resumo
A series of novel analogues of glycine-betaine ionic liquids (AGB-ILs), viz. 1-(4-ethoxy-4-oxobutyl)-1-methylpyrrolidin-1-ium, N,N,N-tri(n-butyl)(4-ethoxy-4-oxobutyl)-1-phosphonium and N,N,N-tri-alkyl(4-ethoxy-4-oxobutyl)-1-aminium cations with ethyl, n-propyl and n-butyl alkyl chains, combined with the bromide anion, have been synthesized and characterized. Their synthesis and characterization by spectroscopic methods and elemental analysis is here reported. These ILs were further characterized in what concerns their thermal properties and ecotoxicity against Allvibrio fischeri, and compared with degrees the commercial tetra(n-butyl)ammonium and tetra(n-butyl)phosphonium bromide. The novel AGB-ILs described in this work have low melting points, below 100 degrees C, display high degradation temperatures (180-310 degrees C), and low toxicity as shown by being harmless or practically harmless towards the marine bacteria Allvibrio fischeri. Finally, the ability of the synthesized AGB-ILs to form aqueous biphasic systems with potassium citrate/citric acid (at pH 7) was evaluated, and the respective ternary phase diagrams were determined. It is shown that the increase of the cation alkyl chain length facilitates the creation of ABS, and that phosphonium-based ILs present a slightly better separation performance in presence of aqueous solutions of the citrate-based salt. (C) 2019 Elsevier B.V. All rights reserved.
palavras-chave
ENHANCED EXTRACTION; CATION; PHOSPHONIUM; TOXICITY; PRETREATMENT; SOLVENTS; RECOVERY; REMOVAL; BIOMASS; STRESS
categoria
Thermodynamics; Chemistry; Engineering
autores
Pereira, MM; Pedro, SN; Gomes, J; Sintra, TE; Ventura, SPM; Coutinho, JAP; Freire, MG; Mohamadou, A
nossos autores
Mara Guadalupe Freire Martins
Investigador Coordenador
Matheus M. Pereira
Investigador
Sónia Isabel Neto Pedro
Estudante de doutoramento
Sónia Patrícia Marques Ventura
Professor Auxiliar
Tânia Ereira Sintra
Bolseiro de pós-DoutoramentoGrupos
G4 - Materiais Renováveis e Economia Circular
G5 - Materiais Biomiméticos, Biológicos e Vivos
G6 - Materiais Virtuais e Inteligência Artificial
Projectos
Igy Technology: A Purication Platform using Ionic-Liquid-Based Aqueous Biphasic Systems (IGYPURTECH)
agradecimentos
This work was developed within the scope of the project FCT Ref. UlD/CTM/50011/2019, financed by national funds through the FCT/MCTES. M. M. Pereira acknowledges the PhD grant (2740-13-3) and financial support from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior Capes and the Short Term Scientific Mission grant COST-STSM-ECOST-STSM-CM1206-011015-066583. M. G. Freire acknowledges the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC Grant 337753. We acknowledge D. Harakat for the ESI-MS measurements.