A comparison of methods for obtaining nanocellulose using acid and ionic liquid hydrolysis reactions

2019 ◽  
Vol 107 ◽  
pp. 19-23
Author(s):  
MARTA BABICKA ◽  
IZABELA RATAJCZAK ◽  
KRZYSZTOF DWIECKI
Keyword(s):  
Particle Size ◽  
Ionic Liquid ◽  
Acid Hydrolysis ◽  
Chemical Structure ◽  
Comparison Of Methods ◽  
Material Particle ◽  
Before And After ◽  
Scattering Study ◽  
Nanometric Size ◽  
Hydrolysis Reactions

A comparison of methods for obtaining nanocellulose using acid and ionic liquid hydrolysis reactions. In this study, two methods were compared, i.e. acid hydrolysis using sulphuric acid (VI) and ionic liquid hydrolysis using 1-methyl-3-butylimidazolium chloride to obtain nanocellulose from Sigmacell Cellulose Type 20. The efficiency of both processes was tested for weight loss of the material during the reaction. The study showed that much more material can be obtained using ionic liquid hydrolysis than using acid hydrolysis. A dynamic light scattering study was performed to determine material particle size before and after these processes. Particles of nanometric size were recorded only for cellulose after the reaction with an ionic liquid. In addition, Fourier transform infrared spectroscopy was performed to determine the chemical structure of the materials tested.

Novel Electro Polymerization Method to Synthesized Anti-corrosion Coated Layer on Stainless Steel Surface from (N-Benzothiazolyl Maleamic Acid) and Study its Biological Activity

2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Muna I Khalaf ◽  
Khulood A Saleh ◽  
Khalil S Khalil
Keyword(s):  
Stainless Steel ◽  
Chemical Structure ◽  
Inhibition Efficiency ◽  
Steel Plate ◽  
Polymeric Coating ◽  
Stainless Steel Surface ◽  
Plate Electrode ◽  
Before And After ◽  
Maleamic Acid ◽  
Polymerization Method

Electro polymerization of N-benzothiazolyl maleamic acid (NBM) was carried out on stainless steel plate electrode in a protic medium of monomer aqueous solution using electrochemical oxidation procedure in electrochemical cell.Spectroscopic characterization techniques were investigated to obtain information about the chemical structure of polymer. The anti-corrosion action of polymer was investigated on stainless steel by electrochemical polarization method. In addition, the effect of adding nanomaterial (TiO2, ZnO (bulk-nano)) to monomer solution on the corrosion behavior of stainless steel was investigated. The results obtained showed that the corrosion rate of S-steel increased with temperature increase from 293K to 323K and the values of inhibition efficiency by coating polymer increase with nanomaterial addition. Apparent energies of activation have been calculated for the corrosion process of S-steel in acidic medium before and after polymeric coating. Furthermore were studied the effect of the preparing polymer on some strain of bacteria.

scholarly journals Leaching Behaviour of Construction and Demolition Wastes and Recycled Aggregates: Statistical Analysis Applied to the Release of Contaminants

2021 ◽  
Vol 11 (14) ◽  
pp. 6265
Author(s):  
Alessandra Diotti ◽  
Giovanni Plizzari ◽  
Sabrina Sorlini
Keyword(s):  
Particle Size ◽  
Statistical Analysis ◽  
Raw Materials ◽  
Primary Source ◽  
Recycled Aggregates ◽  
Critical Parameters ◽  
Material Particle ◽  
Analysis Methodology ◽  
Construction And Demolition Wastes ◽  
Leaching Behaviour

Construction and demolition wastes represent a primary source of new alternative materials which, if properly recovered, can be used to replace virgin raw materials partially or totally. The distrust of end-users in the use of recycled aggregates is mainly due to the environmental performance of these materials. In particular, the release of pollutants into the surrounding environment appears to be the aspect of greatest concern. This is because these materials are characterized by a strong heterogeneity which can sometimes lead to contaminant releases above the legal limits for recovery. In this context, an analysis of the leaching behaviour of both CDWs and RAs was conducted by applying a statistical analysis methodology. Subsequently, to evaluate the influence of the particle size and the volumetric reduction of the material on the release of contaminants, several experimental leaching tests were carried out according to the UNI EN 12457-2 and UNI EN 12457-4 standards. The results obtained show that chromium, mercury, and COD are the most critical parameters for both CDWs and RAs. Moreover, the material particle size generally affects the release of contaminants (i.e., finer particles showed higher releases), while the crushing process does not always involve higher releases than the sieving process.

