Preparation of nanocellulose by hydrolysis with ionic liquids and two-step hydrolysis with ionic liquids and enzymes

2021 ◽  
Vol 116 ◽  
pp. 5-14
Author(s):  
Marta Babicka ◽  
Magdalena Woźniak ◽  
Kinga Szentner ◽  
Sławomir Borysiak ◽  
Krzysztof Dwiecki ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Degree Of Crystallinity ◽  
Cellulolytic Enzyme ◽  
X Ray Diffraction ◽  
Production Methods ◽  
Step Process ◽  
X Ray ◽  
One Step ◽  
Xrd Patterns ◽  
The One

The aim of this study was to compare parameters of nanocellulose obtained by two different procedures: hydrolysis with ionic liquids (1-allyl-3-methylimidazolium chloride and 1-ethyl-3-methylimidazolium acetate) and hydrolysis with ionic liquids in combination with hydrolysis using a cellulolytic enzyme from Trichoderma reesei. Avicel cellulose was treated with two ionic liquids: 1-allyl-3-methylimidazolium chloride (AmimCl) and 1-ethyl 3-methylimidazolium acetate (EmimOAc). In the two-step hydrolysis cellulose after treatment with ionic liquids was additionally hydrolyzed with a solution of enzymes. In order to characterize the obtained material, the following analyses were used: infrared spectroscopy, X-ray diffraction and dynamic light scattering. The results indicated that cellulose obtained by two-step nanocellulose production methods (first hydrolysis with ionic liquids and then with enzymes) showed similar parameters (particle size, XRD patterns and degree of crystallinity) as the material after the one-step process, i.e. hydrolysis with ionic liquids.

scholarly journals Characterization of Serpentines from Different Regions by Transmission Electron Microscopy, X-ray Diffraction, BET Specific Surface Area and Vibrational and Electronic Spectroscopy

Fibers ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 47 ◽  
Author(s):  
Miguel A. Rivero Crespo ◽  
Dolores Pereira Gómez ◽  
María V. Villa García ◽  
José M. Gallardo Amores ◽  
Vicente Sánchez Escribano
Keyword(s):  
Electron Microscopy ◽  
Relative Intensity ◽  
Electronic Spectroscopy ◽  
Visible Region ◽  
Band Gap Energy ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Oh Groups ◽  
X Ray ◽  
Xrd Patterns

Serpentinite powdered samples from four different regions were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), SBET and porosity measurements, UV-Vis and Infrared Spectroscopy of the skeletal region and surface OH groups. SEM micrographs of the samples showed a prismatic morphology when the lizardite was the predominant phase, while if antigorite phase prevailed, the particles had a globular morphology. The few fibrous-shaped particles, only observed by SEM and weakly detected by XRD on MO-9C and MO13 samples, were characteristic of the chrysotile phase. All diffraction XRD patterns showed characteristic peaks of antigorite and lizardite serpentine phases, with crystallite sizes in the range 310–250 Å and with different degrees and types of carbonation processes, one derived from the transformation of the serpentine, generating dolomite, and another by direct precipitation of calcite. The SBET reached values between 38–24 m2∙g−1 for the samples less crystalline, in agreement with the XRD patterns, while those with a higher degree of crystallinity gave values close to 8–9 m2∙g−1. In the UV region all electronic spectra were dominated by the absorption edge due to O2− → Si4+ charge transfer transition, with Si4+ in tetrahedral coordination, corresponding to a band gap energy of ca 4.7 eV. In the visible region, 800–350 nm, the spectra of all samples, except Donai, presented at least two weak and broad absorptions centred in the range 650–800 and 550–360 nm, associated with the presence of Fe3+ ions from the oxidation of structural Fe2+ ions in the serpentinites ((MgxFe2+1−x)3Si2O5(OH)4). The relative intensity of the IR bands corresponding to the stretching modes of the OH’s groups indicated the prevalence of one of the two phases, antigorite or lizardite, in the serpentinites. We proposed that the different relative intensity of these bands could be considered as diagnostic to differentiate the predominance of these phases in serpentinites.

