scholarly journals Characterization of Eucalyptus nitens Lignins Obtained by Biorefinery Methods Based on Ionic Liquids

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 425 ◽  
Author(s):  
Lucía Penín ◽  
Heiko Lange ◽  
Valentín Santos ◽  
Claudia Crestini ◽  
Juan Carlos Parajó
Keyword(s):  
Ionic Liquid ◽  
31P Nmr ◽  
Solid Phase ◽  
Gel Permeation Chromatography ◽  
Structural Features ◽  
Eucalyptus Nitens ◽  
Hydrogen Sulfate ◽  
Hydrothermal Processing ◽  
Lignin Recovery

Eucalyptus nitens wood samples were subjected to consecutive stages of hydrothermal processing for hemicellulose solubilization and delignification with an ionic liquid, i.e., either 1-butyl-3-methylimidazolium hydrogen sulfate or triethylammonium hydrogen sulfate. Delignification experiments were carried out a 170 °C for 10–50 min. The solid phases from treatments, i.e., cellulose-enriched solids, were recovered by centrifugation, and lignin was separated from the ionic liquid by water precipitation. The best delignification conditions were identified on the basis of the results determined for delignification percentage, lignin recovery yield, and cellulose recovery in solid phase. The lignins obtained under selected conditions were characterized in deep by 31P-NMR, 13C-NMR, HSQC, and gel permeation chromatography. The major structural features of the lignins were discussed in comparison with the results determined for a model Ionosolv lignin.

Synthesis and Characterization of Poly Phenoxyl Bisphenol-S Phosphate

2012 ◽  
Vol 535-537 ◽  
pp. 1091-1094
Author(s):  
Da Ming Ban ◽  
Yang Min ◽  
Yong Hang Zhang ◽  
Ou Zhao
Keyword(s):  
Molecular Weight ◽  
Solid Phase ◽  
Phosphorus Oxychloride ◽  
Orthogonal Design ◽  
Influence Factors ◽  
Gel Permeation Chromatography ◽  
Decomposition Temperature ◽  
Gravimetric Analysis ◽  
Bisphenol S

A solid phase bisphenol-S bis(diphenyl phosphate)(BSDP), Poly Phenoxyl Bisphenol-S Phosphate（S-BSDP）was synthesized from phosphorus oxychloride, phenol and bisphenol-A in two step sythesis route. The influence factors on the yield and molecular weight of S-BSDP were investigated by the means of orthogonal design. The structure of S-BSDP was characterized with Fourier Transform Infrared Spectroscopy (FTIR). The molecular weight was determined by Gel Permeation Chromatography (GPC). Thermal stability of S-BSDP was studied by Thermal Gravimetric Analysis (TGA). The results review that S-BSDP was synthesized successfully and its structure is similar to BSDP. Its thermal decomposition temperature is much higher than liquid phase BSDP.

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

BioResources ◽  
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.

scholarly journals Structural and Thermal Characterization of Novel Organosolv Lignins from Wood and Herbaceous Sources

Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 860 ◽  
Author(s):  
Anna Trubetskaya ◽  
Heiko Lange ◽  
Bernd Wittgens ◽  
Anders Brunsvik ◽  
Claudia Crestini ◽  
...  
Keyword(s):  
Thermogravimetric Analysis ◽  
Gel Permeation Chromatography ◽  
Thermal Characterization ◽  
Structural Features ◽  
Isolation Method ◽  
Structural Variations ◽  
Gel Permeation ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

This study demonstrates the effects of structural variations of lignins isolated via an organosolv process from different woody and herbaceous feedstocks on their thermal stability profiles. The organosolv lignins were first analysed for impurities, and structural features were determined using the default set of gel permeation chromatography, FT-IR spectroscopy, quantitative 31 P NMR spectroscopy and semi-quantitative 1 H- 13 C HSQC analysis. Pyrolysis-, O 2 - and CO 2 -reactivity of the organosolv lignins were investigated by thermogravimetric analysis (TGA), and volatile formation in various heating cycles was mapped by head-space GC-MS analysis. Revealed reactivities were correlated to the presence of identified impurities and structural features typical for the organosolv lignins. Data suggest that thermogravimetric analysis can eventually be used to delineate a lignin character when basic information regarding its isolation method is available.

scholarly journals Synthesis and Characterization of Poly(aryleneethynylene)s and Their Corresponding Platinum-Linked Polymers

2011 ◽  
Vol 3 (3) ◽  
pp. 587-597 ◽  
Author(s):  
M. I. Hossain ◽  
D. Debnath ◽  
M. Younis ◽  
M. A. Bari ◽  
M. A. J. Miah
Keyword(s):  
Oxidative Coupling ◽  
Nmr Spectra ◽  
31P Nmr ◽  
Gel Permeation Chromatography ◽  
Degree Of Polymerization ◽  
Synthesis And Characterization ◽  
Organometallic Polymers ◽  
Organic Polymers ◽  
Gel Permeation