Effect of particle size and delignification on the rate of digestion of hemicellulose and cellulose by cellulase in mature pangola grass stems

1983 ◽  
Vol 34 (3) ◽  
pp. 241 ◽  
Author(s):  
CW Ford
Keyword(s):  
Particle Size ◽  
Cell Walls ◽  
Trichoderma Viride ◽  
Structural Features ◽  
Cell Wall Polysaccharides ◽  
Particle Size Reduction ◽  
Digitaria Decumbens ◽  
Hemicellulose Degradation ◽  
Before And After ◽  
The Difference

Stem cell walls of pangola grass (Digitaria decumbens) were ground to two particle sizes (c. 1 and 0.1 mm diameter), and incubated with cellulase (ex. Trichoderma viride) for varying times before and after delignification. Total cell walls finely ground (0.1 mm) with a Spex Shatterbox mill were initially degraded more rapidly (to 24 h) than delignified 1 mm particles. Thereafter the delignified material was solubilized to a greater extent. Subsequent specific determinations of cell wall polysaccharides indicated that delignification increased the rate of hemicellulose degradation to a greater extent than did particle size reduction, whereas the opposite was found for cellulose. The difference between delignified and Spex-ground residues, in terms of the amount of polysaccharide digested, was much greater for cellulose than hemicellulose. It is concluded that structural features play a more important role in limiting cellulase degradation of cellulose than does association with lignin, the reverse being so for hemicellulose.

scholarly journals Experimental Investigation of Wave Velocity-Permeability Model for Granite Subjected to Different Temperature Processing

Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Guanghui Jiang ◽  
Jianping Zuo ◽  
Teng Ma ◽  
Xu Wei
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Wave Velocity ◽  
Pore Fluid ◽  
Rock Matrix ◽  
Permeability Model ◽  
Wave Velocities ◽  
Before And After ◽  
Different Temperatures ◽  
Increasing Temperature

Understanding the change of permeability of rocks before and after heating is of great significance for exploitation of hydrocarbon resources and disposal of nuclear waste. The rock permeability under high temperature cannot be measured with most of the existing methods. In this paper, quality, wave velocity, and permeability of granite specimen from Maluanshan tunnel are measured after high temperature processing. Quality and wave velocity of granite decrease and permeability of granite increases with increasing temperature. Using porosity as the medium, a new wave velocity-permeability model is established with modified wave velocity-porosity formula and Kozeny-Carman formula. Under some given wave velocities and corresponding permeabilities through experiment, the permeabilities at different temperatures and wave velocities can be obtained. By comparing the experimental and the theoretical results, the proposed formulas are verified. In addition, a sensitivity analysis is performed to examine the effect of particle size, wave velocities in rock matrix, and pore fluid on permeability: permeability increases with increasing particle size, wave velocities in rock matrix, and pore fluid; the higher the rock wave velocity, the lower the effect of wave velocities in rock matrix and pore fluid on permeability.

scholarly journals Modification of Chitin Particles with Ionic Liquids Containing Ethyl Substituent in a Cation

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Malgorzata M. Jaworska ◽  
Andrzej Górak ◽  
Joanna Zdunek
Keyword(s):  
Particle Size ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Hydrogen Bonds ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
High Viscosity ◽  
Physical Structure ◽  
Ethyl Group ◽  
Network Of Hydrogen Bonds

Chitin cannot be dissolved in conventional solvents due to the strong inter- and intrasheet network of hydrogen bonds and the large number of crystalline regions. Some ionic liquids (ILs) have been suggested in the literature as possible solvents for chitin. Seven of them, all having an ethyl group as substituent in the cationic ring, have been tested in this work: [Emim][Cl], [Emim][Br], [Emim][I], [Emim][OAc], [Emim][Lact], [Epyr][I], and [EMS][BFSI]. Chitin was insoluble in [EMS][BFSI] while for all other ILs solubility was limited due to high viscosity of solutions and equilibria have not been reached. Changes in physical structure, particle size distribution, and crystallinity of recovered chitin depended on ionic liquid used. Increase in porosity was observed for chitin treated with [Emim][Cl], [Emim][I], [Emim][Br], and [Emim][Lact]; changes in particle size distribution were observed for [Emim][AcOH] and [EMS][BFSI]; increase in crystallinity was noticed for chitin treated with [Epyr][I] while decrease in crystallinity for [Emim][I] was noticed. All tested ionic liquids were reused four times and changes in FTIR spectra could be observed for each IL.

