Tunable Hydrophobic Eutectic Solvents Based on Terpenes and Monocarboxylic Acids

Autor(es)

Martins, Monia A. R. ^{[1, 2, 3, 4]} ; Crespo, Emanuel A. ^{[2, 5]} ; Pontes, Paula V. A. ^[1] ; Silva, Liliana P. ^[2] ; Buelow, Mark ^[5] ; Maximo, Guilherme J. ^[1] ; Batista, Eduardo A. C. ^[1] ; Held, Christoph ^[5] ; Pinho, Simao P. ^{[3, 4]} ; Coutinho, Joao A. P. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Fac Food Engn, BR-13083862 Campinas, SP - Brazil

^[2] Univ Aveiro, Dept Chem, Aveiro Inst Mat, CICECO, P-3810193 Aveiro - Portugal

^[3] Polytech Inst Braganca, Dept Chem & Biol Technol, Associate Lab LSRE LCM, P-5300253 Braganca - Portugal

^[4] Polytech Inst Braganca, Mt Res Ctr CIMO, P-5301855 Braganca - Portugal

^[5] TU Dortmund, Dept Biochem & Chem Engn, Lab Thermodynam, D-44227 Dortmund - Germany

• Tipo de documento: Artigo Científico
• Fonte: ACS SUSTAINABLE CHEMISTRY & ENGINEERING; v. 6, n. 7, p. 8836-8846, JUL 2018.
• Citações Web of Science: 27

Resumo

Recently, some works claim that hydrophobic deep eutectic solvents could be prepared based on menthol and monocarboxylic acids. Despite of some promising potential applications, these systems were poorly understood, and this work addresses this issue. Here, the characterization of eutectic solvents composed of the terpenes thymol or L(-)-menthol and monocarboxylic acids is studied aiming the design of these solvents. Their solid-liquid phase diagrams were measured by differential scanning calorimetry in the whole composition range, showing that a broader composition range, and not only fixed stoichiometric proportions, can be used as solvents at low temperatures. Additionally, solvent densities and viscosities close to the eutectic compositions were measured, showing low viscosity and lower density than water. The solvatochromic parameters at the eutectic composition were also investigated aiming at better understanding their polarity. The high acidity is mainly provided by the presence of thymol in the mixture, while L(-)-menthol plays the major role on the hydrogen-bond basicity. The measured mutual solubilities with water attest to the hydrophobic character of the mixtures investigated. The experimental solid-liquid phase diagrams were described using the PC-SAFT equation of state that is shown to accurately describe the experimental data and quantify the small deviations from ideality. (AU)

• Processo FAPESP: 14/21252-0 - Equilíbrio e processos de produção de biocombustíveis e bioprodutos
• Beneficiário: Antonio José de Almeida Meirelles
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/08566-1 - Termodinâmica do equilíbrio de fases para o melhoramento das propriedades físicas de bioprodutos alimentícios e sua predição em processos industriais e digestivos
• Beneficiário: Guilherme José Maximo
• Linha de fomento: Auxílio à Pesquisa - Regular