A series of thermally stable organic polymers [poly(2,5-diethynylpyridine] (5), [poly(1,4- diethynyl benzene)] (6), [poly(2,5-dialkyl-p-phenyleneethynylene)] (7), and [poly(p,p-diethynylbiphenyl)] (8), were synthesized by the reaction between diterminal aryleneethynylene, [HCCArCCH] {Ar = C5H5N (1); Ar = C6H6 (2); Ar = C6H4(CH3)2 (3); Ar = C6H4-C6H4 (4)} and CuCl in pyridine by Hay’s oxidative coupling method. Then the organometallic polymers [Ph (PnBu3)2Pt-C≡C-(Ar-C≡C-C≡C)n-Pt((PnBu3)2Ph] {Ar = C5H5N (9); Ar = C6H6 (10); Ar = C6H4(CH3)2 (11); Ar = C6H4-C6H4 (12)}   were synthesized by the reaction of organic polymers 5, 6, 7 and 8 with metal precursor (PnBu3)2 PtPhCl in diethylisopropileamine with good yield. These metal-linked polymers were characterized by IR, 1H-NMR, 13C-NMR and 31P-NMR spectra. Finally the molecular weight of the organometallic polymers (9, 10, 11 and 12) was determined by gel permeation chromatography (GPC). It is clearly observed from GPC that the polymers were synthesized with different degree of polymerization. Keywords:  Organometallic polymers; Hay’s Oxidative coupling; GPC. © 2011 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: 10.3329/jsr.v3i3.7293               J. Sci. Res. 3 (3), 587-597 (2011)

scholarly journals Characterization of the aroma profile of novel Brazilian wines by solid-phase microextraction using polymeric ionic liquid sorbent coatings

2018 ◽  
Vol 410 (19) ◽  
pp. 4749-4762 ◽  
Author(s):  
Juliana Crucello ◽  
Luiz F. O. Miron ◽  
Victor H. C. Ferreira ◽  
He Nan ◽  
Marcia O. M. Marques ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Aroma Profile ◽  
Polymeric Ionic Liquid

scholarly journals Performance of 1-(3-Sulfopropyl)-3-Methylimidazolium Hydrogen Sulfate as a Catalyst for Hardwood Upgrading into Bio-Based Platform Chemicals

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 937
Author(s):  
Mar López ◽  
Sandra Rivas ◽  
Carlos Vila ◽  
Valentín Santos ◽  
Juan Carlos Parajó
Keyword(s):  
Levulinic Acid ◽  
Solid Phase ◽  
Aqueous Media ◽  
Hydrogen Sulfate ◽  
Hydrothermal Processing ◽  
Isobutyl Ketone ◽  
One Pot ◽  
Operational Conditions ◽  
Platform Chemicals ◽  
The One

The acidic ionic liquid 1-(3-sulfopropyl)-3-methylimidazolium hydrogen sulfate ([C3SO3Hmim]HSO4) was employed as a catalyst for manufacturing polysaccharide-derived products (soluble hemicellulose-derived saccharides, furans, and/or organic acids) from Eucalyptus globulus wood. Operation was performed in aqueous media supplemented with [C3SO3Hmim]HSO4 and methyl isobutyl ketone, following two different processing schemes: one-pot reaction or the solubilization of hemicelluloses by hydrothermal processing followed by the separate manufacture of the target compounds from both hemicellulose-derived saccharides and cellulose. Depending on the operational conditions, the one-pot reaction could be directed to the formation of furfural (at molar conversions up to 92.6%), levulinic acid (at molar conversions up to 45.8%), or mixtures of furfural and levulinic acid (at molar conversions up to 81.3% and 44.8%, respectively). In comparison, after hydrothermal processing, the liquid phase (containing hemicellulose-derived saccharides) yielded furfural at molar conversions near 78%, whereas levulinic acid was produced from the cellulose-enriched, solid phase at molar conversions up to 49.5%.

scholarly journals Structural Characterization of the PawL-Derived Peptide Family, an Ancient Subfamily of Orbitides

2021 ◽  
Author(s):  
Colton D. Payne ◽  
Mark F. Fisher ◽  
Joshua S. Mylne ◽  
K. Johan Rosengren
Keyword(s):  
Disulfide Bonds ◽  
Solid Phase ◽  
Structural Characteristics ◽  
Solid Phase Peptide Synthesis ◽  
Large Family ◽  
Seed Storage ◽  
Structural Features ◽  
Therapeutic Effects ◽  
Evolutionary Origins

Plants are an excellent source of bioactive peptides, often with disulfide bonds and/or a cyclic backbone. While focus has predominantly been directed at disulfide-rich peptides, a large family of small, cyclic but non-disulfide bonded peptides known as the orbitides has been relatively ignored. What research has been conducted has focused on discovering bioactive orbitides, with less attention to structural features. A recently discovered subfamily of the orbitides known as the PawL-Derived Peptides (PLPs) are produced during the maturation of precursors for seed storage albumins. Although their evolutionary origins have been dated, in-depth exploration of the family's structural characteristics and potential bioactivities remains to be conducted. Here we present an extensive characterization of the PLP family. Nine PLPs were produced by solid phase peptide synthesis. Although orbitides can have antimicrobial and therapeutic effects, none of these nine PLPs showed antibacterial or antifungal activity. Their structural features were studied using solution NMR spectroscopy and seven were found to possess regions of backbone order. Ordered regions consist of β-turns, with some PLPs adopting two well-defined β-turns within sequences as short as seven residues, which are largely the result of side chain interactions. Our data highlight that the sequence diversity within this family results in equally diverse shapes.

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