Fabrication of porous polymeric structures using a simple sonication technique for tissue engineering

2017 ◽  
Vol 37 (9) ◽  
pp. 943-951 ◽  
Author(s):  
Alan Saúl Álvarez-Suarez ◽  
Eduardo Alberto López-Maldonado ◽  
Olivia A. Graeve ◽  
Fabián Martinez-Pallares ◽  
Luis Enrique Gómez-Pineda ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Poly Vinyl Alcohol ◽  
Porous Structures ◽  
Average Pore ◽  
Ultrasonic Probe ◽  
Polymeric Scaffolds ◽  
Before And After ◽  
Water Absorption Test ◽  
Sonication Technique ◽  
Polymeric Structures

AbstractPorous polymeric scaffolds have been applied successfully in the biomedical field. This work explores the use of an ultrasonic probe to generate cavitation in a polymeric solution, thus producing pores in the polymeric scaffolds. Porous polymeric structures with average pore sizes ranging from 5 to 63 μm and porosity of 6–44% were fabricated by a process consisting of sonication, flash freezing, and lyophilization of poly(lactic-co-glycolic acid) (PLGA), gelatin (GEL), chitosan (CS) and poly(vinyl alcohol) (PVAL) solutions. Pore structure was characterized by scanning electron microscopy (SEM) and image analysis software. The infrared spectra were analyzed before and after the fabrication process to observe any change in the chemical structure of the polymers. A water absorption test indicated the susceptibility of the samples to retain water in their structure. TGA results showed that GEL experienced degradation at 225°C, CS had a decomposition peak at 280°C, the thermal decomposition of PLGA occurred at 375°C, and PVAL showed two degradation regions. The DSC analysis showed that the glass transition temperature (Tg) of GEL, CS, PLGA and PVAL occurred at 70°C, 80°C, 60°C and 70°C, respectively. The fabricated porous structures demonstrated similar physical characteristics to those found in bone and cartilage.

scholarly journals Quantification of phenolic compounds by capillary zone electrophoresis in extracts of four commercial types of mate herb before and after acid hydrolysis

2012 ◽  
Vol 48 (2) ◽  
pp. 763-768 ◽  
Author(s):  
Carolina Schaper Bizzotto ◽  
Adriana Dillenburg Meinhart ◽  
Ana Cecília Poloni Rybka ◽  
Merenice Roberto Sobrinho ◽  
Stanislau Bogusz Junior ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Acid Hydrolysis ◽  
Capillary Zone Electrophoresis ◽  
Zone Electrophoresis ◽  
Before And After ◽  
Capillary Zone

scholarly journals Small-angle neutron scattering study of a dense microemulsion system formed with an ionic liquid

Soft Matter ◽  
2017 ◽  
Vol 13 (39) ◽  
pp. 7154-7160 ◽  
Author(s):  
T. Kang ◽  
S. Qian ◽  
G. S. Smith ◽  
C. Do ◽  
W. T. Heller
Keyword(s):  
Ionic Liquid ◽  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Composition Series ◽  
Microemulsion System ◽  
Structure And Properties ◽  
Scattering Study ◽  
Neutron Scattering Study ◽  
Systematic Composition

The structure of the microemulsion formed with an Ionic Liquid (IL) in specific systematic composition series has been investigated by small-angle neutron scattering to understand how the IL can be used to tune the structure and properties of microemulsions.

Assessment of Lost Circulation Material Particle-Size Distribution on Fracture Sealing: A Numerical Study

2022 ◽  
pp. 1-15
Author(s):  
Lu Lee ◽  
Arash Dahi Taleghani
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Numerical Study ◽  
Fluid Loss ◽  
Material Particle ◽  
Lost Circulation ◽  
Fracture Sealing ◽  
Discrete Element Methods ◽  
Lost Circulation Materials

Summary Lost circulation materials (LCMs) are essential to combat fluid loss while drilling and may put the whole operation at risk if a proper LCM design is not used. The focus of this research is understanding the function of LCMs in sealing fractures to reduce fluid loss. One important consideration in the success of fracture sealing is the particle-size distribution (PSD) of LCMs. Various studies have suggested different guidelines for obtaining the best size distribution of LCMs for effective fracture sealing based on limited laboratory experiments or field observations. Hence, there is a need for sophisticated numerical methods to improve the LCM design by providing some predictive capabilities. In this study, computational fluid dynamics (CFD) and discrete element methods (DEM) numerical simulations are coupled to investigate the influence of PSD of granular LCMs on fracture sealing. Dimensionless variables were introduced to compare cases with different PSDs. We validated the CFD-DEM model in reproducing specific laboratory observations of fracture-sealing experiments within the model boundary parameters. Our simulations suggested that a bimodally distributed blend would be the most effective design in comparison to other PSDs tested here.

CO2 Capture by Supported Ionic Liquid Phase: Highlighting the Role of the Particle Size

2019 ◽  
Vol 7 (15) ◽  
pp. 13089-13097 ◽  
Author(s):  
Ruben Santiago ◽  
Jesus Lemus ◽  
Daniel Hospital-Benito ◽  
Cristian Moya ◽  
Jorge Bedia ◽  
...  
Keyword(s):  
Particle Size ◽  
Ionic Liquid ◽  
Liquid Phase ◽  
Co2 Capture ◽  
Supported Ionic Liquid
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