Electrodeposition of Cu onto Au(111) from Deep Eutectic Solvents: Molar Ratio of Salt and Hydrogen Bond Donor

2021 ◽  
Author(s):  
Tanja Geng ◽  
Sven J. Zeller ◽  
Ludwig A. Kibler ◽  
Maximilian Urs Ceblin ◽  
Timo Jacob
Keyword(s):  
Hydrogen Bond ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Hydrogen Bond Donor

Deacidification of Crude Rice Bran Oil (CRBO) to Remove FFA and Preserve γ-Oryzanol Using Deep Eutectic Solvents (DES)

2019 ◽  
Vol 964 ◽  
pp. 109-114 ◽  
Author(s):  
Siti Zullaikah ◽  
Nizar Dwi Wibowo ◽  
I Made Gede Eris Dwi Wahyudi ◽  
M. Rachimoellah
Keyword(s):  
Hydrogen Bond ◽  
Rice Bran ◽  
Rice Bran Oil ◽  
Choline Chloride ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Extraction Temperature ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Acceptor ◽  
C 50

High content of free fatty acids (FFA) in crude rice bran oil (CRBO) needs to be separated through deacidification. Generally, deacidification process that is widely used are chemical and physical processes which causes the loss of bioactive compounds (γ-oryzanol) and un-environmentally friendly. The liquid-liquid extraction (LLE) using deep eutectic solvents (DES) to remove FFA and preserve g-oryzanol would be implemented in this study. DES with different hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA) with certain molar ratio such as Choline Chloride (ChCl)-Ethylene glycol 1:2 (DES I), ChCl-Glycerol 1:1 (DES II), ChCl-Urea 1:2 (DES III), ChCl-Oxalic acid 1:2 (DES IV), and Betaine Monohydrate-Glycerol 1:8 (NADES) were used as solvent to extract FFA from dewaxed/degummed RBO (DDRBO) for certain extraction time (30, 60, 120, 180, and 240 min) and extraction temperature (30°C, 40°C, 50°C, 60°C, and 70°C) under stirring (200 rpm). Deacidification using DES I for 240 min. and temperature of 50 °C was the optimum solvent to remove FFA (19.03 ± 2.33 %) and preserve g-oryzanol (recovery of g-oryzanol was 51.30 ± 1.77 %). The results also revealed that the longer time of extraction would be increased removal of FFA and decreased recovery of g-oryzanol. The higher temperature of extraction would be increased removal of FFA. In this work, temperature of 50 °C was the best extraction temperature of FFA since DES has highest solubility at this temperature.

scholarly journals Effect of Four Novel Bio-Based DES (Deep Eutectic Solvents) on Hardwood Fractionation

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2157 ◽  
Author(s):  
Paulo Torres ◽  
Mercè Balcells ◽  
Enrique Cequier ◽  
Ramon Canela-Garayoa
Keyword(s):  
Hydrogen Bond ◽  
Lactic Acid ◽  
Scale Up ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Olive Pomace ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Acceptor ◽  
Raw Glycerol ◽  
Lignin Recovery

Using the basic principle of construction between a hydrogen bond acceptor (HBA) and a hydrogen bond donor (HBD), four bio-based deep eutectic solvents (DESs) were prepared in a 1:2 molar ratio of HBA:HBD. 2,3-Dihydroxypropyl-1-triethylammonium chloride ([C9H22N+O2]Cl−) was synthesized from raw glycerol and used as an HBA. Lactic acid, urea, pure glycerol, and ethylene glycol were selected as HBD. Attempts to prepare DESs, using citric acid and benzoic acid as HBDs, were unsuccessful. All these DESs were characterized using FTIR and NMR techniques. Besides, physicochemical parameters such as pH, viscosity, density, and melting point were determined. The behavior of these DES to fractionate olive pomace was studied. Lignin recovery yields spanned between 27% and 39% (w/w) of the available lignin in olive pomace. The best DES, in terms of lignin yield ([C9H22N+O2]Cl− -lactic acid), was selected to perform a scale-up lignin extraction using 40 g of olive pomace. Lignin recovery on the multigram scale was similar to the mg scale (38% w/w). Similarly, for the holocellulose-rich fractions, recovery yields were 34% and 45% for mg and multi-gram scale, respectively. Finally, this DES was used to fractionate four fruit pruning samples. These results show that our novel DESs are alternative approaches to the ionic liquid:triethylammonium hydrogen sulfate and the widely used DES: choline chloride:lactic acid (1:10 molar ratio) for biomass processing.

