Could choline chloride-citric acid monohydrate molar ratio in deep eutectic solvent affect structural, functional and antioxidant properties of pectin?

Abstract Within the framework of green chemistry, catalysts should be met different criteria such as biodegradability, recyclability, flammability, non-toxicity and low price. Acidic deep eutectic solvent (DES) have been synthesized for this purpose, by mixing para-toluene sulfonic acid and choline chloride. The catalytic activity of DES was studied in the esterification of acrylic acid with n-butanol. The usage of DES as catalyst is simple, safe and cheap. The effects of temperature, catalyst loading, n-butanol/acrylic acid molar ratio on the conversion of acrylic acid were performed. The batch reactor experiments were carried out at temperatures of 338, 348, 358 and 368 K, molar ratio of butanol to acrylic acid of 1, 2,3 and catalyst loading of 10, 15, 20 and 90 g/L. 90.2% of acrylic acid conversion was achieved at a temperature of 358 K and catalyst loading of 20 g/L. Reusability of DES was investigated. Reusability and catalytic activity makes DES efficient as catalyst.

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The Anodic Behaviour of Bulk Copper in Ethaline and 1-Butyl-3-Methylimidazolium Chloride

Applied Sciences ◽

10.3390/app9204401 ◽

2019 ◽

Vol 9 (20) ◽

pp. 4401 ◽

Cited By ~ 4

Author(s):

Karim ◽

Aziz ◽

Brza ◽

Abdullah ◽

Kadir

Keyword(s):

Electrochemical Impedance ◽

Choline Chloride ◽

Metallic Copper ◽

Electrochemical Techniques ◽

Deep Eutectic Solvent ◽

Molar Ratio ◽

Interfacial Region ◽

Dissolution Mechanism ◽

Spectroscopic Techniques ◽

Electrochemical Dissolution

The anodic dissolution of bulk metallic copper was conducted in ionic liquids (ILs)—a deep eutectic solvent (DES) ((CH3)3NC2H4OH) comprised of a 1:2 molar ratio mixture of choline chloride Cl (ChCl), and ethylene glycol (EG)—and imidazolium-based ILs, such as C4mimCl, using electrochemical techniques, such as cyclic voltammetry, anodic linear sweep voltammetry, and chronopotentiometry.To investigate the electrochemical dissolution mechanism, electrochemical impedance spectroscopy (EIS) was used. In addition to spectroscopic techniques, for instance, UV-visible spectroscopy, microscopic techniques, such as atomic force microscopy (AFM), were used. The significant industrial importance of metallic copper has motivated several research groups to deal with such an invaluable metal. It was confirmed that the speciation of dissolved copper from the bulk phase at the interface region is [CuCl3]− and [CuCl4]2− in such chloride-rich media, and the EG determine the structure of the interfacial region in the electrochemical dissolution process. A super-saturated solution was produced at the electrode/solution interface and CuCl2 was deposited on the metal surface.

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Novel Deep Eutectic Solvent Based on Levulinic Acid and 1,4-Butanediol as an Extraction Media for Bioactive Alkaloid Rutaecarpine

Processes ◽

10.3390/pr7030171 ◽

2019 ◽

Vol 7 (3) ◽

pp. 171 ◽

Cited By ~ 4

Author(s):

Yue-Yue Si ◽

Shi-Wei Sun ◽

Kun Liu ◽

Yang Liu ◽

Hai-Lin Shi ◽

...

