface area 627 m2 g−1, pore volume 0.39 m3 g−1, Bronsted sites 118.23 μmol g−1, and Lewis sites 104.86 μmol g−1) and the adsorption capacity for impurities in H3PO4-pretreated crude glycerol were investigated. The activated charcoal exhibited the most suitable surface properties for the purification of pretreated crude glycerol, attaining a 95.99% glycerol concentration (by GC) using 10 g/L with gravity filtration through a column at room temperature over a 48-h period. The purified glycerol was characterized by GC/MS, 1H- and 13C-NMR, and DSC and TG analyses. The activated charcoal was regenerated by washing with methanol and hexane and heating to 150 °C for 5 h. The activated charcoal could be re-used three times to remove all of the pigments before it was necessary to re-activate the charcoal by heating with ZnCl2. Department of Pharmacy Universidade Federal dos Vales do Jequitinhonha e Mucuri-UFVJM Campus JK, Rodovia MGT 367-Km 583, N° 5000, Alto da Jacuba Department of General and Inorganic Chemistry Institute of Chemistry São Paulo State University-Unesp, R. Prof. Francisco Degni 55, Quitandinha Department of Physics and Chemistry Faculdade de Ciências Farmacêuticas de Ribeirão Preto São Paulo University-USP, Av. Do Café s/n Universidade de Franca, Av. Dr. Armando Sales Oliveira, 201, C.P. 82 Laboratório de Química Bioinorgânica Departamento de Química Faculdade de Filosofia Ciências e Letras de Ribeirão Preto Universidade de São Paulo, Av. Bandeirantes, 3900 USTAR Bioenergy Center Biological Engineering Utah State University Research Institute for Medicines (iMed.ULisboa) Faculty of Pharmacy Universidade de Lisboa, Av. Prof. Gama Pinto Faculdade de Ciências Farmacêuticas Alimentos e Nutrição Universidade Federal de Mato Grosso do Sul-UFMS, Av. Costa e Silva, s.n Department of General and Inorganic Chemistry Institute of Chemistry São Paulo State University-Unesp, R. Prof. Francisco Degni 55, Quitandinha

SiO

Made available in DSpace on 2019-10-06T16:09:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-01 Amorphous SiO2-SO3H [1] with a small surface area and 1.32-mmol H+/g was used for the one-step preparation of solketal from glycerol and acetone; a 20%-w/w catalyst mixture (10% [1] and 10% (Bu4N)(BF4) was found to be very efficient for the synthesis of disolketal ether and of oxygenated biofuels fatty acids solketal esters (FASEs), by direct esterification of the caprylic, lauric, stearic, oleic and linoleic acids with solketal in a 4:1 acid:solketal ratio in refluxing toluene. Solketal acetate was also produced in quantitative yields. Department of Pharmacy Universidade Federal dos Vales do Jequitinhonha e Mucuri-UFVJM, R. da Glória, 187, CEP-39 Department of General and Inorganic Chemistry Institute of Chemistry São Paulo State University-Unesp, R. Prof. Francisco Degni 55, Quitandinha, CEP-14 Department of Physics and Chemistry Faculdade de Ciências Farmacêuticas de Ribeirão Preto São Paulo University-USP, Av. do Café s/n, CEP-14 Department of General and Inorganic Chemistry Institute of Chemistry São Paulo State University-Unesp, R. Prof. Francisco Degni 55, Quitandinha, CEP-14

Made available in DSpace on 2021-06-25T10:50:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 SiO2-SO3H, with a surface area of 115 m2/g, pore volumes of 0.38 cm3g−1 and 1.32 mmol H+/g, was used as a 10% w/w catalyst for the preparation of 5-hydroxymethyl-2-furfural (HMF) from fructose. A conversion of 100% was achieved in a microwave reactor during 10 min at 150 °C in DMSO, with 100% selectivity for HMF, at a molar ratio of fructose: DMSO equal to 1:56. The catalyst could be re-used three times. Department of Pharmacy Universidade Federal dos Vales do Jequitinhonha e Mucuri-UFVJM, Campus JK, Rodovia MGT 367 - Km 583, nº 5.000, Alto da Jacuba Department of General and Inorganic Chemistry Institute of Chemistry São Paulo State University-Unesp, R. Prof. Francisco Degni 55, Quitandinha Department of Physics and Chemistry Faculdade de Ciências Farmacêuticas de Ribeirão Preto São Paulo University-USP, Av. do Café s/n Faculdade de Ciências Farmacêuticas Alimentos e Nutrição Universidade Federal do Mato Grosso do Sul - UFMS, Av. Costa e Silva, s.n. Centro universitário SENAI-CIMATEC, Av. Orlando Gomes, 1845, Piatã Department of General and Inorganic Chemistry Institute of Chemistry São Paulo State University-Unesp, R. Prof. Francisco Degni 55, Quitandinha

A SiO₂-SO₃H amorphous catalyst containing a small surface area of 115.0 m²g