scholarly journals pH, Viscosity of Hydrophobic Based Natural Deep Eutectic Solvents and the Effect of Curcumin Solubility in it

2021 ◽  
Vol 11 (6) ◽  
pp. 14620-14633
Keyword(s):  
Hydrogen Bond ◽  
Room Temperature ◽  
Water Solubility ◽  
Deep Eutectic Solvent ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Hydrogen Bond Donor ◽  
Hydrogen Bond Acceptor ◽  
Natural Deep Eutectic Solvents ◽  
Self Association

Turmeric contains curcumin as one of the active constituents, which gives yellow color and possesses lots of pharmacological actions. Even though curcumin has lots of pharmacological actions till now, it has not been approved as a medicine due to its low water solubility, permeability, and poor bioavailability. Deep eutectic solvent (DES) can be prepared by simply mixing two or more solid components, [among the two one is hydrogen bond donor (HBD) and another is hydrogen bond acceptor (HBA)] at a definite molar ratio where the solid components by self-association converted into a liquid at room temperature (RT). Natural deep eutectic solvents (NADES) are a specific subgroup of DES containing primary plant-based metabolites such as organic acids, alcohols, amino acids, or sugars. In this work, natural hydrophobic DESs were prepared with Camphor, Menthol, and Thymol. This was prepared from different ratios of Menthol:Thymol 1:1 to 1:5 and 1:1 to 5:1 (MT-DES); Camphor:Thymol 1:1 to 1:5 and 1:1 to 5:1 (CT-NADES); Camphor:Menthol 1:1 to 1:5 and 1:1 to 2:1 (CM-NADES). The pH and viscosity of prepared DESs were determined with the help of a digital pH meter and Brookfield viscometer. The solubility of curcumin in different NADESs was determined at room temperature (RT) to higher temperatures. The formation of different clear DES was obtained with slight heat. There was no difference in pH for the NADESs prepared without and with heat. Regarding the viscosity CM-DES (1:1) showed less viscosity when compared to other NADESs. The solubility of curcumin was found to be nearly double when it was dissolved in NADES for 1 hr at 35-40°C compared to 48 h stirring at 500 rotations per minute (rpm) at RT. Among different NADESs, curcumin solubility was found to be more in CM (1:1) ratio when compared to other NADESs.

scholarly journals Solubility of Carbon Dioxide in Deep Eutectic Solvents Based on 3-Amino-1-Propanol and Tetraalkylammonium Salts at Low Pressure

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 594
Author(s):  
Iwona Cichowska-Kopczyńska ◽  
Dorota Warmińska ◽  
Bartosz Nowosielski
Keyword(s):  
Hydrogen Bond ◽  
Alkyl Chain ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Co2 Uptake ◽  
Hydrogen Bond Donor ◽  
Molar Ratios ◽  
The Fourier Transform ◽  
Low Pressures ◽  
Anion Type

Deep eutectic solvents (DESs) became an object of a great interest as an alternative to ionic liquids (ILs) and commonly used in CO2 capture amine solutions. In the present study, five different DESs based on 3-amino-1-propanol as physical-chemical CO2 absorbents were used. The composition was chosen in order to estimate the effects of hydrogen bond acceptor:hydrogen bond donor (HBA:HBD) molar ratio, anion type and length of alkyl chain of composing salt. The Fourier Transform Infrared (FTIR) spectroscopy was used to confirm chemical reaction. The solubility of CO2 was measured at low pressures up to 170 kPa at the temperature range of 293–318 K. Viscosity, polarity and Kamlet–Taft parameters were determined in order to estimate the dependences of the parameters and the CO2 capacity. CO2 uptake was observed to improve with decreasing molar ratio of hydrogen bond donor. Comparing the CO2 capacity of [TBAC]-based DESs, at the approximate pressure of 50 kPa, it was observed that the capacity increased in the following order of molar ratios—1:8 < 1:6 < 1:4 and a decrease in molar ratio from 1:8 to 1:4 resulted in about a 100% increase of capacity. Compared to [TBAC][AP] DESs, the [TEAC][AP] 1:4 and [TBAB][AP] 1:4 exhibited higher CO2 uptake, though the best results were obtained for [TBAB][AP].