Keyword(s):

Levulinic Acid ◽

Extraction Efficiency ◽

Choline Chloride ◽

Extraction Procedure ◽

Deep Eutectic Solvent ◽

Supermolecular Structure ◽

Molar Ratio ◽

Resonance Spectroscopy ◽

Extraction Temperature ◽

Unripe Fruits

Deep eutectic solvents (DESs) are increasingly receiving interest as a new type of green and sustainable alternative to hazardous organic solvents. In this work, a novel DES based on levulinic acid (La) and 1,4-butanediol (Buta) as an extraction media was developed for extracting the bioactive alkaloid rutaecarpine from the unripe fruits of Tetradium ruticarpum. 24 different DESs consisting of choline chloride, betaine, sugar alcohols, organic acids, amides, and sugars were prepared and tailored to test their extraction efficiency. After initial screening, a hydrophilic DES composed of La and Buta with 1:0.5 molar ratio containing 25% water was tailored for the highest extraction efficiency, followed by the optimizations of molar ratio and water content. The interaction between the molecules of La-Buta DES was investigated by nuclear magnetic resonance spectroscopy in order to confirm its deep eutectic supermolecular structure feature. The extraction conditions were optimized by single-factor experiments, including extraction temperature, extraction time, and solid-liquid ratio. The developed La-Buta DES extraction procedure was successfully applied for the analysis of rutaecarpine in Chinese patent medicines containing the unripe fruits of T. ruticarpum. The excellent property of La-Buta DES indicated its potential as a promising green solvent instead of conventional organic solvent for the extraction of rutaecarpine from the unripe fruits of T. ruticarpum, and that it can used as a sustainable and safe extraction media for other applications.

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Study on the Effect of Deep Eutectic Solvent Liquid Phase Microextraction on Quality Standard, Antitussive, and Expectorant of Sangbaipi Decoction

Journal of Analytical Methods in Chemistry ◽

10.1155/2021/9999406 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Lijing Li ◽

Yuejie Wang ◽

Fangxin Liu ◽

Yang Xu ◽

Huiwei Bao

Keyword(s):

Liquid Phase ◽

Extraction Method ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Quality Standard ◽

Molar Ratio ◽

Phenol Red ◽

Liquid Ratio ◽

Liquid Phase Microextraction ◽

Low Efficiency

The SD was extracted with a new green eutectic solvent, and the extraction method of TCM decoction was developed. In the quantitative analysis by HPLC, choline chloride phenol was selected as the eutectic solvent, THF was used as the extractant, and investigation of DES type, DES molar ratio, DES-to-THF ratio, vortex time, and material-to-liquid ratio was carried out. The experimental results showed that the optimal extraction method was as follows: the molar ratio of DES was 1 : 3, and the material-liquid ratio was 5 : 1200 (mL/μL). The volume ratio of DES to THF was 1200 : 800 (μL), the vortex time was 3 min, and the extraction was repeated two times. The eutectic solvent liquid phase microextraction method was adopted to optimize the extraction method of SD and reduce the complicated processing, long time, and low efficiency of traditional methods. At the same time, in the mouse ammonia water inducing cough and phenol red excretion and expectorant experiments, SD high- and medium-dose groups have a significant inhibitory effect on the frequency of antitussive in mice and both can increase the excretion of phenol red to varying degrees, indicating that SD has good cough-relieving and expectorant effect. The present study suggests a scientific basis and basis for the clinical research and quality standard formulation of SD.

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Structural elucidation of lignins from corncob acid hydrolysis residue by enzymatic mild acidolysis and deep eutectic solvent pretreatment

BioResources ◽

10.15376/biores.15.2.4362-4372 ◽

2020 ◽

Vol 15 (2) ◽

pp. 4362-4372

Author(s):

Na Li ◽

Chao Cao ◽

Lupeng Shao ◽

Chao Wang ◽

Yu Liu ◽

...

