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1.
Environ Sci Pollut Res Int ; 30(10): 24890-24898, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35102506

RESUMO

Levulinic acid is a carboxylic acid present in industrial downstream. It is an important chemical and can be transformed into various important chemicals such as 1,4-pentanediol, aminolevulinic acid, succinic acid, gamma valarolactone, hydoxyvaleric acid, and diphenolic acid. It is considered one of the top ten most important building block chemicals and bio-derived acids. Levulinic acid can be directly produced using biomass, chemical synthesis, and fermentation processes at industrial and laboratory scales. The biomass process produces the char, whereas the fermentation process generates waste during the production of levulinic acid, leading to an increase in the production cost and waste streams. The separation of levulinic acid from the waste is expensive and challenging. In the present study, reactive extraction was employed using trioctylamine in i-octanol for the separation of levulinic acid. The experimental results were expressed in terms of performance parameters like distribution coefficient (0.099-6.14), extraction efficiency (9-86%), loading ratio (0.09-0.7), and equilibrium complexation constant (11.34-1.05). The mass action law model was also applied and found the predicted values were in close agreement with the experimental results. The mixer settler extraction in series was used to achieve more than 98% separations of acid. Furthermore, the conceptual approach for separation of levulinic acid using a mixer settler reactor scheme was discussed and presented various design parameters including extraction efficiency, diffusion coefficient, equilibrium complexation constant, and loading ratio. The study is helpful in recovering the valuable chemicals present in industrial downstream and reducing their environmental impacts if any.


Assuntos
Ácidos Levulínicos , Fermentação
2.
Environ Sci Pollut Res Int ; 29(57): 86468-86484, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35710969

RESUMO

This paper reviews the improvement in the field of catalytic hydrogenation of 2-ethylanthraquinone to 2-ethylanthrahydroquinone for the successful production of hydrogen peroxide. Hydrogen peroxide is being used in almost all industrial areas, particularly in the chemical industry and in environmental protection, as the most promising oxidant for cleaner and environmentally safer processes. A variety of hydrogenation catalysts have been introduced for hydrogenation of 2-ethylanthraquinone in the production of hydrogen peroxide via anthraquinone (AQ) process. The aim of the present study is to describe the catalysts used in the hydrogenation of 2-ethylanthraquinone and the reaction mechanism involved with different catalytic systems. The hydrogenation of 2-ethylanthraquinone using metals, alloy, bimetallic composite, and supported metal catalyst with the structural modifications has been incorporated for the production of hydrogen peroxide. The comprehensive comparison reveals that the supported metal catalysts required lesser catalyst amount, produced lower AQ decay, and provided higher catalyst activity and selectivity. Furthermore, the replacement of conventional catalysts by metal and metal alloy-supported catalyst rises as a hydrogenation trend, enhancing by several times the catalytic performance.


Assuntos
Peróxido de Hidrogênio , Metais , Catálise , Hidrogenação , Metais/química , Antraquinonas , Ligas
3.
Environ Sci Pollut Res Int ; 23(10): 9284-94, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26139406

RESUMO

1-Butyl-3-methylimidazolium thiocyanate [BMIM]SCN has been presented on extractive desulfurization of liquid fuel. The FTIR, (1)H-NMR, and C-NMR have been discussed for the molecular confirmation of synthesized [BMIM]SCN. Further, thermal, conductivity, moisture content, viscosity, and solubility analyses of [BMIM]SCN were carried out. The effects of time, temperature, sulfur compounds, ultrasonication, and recycling of [BMIM]SCN on removal of dibenzothiophene from liquid fuel were also investigated. In extractive desulfurization, removal of dibenzothiophene in n-dodecane was 86.5 % for mass ratio of 1:1 in 30 min at 30 °C under the mild process conditions. [BMIM]SCN could be reused five times without a significant decrease in activity. Also, in the desulfurization of real fuels, multistage extraction was examined. The data and results provided in the present paper explore the significant insights of imidazolium-based ionic liquids as novel extractant for extractive desulfurization of liquid fuels.


Assuntos
Imidazóis/síntese química , Enxofre/química , Tiocianatos/síntese química , Animais , Imidazóis/química , Líquidos Iônicos/química , Reciclagem , Solubilidade , Compostos de Enxofre/química , Temperatura , Tiocianatos/química , Tiofenos/química , Viscosidade
4.
ScientificWorldJournal ; 2013: 395274, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24307868

RESUMO

The possible application of imidazolium ionic liquids as energy-efficient green material for extractive deep desulfurization of liquid fuel has been investigated. 1-Butyl-3-methylimidazolium chloride [BMIM]Cl was synthesized by nucleophilic substitution reaction of n-methylimidazolium and 1-chlorobutane. Molecular structures of the ILs were confirmed by FTIR, (1)H-NMR, and (13)C-NMR. The thermal properties, conductivity, solubility, water content and viscosity analysis of [BMIM]Cl were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of IL without regeneration on dibenzothiophene removal of liquid fuel were presented. In the extractive desulfurization process, the removal of dibenzothiophene in n-dodecane using [BMIM]Cl was 81% with mass ratio of 1 : 1, in 30 min at 30°C under the mild reaction conditions. Also, desulfurization of real fuels with IL and multistage extraction were studied. The results of this work might offer significant insights in the perceptive use of imidazoled ILs as energy-efficient green material for extractive deep desulfurization of liquid fuels as it can be reused without regeneration with considerable extraction efficiency.


Assuntos
Engenharia Química/métodos , Óleos Combustíveis/análise , Química Verde/métodos , Imidazóis/química , Imidazóis/síntese química , Compostos de Enxofre/química , Butanos/química , Condutividade Elétrica , Espectroscopia de Ressonância Magnética , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Viscosidade
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