Deep eutectic solvents : investigation of solvent structure and its applications

2017 ◽  
Author(s):  
◽  
Durgest Vinod Wagle
Keyword(s):  
Hydrogen Bond ◽  
Charge Transfer ◽  
Hydrogen Bonds ◽  
Quantum Chemical ◽  
Choline Chloride ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Hydrogen Bond Donor ◽  
Diffusion Dynamics ◽  
Pi Interactions

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Deep eutectic solvents (DESs) represent an alternative class of ionic fluids closely resembling room-temperature ionic liquids (RTILs), they are distinguished by the fact that they also contain an organic molecular component (typically, a hydrogen-bond donor like a urea, amide, acid, or polyol), frequently as the predominant constituent. DESs possess several advantages over RTILs while being less expensive, synthetically accessible, nontoxic, and biodegradable. In this work we have probed into liquid structure of DES using quantum chemical calculations and neutron scattering experiments to elucidate the molecular interactions, charge transfer interactions, thermodynamics and mass transport associated with these systems. The DESs studied comprise 1:2 choline chloride/urea (reline), 1:2 choline chloride/ethylene glycol (ethaline), 1:2 molar ratio of choline chloride to glycerol (glyceline) and 1:1 choline chloride/malonic acid (maloline). The DESs were found to be stabilized by both conventional hydrogen bonds and C-H...[pi] interactions with significant charge transfer from choline and chloride to the hydrogen-bond donors, further confirmed by density of states analysis. Consequently, it was found that the sum of the bond orders of various choline-C1[minus] interactions in the DESs correlates directly with the melting temperatures of the DESs. From macroscopic measurements of glyceline, it was observed that the long-range translational diffusion of the larger cation (choline) is slower compared to the smaller glycerol molecule. However, the diffusion dynamics analyzed on the subnanometer length scale revealed that the displacements associated with the localized diffusive motions are actually larger for choline. This is due to ability of glycerol to form stronger hydrogen bonds with chloride anions compared to choline cation. Quantum chemical simulations performed on ASCs paired reline and ethaline DES systems revealed that ASCs interacted with the choline and HBD components of DESs through multiple unconventional non-covalent interactions i.e., CH...[pi], C=O...[pie], O-H...[pi] and N-H...[pi] interactions. Oxidation of ASCs improved interaction with DES components due enhanced ability to form multiple hydrogen bonds. ASCs exhibited significant improvement in change free energy of solvation upon oxidation indicating that oxidation could aid in enhancing selective extraction of oxidized ASCs from liquid fuel using DES.

Role of the hydrogen bond donor component for a proper development of novel hydrophobic deep eutectic solvents

2019 ◽  
Vol 281 ◽  
pp. 423-430 ◽  
Author(s):  
Matteo Tiecco ◽  
Federico Cappellini ◽  
Francesco Nicoletti ◽  
Tiziana Del Giacco ◽  
Raimondo Germani ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Deep Eutectic Solvents ◽  
Hydrogen Bond Donor

scholarly journals Study on the Dissolution Mechanism of Cellulose by ChCl-Based Deep Eutectic Solvents

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 278 ◽  
Author(s):  
Heng Zhang ◽  
Jinyan Lang ◽  
Ping Lan ◽  
Hongyan Yang ◽  
Junliang Lu ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Oxalic Acid ◽  
Deep Eutectic Solvents ◽  
Solvent System ◽  
Hydroxyl Group ◽  
Regenerated Cellulose ◽  
Dissolution Mechanism ◽  
Hydroxyl Groups ◽  
Type I ◽  
Hydrogen Bond Donor

Four deep eutectic solvents (DESs), namely, glycerol/chlorocholine (glycerol/ChCl), urea/ChCl, citric acid/ChCl, and oxalic acid/ChCl, were synthesized and their performance in the dissolution of cellulose was studied. The results showed that the melting point of the DESs varied with the proportion of the hydrogen bond donor material. The viscosity of the DESs changed considerably with the change in temperature; as the temperature increased, the viscosity decreased and the electrical conductivity increased. Oxalic acid/ChCl exhibited the best dissolution effects on cellulose. The microscopic morphology of cellulose was observed with a microscope. The solvent system effectively dissolved the cellulose, and the dissolution method of the oxalic acid/ChCl solvent on cellulose was preliminarily analyzed. The ChCl solvent formed new hydrogen bonds with the hydroxyl groups of the cellulose through its oxygen atom in the hydroxyl group and its nitrogen atom in the amino group. That is to say, after the deep eutectic melt formed an internal hydrogen bond, a large number of remaining ions formed a hydrogen bond with the hydroxyl groups of the cellulose, resulting in a great dissolution of the cellulose. Although the cellulose and regenerated cellulose had similar structures, the crystal form of cellulose changed from type I to type II.

scholarly journals Facilely reducing recalcitrance of lignocellulosic biomass by a newly developed ethylamine-based deep eutectic solvent for biobutanol fermentation