Keyword(s):

Acid Hydrolysis ◽

31P Nmr ◽

Structural Characteristics ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Gel Permeation Chromatography ◽

Structural Features ◽

Molar Ratio ◽

Efficient Extraction ◽

Hydrolysis Residue

Achieving mild and efficient extraction of high purity lignin from corncob acid hydrolysis residue is essential for efficient lignin application. In this study, enzymatic/mild acidolysis lignin (EMAL) and deep eutectic solvent (DES)-lignin were extracted from corncob acid hydrolysis residue. The structural features of the two lignin fractions were investigated by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), and 31P-nuclear magnetic resonance (31P-NMR). The highest DES-lignin yield of 58.8 wt% was achieved at 120 °C with a choline chloride-to-lactic acid (ChCl-to-Lac) molar ratio of 1:10 and a reaction time of 12 h. The FTIR analysis indicated a higher amount of guaiacyl units in EMAL than DES-lignin. Furthermore, condensation and fragmentation occurred simultaneously under DES pretreatment, but the fragmentation reaction was dominant. The structural characteristics investigated will allow for more effective lignin usage.

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Synthesis of 5-Hydroxymethylfurfural from Cassava (Manihot utilissima pohl) Peels through Dehydration Reaction using Deep Eutectic Solvent Based on Choline Chloride/Citric Acid

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.22374 ◽

2021 ◽

Vol 33 (5) ◽

pp. 1115-1119

Author(s):

R. Manurung ◽

H. Silalahi ◽

O. Winda ◽

A.G. Siregar

Keyword(s):

Citric Acid ◽

Reaction Temperature ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Deep Eutectic Solvents ◽

Cellulose Content ◽

Dehydration Reaction ◽

Reaction Conditions ◽

Hydrolysis Of ◽

Cassava Peel

The high cellulose content in cassava peel has an opportunity to produce bio-based chemical products in 5-hydroxymethylfurfural (5-HMF) form. This study aimed to determine the optimum conditions of glucose dehydration reaction as a result of hydrolysis of the best cassava peel cellulose. The variables observed in this study were H2SO4 catalyst concentrations in the hydrolysis reaction, temperature and amount of deep eutectic solvents based on choline chloride/citric acid. The optimum dehydration reaction conditions in this study was the glucose:deep eutectic solvents mass ratio of 1:6 at the reaction temperature of 80 ºC. The highest yield of 64.50% at an initial glucose concentration of 5.70% using a 1.5% H2SO4 catalyst during the hydrolysis of cassava peel cellulose. The results obtained in this study indicated that addition of choline chloride/citric acid as deep eutectic solvent can increase the yield of 5-HMF.

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Effect of Extraction Time on Unreacted Oil Removal in Biodiesel Purification Using Deep Eutectic Solvent

REAKTOR ◽

10.14710/reaktor.18.2.122-127 ◽

2018 ◽

Vol 18 (2) ◽

pp. 122

Author(s):

Helda Niawanti ◽

Siti Zullaikah

Keyword(s):

Rice Bran Oil ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Acid Methyl Ester ◽

Operating Conditions ◽

Biodiesel Production ◽

Extraction Time ◽

Molar Ratio ◽

Oil Removal ◽

Oil Purification

Rice bran oil (RBO) based biodiesel contains unreacted oil such as monoglyceride (MG), diglyceride (DG) and triglyceride (TG) to be purified. The liquid-liquid extraction (LLE) method was used for purification using Deep Eutectic Solvent (DES). The objective of this work was to study the effect of extraction time on unreacted oil removal. RBO containing 16.49% oil with free fatty acids (FFA) content of 44.75%. Acid catalyzed methanolysis was used for biodiesel production under operating conditions: T = 60°C, t = 8 hours, molar ratio of oil/methanol was 1/10, H2SO4 1% w/w of RBO. Crude biodiesel containing 89.05% fatty acid methyl ester (FAME), 0.05% FFA, TG 4.03%, DG 4.01% and MG 0.30%. DES was made from choline chloride and ethylene glycol with 1/2 molar ratio, while molar ratio of biodiesel/DES was 1/2. The extraction time was varied from 15 to 240 minutes at 30°C. The highest TG, DG and MG removal were obtained at 240 minutes, they were 3.01%, 0.22% and 0.03%, respectively. FAME and FFA content were 96.55% and 0.03%. Keywords: biodiesel; DES; extraction; unreacted oil; purification

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Characterization of Lignin Extracted from Willow by Deep Eutectic Solvent Treatments

Polymers ◽

10.3390/polym10080869 ◽

2018 ◽

Vol 10 (8) ◽

pp. 869 ◽

Cited By ~ 13

Author(s):

Gaojin Lyu ◽

Tengfei Li ◽

Xingxiang Ji ◽

Guihua Yang ◽

Yu Liu ◽

...