Sonochemical Co-Precipitation Synthesis of Gallic Acid-Modified Magnetite

2015 ◽  
Vol 1101 ◽  
pp. 286-289 ◽  
Author(s):  
Maya Rahmayanti ◽  
Sri Juari Santosa ◽  
Sutarno
Keyword(s):  
Magnetic Properties ◽  
Gallic Acid ◽  
Precipitation Method ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
One Step ◽  
The Fourier Transform ◽  
The One ◽  
Co Precipitation

Gallic acid-modified magnetites were synthesized by one and two-step reactions via the newly developed sonochemical co-precipitation method. The two-step reaction included the formation of magnetite powder and mixing the magnetite powder with gallic acid solution, while the one-step reaction did not go through the formation magnetite powder. The obtained gallic acid-modified magnetites were characterized by the Fourier Transform Infrared (FTIR) spectroscopy, the X-Ray Diffraction (XRD) and the Scanning Electron Microscopy (SEM). More over, the magnetic properties were studied by using a Vibrating Sample Magnetometer (VSM). The characterization results showed that there were differences in crystalinity, surface morphology and magnetic properties of products that were formed by one and two-step reactions.

One Step Synthesis of Graphene-Like Structures by Carbonization of some Carbohydrates in Molten Salt Media

2019 ◽  
Vol 59 ◽  
pp. 166-179 ◽  
Author(s):  
Betül Gürünlü ◽  
Mahmut Bayramoğlu
Keyword(s):  
Molten Salt ◽  
Photoelectron Spectroscopy ◽  
Synthesis Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hummers Method ◽  
Environmental Friendly ◽  
One Step ◽  
Xrd Patterns ◽  
Molten Salt System

Graphene is one of the most promising materials discovered in last years. It is usually synthesized by Hummers’ method requiring the usage of many chemicals. As an alternative to traditional methods, in this study a bottom-up synthesis method was developed from various saccharides such as starch, mannose, cellulose, fructose, arabinose, and xylose by carbonization at 600 °C to 800 °C in LiCl/KCl molten salt system. The proposed method is environmental friendly and economic. Graphene yields at 600 °C are higher than at 800 °C. Graphene products give peak at 2θ = 23° on the X-Ray Diffraction (XRD) patterns. As the temperature is increased, amorph structure is observed on the XRD patterns. Raman spectroscopy results show that intensity of D band peak over intensity of G band peak (ID/IG) values of graphene products synthesized from arabinose and cellulose at 600 °C, graphene from arabinose synthesized at 800 °C are 0.76, 0.65 and 0.85 respectively, which show that these products are few-layered. According to X-ray photoelectron spectroscopy (XPS) results, graphene products synthesized at 600 °C have higher carbon content than those synthesized at 800 °C.

Dilatometer Analysis of the One Step Quenching and Partitioning Process in a 1.5%Si Steel

2014 ◽  
Vol 783-786 ◽  
pp. 880-885
Author(s):  
David Martin ◽  
Johan Eliasson ◽  
Bengt Brolund ◽  
Ylva Granbom
Keyword(s):  
Phase Transformation ◽  
X Ray Diffraction ◽  
Quenching And Partitioning ◽  
X Ray ◽  
Final Microstructure ◽  
Different Temperatures ◽  
One Step ◽  
The One ◽  
Step Quenching ◽  
Quenching And Partitioning Process

A one step quenching and partitioning process was applied to a 0.2%C-2.0%Mn-0.5%Cr-1.5%Si steel by quenching austenitised samples to several different temperatures below the experimentallydetermined martensite start temperature of 397 °C and isothermally partitioning them beforequenching to room temperature using a quenching deformation dilatometer. These treatmentsyielded predominantly martensitic microstructures containing 5.6 vol.% to 7.5 vol.% retained austenite,as measured by x-ray diffraction. In each treatment, strong dilation was recorded during isothermalpartitioning, with little indication of phase transformation during subsequent cooling to room temperature.This behaviour lends weight to the idea that an isothermal phase transformation occurred duringpartitioning, and that the final microstructure is a mixture of athermally and isothermally formed constituents.These results also suggest that the final microstructure of this steel is mostly formed beforeand during partitioning.

