التفاصيل البيبلوغرافية
| العنوان: |
Fundamental studies on natural deep eutectic solvents: physico-chemical, thermal and rheological properties |
| المؤلفون: |
Aroso, Ivo Manuel Ascensão, Craveiro, Rita, Dionisio, Madalena, Barreiros, Susana, Reis, R. L., Paiva, Alexandre, Duarte, Ana Rita C. |
| المساهمون: |
Universidade do Minho |
| سنة النشر: |
2015 |
| مصطلحات موضوعية: |
Deep Eutectic Solvents, Properties |
| الوصف: |
When combined at particular molar fractions, sugars, aminoacids or organic acids a present a high melting point depression, becoming liquids at room temperature. These are called Natural Deep Eutectic Solvents – NADES and are envisaged to play a major role on the chemical engineering processes of the future. Nonetheless, there is a significant lack of knowledge of its fundamental and basic properties, which is hindering their industrial applications. For this reason it is important to extend the knowledge on these systems, boosting their application development [1]. In this work, we have developed and characterized NADES based on choline chloride, organic acids, amino acids and sugars. Their density, thermal behavior, conductivity and polarity were assessed for different compositions. The conductivity was measured from 0 to 40 °C and the temperature effect was well described by the Vogel-Fulcher-Tammann equation. The morphological characterization of the crystallizable materials was done by polarized optical microscopy that provided also evidence of homogeneity/phase separation. Additionally, the rheological and thermodynamic properties of the NADES and the effect of water content were also studied. The results show these systems have Newtonian behavior and present significant viscosity decrease with temperature and water content, due to increase on the molecular mobility. The anhydrous systems present viscosities that range from higher than 1000Pa.s at 20°C to less than 1Pa.s at 70°C. DSC characterization confirms that for water content as high as 1:1:1 molar ratio, the mixture retains its single phase behavior. The results obtained demonstrate that the NADES properties can be finely tunned by careful selection of its constituents. NADES present the necessary properties for use as extraction solvents. They can be prepared from inexpensive raw materials and tailored for the selective extraction of target molecules. The data produced in this work is hereafter importance for the selection of the most promising candidates avoiding a time consuming and expensive trial and error phase providing also data for the development of models able to predict their properties and the mechanisms that allow the formation of the deep eutectic mixtures. |
| الوصف (مترجم): |
Rita Craveiro and Alexandre Paiva are grateful for financial support from Fundação para a Ciência e a Tecnologia (FCT) through the grants PTDC/EQUEPR/12191/2010/ENIGMA and SFRH/BPD/44946/2008. The research leading to these results has received funding from through the projects ENIGMA - PTDC/EQU-EPR/121491/2010, PTDC/QUI-QUI/119210/2010, PTDC/EQUEQU/122106/2010, PEst-C/EQB/LA0006/2013 from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° REGPOT-CT2012-316331-POLARIS and from Project “Novel smart and biomimetic materials for innovative regenerative medicine approaches (Ref.: RL1 - ABMR - NORTE-01-0124-FEDER-000016)” co-financed by North Portugal Regional Operational Programme (ON.2 – O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF). |
| وصف الملف: |
application/pdf |
| اللغة: |
English |
| العلاقة: |
Aroso I. M., Craveiro R., Dionisio M., Barreiros S., Reis R. L., Paiva A., Duarte A. R. C. Fundamental studies on natural deep eutectic sol-vents: physico-chemical, thermal and rheological properties, NWBC 2015 - The 6th Nordic Wood Biorefinery Conference, 2015 |
| الإتاحة: |
http://hdl.handle.net/1822/40945Test |
| حقوق: |
open access |
| رقم الانضمام: |
rcaap.com.repositorium.repositorium.sdum.uminho.pt.1822.40945 |
| قاعدة البيانات: |
RCAAP |
