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1.
Ciênc. rural (Online) ; 52(2): e20210068, 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1286060

RESUMO

This research valorized Pachira aquatica Aubl.'s fruit shells (PAS) through its energetic characterization and flash pyrolysis for biofuels or chemicals production. The characterization was performed through proximate and ultimate analysis, bulk density, higher heating value (HHV), hemicellulose, cellulose and lignin content, thermogravimetric analysis and absorption spectra in the infrared region obtained by Fourier-transform infrared spectroscopy technique (FTIR). The analytical flash pyrolysis was performed at 500°C in a Py-5200 HP-R coupled to a gas chromatograph (Py-GC/MS). The PAS biomass presents potential for thermochemical energy conversion processes due to its low moisture and ash content, 76.90% of volatile matter, bulk density of 252.6 kg/m3 and HHV of 16.24 MJ/kg. Flash pyrolysis products are mostly phenols or light organic acids derived from the decomposition of polysaccharides. Results confirmed the potential of PAS to produce bio-phenolics, such as 4-methoxyphenol which is an important active ingredient for skin depigmentation used in drugs and cosmetics, and as phenolic extract that can be used as a precursor to resins, applications that convert this forest waste into bio products for industry into a green circular economy.


Este trabalho teve como objetivo a valorização das cascas dos frutos da Pachira aquatica Aubl. (PAC) através da sua caracterização energética e pirólise flash para produção de biocombustíveis ou produtos químicos. A caracterização foi realizada através de análises imediata e final, densidade aparente, poder calorífico superior (PCS), conteúdos de hemicelulose, celulose e lignina, análise termogravimétrica e espectros de absorção na região do infravermelho obtidos pela técnica de espectroscopia no infravermelho com transformada de Fourier (FTIR). A pirólise flash analítica foi realizada a 500 °C em equipamento Py-5200 HP-R acoplado a um cromatógrafo à gás (Py-GC/MS). A biomassa das PAC apresenta potencial para processos de conversão termoquímica de energia devido ao seu baixo teor de umidade e cinzas, além de 76,90% de materiais voláteis, densidade aparente de 252,6 kg/m3 e PCS igual a 16,24 MJ / kg. Os produtos da pirólise rápida são principalmente fenóis ou ácidos orgânicos leves derivados da decomposição de polissacarídeos. Os resultados confirmam o potencial das PAC para produzir bio-fenólicos, como o 4-metoxifenol que é um importante ingrediente ativo para despigmentação da pele usado em medicamentos e cosméticos, e como extrato fenólico que pode ser usado como precursor de resinas. Estas aplicações convertem esses resíduos florestais em produtos biológicos para a indústria em uma economia circular verde.


Assuntos
Pirólise , Biomassa , Bombacaceae , Frutas/química , Lignina , Polissacarídeos , Biocombustíveis
2.
Sci Rep ; 11(1): 16087, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373480

RESUMO

This study aims to analyze the products of the catalytic pyrolysis of naturally colored cotton residues, type BRS (seeds from Brazil), called BRS-Verde, BRS-Rubi, BRS-Topázio and BRS-Jade. The energy characterization of biomass was evaluated through ultimate and proximate analysis, higher heating value, cellulose, hemicellulose and lignin content, thermogravimetric analysis and apparent density. Analytical pyrolysis was performed at 500 °C in an analytical pyrolyzer from CDS Analytical connected to a gas chromatograph coupled to the mass spectrometer (GC/MS). The pyrolysis vapors were reformed at 300 and 500 °C through thermal and catalytic cracking with zeolites (ZSM-5 and HZSM-5). It has been noticed that pyrolysis vapor reforming at 500 °C promoted partial deoxygenation and cracking reactions, while the catalytic reforming showed better results for the product deoxygenation. The catalyst reforming of pyrolysis products, especially using HZSM-5 at 500 °C, promoted the formation of monoaromatics such as benzene, toluene, xylene and styrene, which are important precursors of polymers, solvents and biofuels. The main influence on the yields of these aromatic products is due to the catalytic activity of ZSM-5 favored by increased temperature that promotes cracking reactions due expanded zeolites channels.

3.
Environ Sci Pollut Res Int ; 26(14): 14259-14265, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864027

RESUMO

Cotton crops generate millions of tons of lignocellulosic waste in Brazil that could be used in energy generation; however, the main destination of this raw material is soil incorporation. The aim of this work was to perform an energetic characterization and evaluation of briquettes produced from different agricultural waste of naturally colored cotton for power generation. The cultivars Brasil Sementes (BRS) Jade and Topazio were studied, with white cotton (BRS 286) as standard for comparison purposes. Two different parts of each species, stalk and cotton shell, were analyzed by bulk density, proximate analysis, higher heating value, cellulose, hemicellulose, protein, fat and lignin content, thermogravimetric analysis, and briquette mechanical strength. The results of the energetic characterization indicated a higher energetic potential of the colored species when compared with the white cotton, especially because of the volatile matter content, fixed carbon, and higher heating value. The briquette mechanical strength was higher in the samples formulated by a mixture of stalk and shell. Finally, it was concluded that the waste from colored cotton cultivars, Jade and Topazio, is capable to generate briquettes with good mechanical and physico-chemical characteristics, especially those formed by the mixture of stalk and shell.


Assuntos
Fontes Geradoras de Energia , Gossypium/química , Resíduos/análise , Biomassa , Brasil , Celulose/análise , Gossypium/crescimento & desenvolvimento , Calefação , Lignina/análise , Proteínas de Plantas/análise
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