Preparation of Ag-Modified CaBiO2Cl and its Photocatalytic Ability under Visible Light

2014 ◽  
Vol 955-959 ◽  
pp. 120-126
Author(s):  
Ying Feng ◽  
Wei Huang ◽  
Chao Hao Hu ◽  
Wen Zhao ◽  
Pan Fei Jiao ◽  
...  
Keyword(s):  
Visible Light ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Photocatalytic Ability ◽  
Reaction Method ◽  
X Ray ◽  
Photocatalytic Activities ◽  
One Step ◽  
The One ◽  
Scanning Electron

Ag-modified CaBiO2Cl photocatalysts were synthesized by the one-step solid state reaction method. The microstructure and morphology of catalysts were characterized by using X-ray diffraction, Scanning electron microscopy, and Energy dispersive X-ray detector (EDS) techniques. The photocatalytic activities of pure CaBiO2Cl and Ag-CaBiO2Cl catalysts were further evaluated by degrading methylene blue (MB) under visible-light irradiation. The measured UV-vis absorption spectra indicated that the degradation of Ag-modified CaBiO2Cl has been improved by about 12% in comparison with pure CaBiO2Cl. The enhanced photocatalytic activity in Ag-modified CaBiO2Cl can be ascribed to the better morphologies of the composites due to the Ag additive.

Comparative Study on Mn-Zn Ferrites by One-Step Synthesis and Conventional Two-Step Synthesis

2010 ◽  
Vol 177 ◽  
pp. 260-263 ◽  
Author(s):  
Qing Kai Xing ◽  
Zhi Jian Peng ◽  
Xiu Li Fu ◽  
Zhi Qiang Fu ◽  
Cheng Biao Wang ◽  
...  
Keyword(s):  
Magnetic Hysteresis ◽  
Initial Permeability ◽  
Synthesis Methods ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Magnetic Performance ◽  
One Step ◽  
The Difference ◽  
The One

Mn-Zn ferrites doped with Cr3+ were prepared by “one-step synthesis” and conventional two-step synthesis methods, respectively. Their phase compositions and microstructures were characterized by X-ray diffraction and scanning electron microscopy, respectively. And their magnetic magnetic performance, such as saturation magnetization (Ms), magnetic hysteresis, initial permeability μi and power loss were comparatively investigated by vibrating sample magnetometer. It was observed that the difference of magnetic performance of the samples prepared by both methods is little. The similar performance of both methods makes the “one-step synthesis” especially attractive for application when considering energy economization.

scholarly journals The Comparison Of Different Activation Techniques To Prepare Activated Carbon Materials From Waste Cotton Fabric

2017 ◽  
Vol 17 (3) ◽  
pp. 287-294
Author(s):  
Hou Wensheng Wang Shuahua ◽  
Wei Meixia ◽  
Xu Qiaoli ◽  
Niu Mei
Keyword(s):  
Cotton Fabric ◽  
Carbon Materials ◽  
Activated Carbons ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Step Process ◽  
X Ray ◽  
One Step ◽  
Carbon Network ◽  
Macroporous Carbon

AbstractIn this paper, we investigate on the preparation of waste cotton fabric-based activated carbons by different methods. Two different kinds of carbon materials are prepared from waste cotton fabric, the structure and properties were characterized using instrumental analyses such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). It is revealed that the products prepared using one-step process are composed of macroporous carbon network , which looks like sponge-type morphology, and exhibit the high values of qiodine(1,198 mg/g) and qmb(235.6 ml/g), showing their potential usage as adsorbent.