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Guochao Xu ◽  
Hao Li ◽  
Wanru Xing ◽  
Lei Gong ◽  
Jinjun Dong ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Lactic Acid ◽  
Lignocellulosic Biomass ◽  
Fossil Fuels ◽  
Deep Eutectic Solvent ◽  
Deep Eutectic Solvents ◽  
Specific Yield ◽  
Green Solvents ◽  
Hydrogen Bond Donor ◽  
Total Sugars

Abstract Background Biobutanol is promising and renewable alternative to traditional fossil fuels and could be produced by Clostridium species from lignocellulosic biomass. However, biomass is recalcitrant to be hydrolyzed into fermentable sugars attributed to the densely packed structure by layers of lignin. Development of pretreatment reagents and processes for increasing surface area, removing hemicellulose and lignin, and enhancing the relative content of cellulose is currently an area of great interest. Deep eutectic solvents (DESs), a new class of green solvents, are effective in the pretreatment of lignocellulosic biomass. However, it remains challenging to achieve high titers of total sugars and usually requires combinatorial pretreatment with other reagents. In this study, we aim to develop novel DESs with high application potential in biomass pretreatment and high biocompatibility for biobutanol fermentation. Results Several DESs with betaine chloride and ethylamine chloride (EaCl) as hydrogen bond acceptors were synthesized. Among them, EaCl:LAC with lactic acid as hydrogen bond donor displayed the best performance in the pretreatment of corncob. Only by single pretreatment with EaCl:LAC, total sugars as high as 53.5 g L−1 could be reached. Consecutive batches for pretreatment of corncob were performed using gradiently decreased cellulase by 5 FPU g−1. At the end of the sixth batch, the concentration and specific yield of total sugars were 58.8 g L−1 and 706 g kg−1 pretreated corncob, saving a total of 50% cellulase. Utilizing hydrolysate as carbon source, butanol titer of 10.4 g L−1 was achieved with butanol yield of 137 g kg−1 pretreated corncob by Clostridium saccharobutylicum DSM13864. Conclusions Ethylamine and lactic acid-based deep eutectic solvent is promising in pretreatment of corncob with high total sugar concentrations and compatible for biobutanol fermentation. This study provides an efficient pretreatment reagent for facilely reducing recalcitrance of lignocellulosic materials and a promising process for biobutanol fermentation from renewable biomass.

scholarly journals Tetraethylammonium Acetate and Tetraethylammonium Bromide-Based Deep Eutectic Solvents as Thermodynamic CO2 Gas Hydrate Inhibitors

2020 ◽  
Vol 10 (19) ◽  
pp. 6794
Author(s):  
Vinayagam Sivabalan ◽  
Nurasyikin Hasnor ◽  
Bhajan Lal ◽  
Zamzila Kassim ◽  
Abdulhalim Shah Maulud
Keyword(s):  
Hydrogen Bond ◽  
Ethylene Glycol ◽  
Gas Hydrate ◽  
Deep Eutectic Solvents ◽  
Molar Ratio ◽  
Tetraethylammonium Bromide ◽  
Hydrate Dissociation ◽  
Co2 Gas ◽  
Vapor Equilibrium ◽  
Liquid Vapor

The thermodynamic gas hydrate suppression behavior of four Deep Eutectic Solvents (DESs) was evaluated in this paper. The mixtures of Hydrogen Bond Acceptors (HBA), Tetraethylammonium Acetate (TEAAC), and Tetraethylammonium Bromide (TEAB) with Hydrogen Bond Donors (HBD), Mono-Ethylene Glycol (MEG), and Glycerol were used to make the DES. The DESs were made at a 1:7 molar ratio for the combinations of TEAAC:MEG, TEAAC:Glycerol, TEAB:MEG, and TEAB:Glycerol. The Hydrate Liquid-Vapor Equilibrium (HLVE) data for CO2 were evaluated through the T-cycle method at different temperature (273.15–283.15 K) and pressure (2–4 MPa) conditions in the presence and absence of 5 wt % aqueous DES solutions. The inhibition effects showed by the DESs, including average suppression temperature (ΔŦ) and gas hydrate dissociation enthalpies (ΔHdiss), were also calculated. The average suppression temperature values of the DESs ranged between 0.4 and 2.4, with the highest inhibition to lowest inhibition order being TEAB:Glycerol > TEAB:MEG > TEAAC:Glycerol > TEAAC:MEG. A comparison of the DES with conventional Thermodynamic Hydrate Inhibitors (THIs) showed that studied Deep Eutectic Solvents had better gas hydrate inhibition. The results proved that DES has the potential to be one of the promising alternatives in gas hydrate inhibition.

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