Keyword(s):

Choline Chloride ◽

Deep Eutectic Solvent ◽

Molar Ratio ◽

Total Phenolic ◽

Aryl Ether ◽

Hydroxyl Content ◽

Force Microscopy ◽

Molecular Weights ◽

Lignin Extraction

Purity, morphology, and structural characterization of synthesized deep eutectic solvent (DES)-lignins (D6h, D9h, D12h, D18h, D24h) extracted from willow (Salix matsudana cv. Zhuliu) after treatment with a 1:10 molar ratio of choline chloride and lactic acid at 120 °C for 6, 9, 12, 18, and 24 h were carried out. The purity of DES-lignin was ~95.4%. The proportion of hydrogen (H) in DES-lignin samples increased from 4.22% to 6.90% with lignin extraction time. The DES-lignin samples had low number/weight average molecular weights (1348.1/1806.7 to 920.2/1042.5 g/mol, from D6h to D24h) and low particle sizes (702–400 nm). Atomic force microscopy (AFM) analysis demonstrated that DES-lignin nanoparticles had smooth surfaces and diameters of 200–420 nm. Syringyl (S) units were dominant, and total phenolic hydroxyl content and total hydroxyl content reached their highest values of 2.05 and 3.42 mmol·g−1 in D12h and D6h, respectively. β-Aryl ether (β-O-4) linkages were eliminated during DES treatment.

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NADES-based fractionation of biomass to produce raw material for the preparation of cellulose acetates

Cellulose ◽

10.1007/s10570-020-03251-1 ◽

2020 ◽

Vol 27 (12) ◽

pp. 6831-6848

Author(s):

L. A. Soto-Salcido ◽

I. Anugwom ◽

L. Ballinas-Casarrubias ◽

M. Mänttäri ◽

M. Kallioinen

Keyword(s):

Choline Chloride ◽

Deep Eutectic Solvent ◽

Raw Material ◽

Molar Ratio ◽

Sodium Chlorite ◽

Waste Biomass ◽

Birch Wood ◽

Fractionation Process ◽

Wide Range ◽

Cellulose Acetates

Abstract Waste biomass (agave bagasse) and native birch wood were used as raw materials for a novel fractionation and derivation process to produce cellulose acetates (CAs). During the first stage of the fractionation process, a significant amount of hemicelluloses and lignin were dissolved from the biomass using a natural deep eutectic solvent (NADES) that consisted of a mixture of choline chloride and lactic acid with the molar ratio of 1:9. Then, the residual solid material was delignified by bleaching it with a mixture of acetic acid and sodium chlorite. The fractionation process generated differently purified pulps (celluloses) which were converted to CAs. The crystallinity index, polymerization degree, chemical composition, and thermal properties of the differently purified pulps and CAs were analyzed to evaluate the efficacy of the acetylation process and to characterize the CAs. The chemical derivation of the differently purified cellulose samples generated CAs with different degrees of substitution (DSs). The more purified the cellulose sample was, the higher its DS was. Moreover, some differences were observed between the acetylation efficiencies of birch and agave bagasse. Typically, cellulose purified from birch by treating it with NADES followed by bleaching was acetylated more completely (DS = 2.94) than that derived from agave bagasse (DS = 2.45). These results revealed that using green solvents, such as NADES, to treat both agave bagasse (waste biomass) and birch wood, allowed pure fractions to be obtained from biomass, and thus, biomass could be valorized into products such as CAs, which present a wide range of applications.

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