The effect of the time process of enzymatic hydrolysis on nanocellulose properties

2021 ◽  
Vol 115 ◽  
pp. 101-107
Author(s):  
Marta Babicka ◽  
Magdalena Wożniak ◽  
Kinga Szentner ◽  
Sławomir Borysiak ◽  
Krzysztof Dwiecki ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Reaction Times ◽  
Raw Material ◽  
Degree Of Crystallinity ◽  
Cellulolytic Enzyme ◽  
Time Process ◽  
X Ray Diffraction ◽  
Hydrolysis Time ◽  
Xrd Patterns ◽  
Cellulose Materials

The effect of the time process of enzymatic hydrolysis on nanocellulose properties - the aim of the study was to evaluate the effect of enzymatic hydrolysis time on the properties of obtained nanocellulose. Two cellulose materials were tested as a raw material for nanocellulose production in the experiment: Avicel and Whatman. The cellulolytic enzyme obtained from the fungus Trichoderma reesei was used to carry out the enzymatic hydrolysis reaction. Enzymatic hydrolysis was performed on cellulose using the reaction times of 0.5, 1, 2 and 4 hours. In order to characterize the obtained materials, the following analyses were used: infrared spectroscopy, X-ray diffraction and dynamic light scattering. The recorded results showed that cellulose after enzymatic hydrolysis showed similar parameters (particle size, XRD patterns and degree of crystallinity) after all the applied reaction times.

scholarly journals Investigation of Thermal Behavior of Layered Double Hydroxides Intercalated with Carboxymethylcellulose Aiming Bio-Carbon Based Nanocomposites

2019 ◽  
Vol 3 (2) ◽  
pp. 55
Author(s):  
Vagner R. Magri ◽  
Alfredo Duarte ◽  
Gustavo F. Perotti ◽  
Vera R.L. Constantino
Keyword(s):  
Layered Double Hydroxides ◽  
Mixed Oxides ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Vibrational Spectroscopies ◽  
Xrd Patterns ◽  
Double Hydroxides ◽  
The Degree Of Crystallinity

Carboxymethylcellulose (CMC), a polymer derived from biomass, was intercalated into layered double hydroxides (LDH) composed by M2+/Al3+ (M2Al-CMC, M = Mg or Zn) and evaluated as precursors for the preparation of biocarbon-based nanocomposites by pyrolysis. M2Al-CMC hybrids were obtained by coprecipitation and characterized by X ray diffraction (XRD), vibrational spectroscopies, chemical analysis, and thermal analysis coupled to mass spectrometry. Following, pyrolyzed materials obtained between 500–1000 °C were characterized by XRD, Raman spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Above 600 °C, Raman spectra of all samples showed the presence of graphitic carbon, which plays a role in the degree of crystallinity of produced inorganic phases (for comparison purposes, M2Al-CO3 materials were investigated after calcination in the same experimental conditions). XRD patterns of Mg2Al-CMC pyrolyzed between 600–1000 °C showed poorly crystallized MgO and absence of spinel reflections, whereas for Zn2Al-CMC, it was observed well crystallized nanometric ZnO at 800 °C, and ZnAl2O4 and γ-Al2O3 phases at 1000 °C. Above 800 °C, the carbothermic reaction was noticed, transforming ZnO to zinc vapour. This study opens perspectives for nanocomposites preparation based on carbon and inorganic (mixed) oxides through precursors having organic-inorganic interactions at the nanoscale domain.

Effect of Ethylene Sulphite on the Conductivity and Morphology of PEO-KOH Films

2006 ◽  
Vol 517 ◽  
pp. 89-92
Author(s):  
M.F. Hassan ◽  
N.H. Idris ◽  
S.R. Majid ◽  
Tan Winie ◽  
A.S.A. Khiar ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrochemical Impedance ◽  
Degree Of Crystallinity ◽  
Number Density ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrd Patterns ◽  
Mobile Ions ◽  
The Degree Of Crystallinity ◽  
Scanning Electron

The plasticized PEO-KOH films have been investigated using the electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The conductivity of films increased by about 2 orders of magnitude from 10-5 to 10-3 S cm-1 at r.t. on addition of 0.5 wt.% of ethylene sulphite (ES). The degree of crystallinity was calculated from the XRD patterns. SEM micrographs show that the plasticized films were porous. The highest conductivity of plasticized films at r.t. was (1.3 ± 0.2) x 10-3 S cm-1 for the film with 0.5 wt.% of ES content. The number density of mobile ions was shown to increase indicating that ES has dissociated more salts into ions and thereby increasing the conductivity.

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