scholarly journals Isolation of cellulose nanocrystals from rice husk using the formic/ peroxyformic acid process

2020 ◽  
Vol 4 (2) ◽  
pp. First
Author(s):  
An Nang Vu ◽  
Nhi Van Nguyen ◽  
Van Thi Thanh Tran ◽  
Nhan Chi Ha Thuc ◽  
Hieu Van Le
Keyword(s):  
Rice Husk ◽  
Cellulose Nanocrystals ◽  
Average Diameter ◽  
Morphological Characterization ◽  
Raw Material ◽  
Transmission Electron ◽  
Hydrolysis Process ◽  
Biomass Resources ◽  
Acid Process ◽  
Peroxyformic Acid

Cellulose nanocrystals (CNCs) is one of the interesting materials attracting many researchers from the decades, especially when they are extracted from natural biomass resources. The  aim  of  this  study  was  to  explore  the  utilization  of  rice husk  residues  as  source  for  the  production  of CNCs. Cellulose was extracted from rice husk based on chemical method, using the formic/ peroxyformic acid process in order to effectively remove lignin and hemicelluloses from raw material. The cellulose was then treated by acid hydrolysis process performing at 45oC for 30 min, using 15 mL of H2SO4 (64% wt) for each gram of cellulose. The  material  obtained  after  each  stage  of the  treatments  was  carefully  characterized  by Fourier  transform  infrared spectroscopy (FTIR), X-ray  diffraction  (XRD) and Transmission electron microscopy (TEM). Morphological characterization from TEM revealed the appearance of needle-like shaped CNCs, average diameter and length  of 15 nm and  480  nm,  respectively. FT-IR results indicated that lignin was completely removed from the samples during chemical treatment. The  thermal  stability  of  the  materials in successive  treatments was  also investigated  using  thermogravimetric  analysis  (TGA). These  promising  results  proved  revalue  of  this  by-product  for  the production  of  CNCs  and  its  potential  use  as  reinforcement  in  the  preparation  of  nanocomposites.

A Study on a Green Route to Preparation of Silica Powders with Rice Husk Ash

2014 ◽  
Vol 1010-1012 ◽  
pp. 1015-1019
Author(s):  
Ze Xin Yang ◽  
Lin Dong ◽  
Meng Wang ◽  
Huan Li
Keyword(s):  
Sodium Bicarbonate ◽  
Sodium Silicate ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Sodium Hydroxide Solution ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Raw Material ◽  
Transmission Electron ◽  
Thermal Analyzer

The main purpose of this article is to develop an environmentally friendly and economically effective process to produce silica from rice husk ash. Sodium silicate solution was prepared by the reaction of rice husk ash and sodium hydroxide solution, and then the sodium silicate solution was used as the raw material for the preparation of silica with sodium bicarbonate. During the reaction, the by-product can be passed into CO2 to prepare sodium bicarbonate what can be reutilized. Experimental route achieved resource recycling and environment-friendly, low energy consumption, zero emissions and so on. Meanwhile the microstructures of the silica powders were characterized by Transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Thermo gravimetric/Differential thermal analyzer (TG-DTA).The purity of silicon was up to 99.43% and the particle size was 200-300nm.

Enzymatic Preparation of Nanocrystalline Cellulose from Bamboo Fibers

2012 ◽  
Vol 441 ◽  
pp. 754-758 ◽  
Author(s):  
Yong Zhang ◽  
Guo Xin Xue ◽  
Xiu Mei Zhang ◽  
Yu Zhao
Keyword(s):  
Enzymatic Hydrolysis ◽  
Average Diameter ◽  
Degree Of Polymerization ◽  
Nanocrystalline Cellulose ◽  
Preparation Process ◽  
Enzymatic Preparation ◽  
Bamboo Pulp ◽  
Transmission Electron ◽  
Hydrolysis Process ◽  
Bamboo Fibers

This paper reports an attempt to prepare nanocrystalline cellulose from bamboo fibers through an enzymatic hydrolysis process. A type of commercial cellulase, viz. enzyme Cclast (mainly containing endoglucanase) was used in the preparation process. The morphology of the prepared bamboo cellulose nanocrystals was characterized by transmission electron microscopy (TEM) and the sugar analyses of hydrolysis residues were analyzed by ion chromatography (IC). The degree of polymerization (DP) was tested by automatic viscosimeter. All nanocrystalline cellulose from bamboo fibers presented a rod-like shape, an average diameter (D) of 5.3 nm and length (L) of 221 nm, with an aspect ratio (L/D) of around 42. It was shown that the use of enzymatic hydrolysis treatment to bleach bamboo pulp helps the preparation of well individualized rod-like nanocrystalline cellulose.

scholarly journals Modification of cellulose nanocrystals with 2-carboxyethyl acrylate in the presence of epoxy resin to enhance its adhesive property

2021 ◽  
Author(s):  
Tariq Aziz ◽  
Jieyuan Zheng ◽  
Sahid Mehmood ◽  
Amjad Ali ◽  
Fazal Haq ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Cellulose Nanocrystals ◽  
Interfacial Adhesion ◽  
Diglycidyl Ether ◽  
Raw Material ◽  
Adhesion Properties ◽  
Transmission Electron ◽  
Epoxy Resin System ◽  
Bisphenol A Diglycidyl Ether ◽  
Modified Cellulose

Abstract We synthesized the cellulose nanocrystals (CNCs) by using cotton as a raw material, then it was modified with 2-carboxyethyl acrylate to improve its adhesion and thermal properties. CNCs was chosen as a modifier to improve the interfacial adhesion between the reinforced nanocrystals and E-51 epoxy resin system. This gives a better modulus of elasticity, a lower coefficient of energy, and thermal expansion. Significant improvements in modulus properties, strength, transparency and thermal stability were observed with modified cellulose nanocrystals (MCNCs) compared with the standard sample. SEM, and transmission electron microscope (TEM), powder diffraction (XRD), (TGA and DTG) and Fourier transform infrared spectroscopy (FTIR) were used for the isolation of synthetic (native and modified) cellulose nanocrystals. In addition, the MCNCs adhesion properties with E-51 (Bisphenol A diglycidyl ether) epoxy resins were also investigated using the Zwick/Roell Z020 model.

A morphological and energy-dispersive x-ray spectroscopy (EDS) investigation of separator-grade cellophane

1994 ◽  
Vol 52 ◽  
pp. 430-431
Author(s):  
Michael E. Rock ◽  
Vern Kennedy ◽  
Bhaskar Deodhar ◽  
Thomas G. Stoebe
Keyword(s):  
Extrusion Process ◽  
Morphological Characterization ◽  
Energy Dispersive ◽  
Regenerated Cellulose ◽  
Battery System ◽  
X Ray ◽  
Functional Differences ◽  
Transmission Electron ◽  
Separator Material ◽  
Underwater Target

Cellophane is a composite polymer material, made up of regenerated cellulose (usually derived from wood pulp) which has been chemically transformed into "viscose", then formed into a (1 mil thickness) transparent sheet through an extrusion process. Although primarily produced for the food industry, cellophane's use as a separator material in the silver-zinc secondary battery system has proved to be another important market. We examined 14 samples from five producers of cellophane, which are being evaluated as the separator material for a silver/zinc alkaline battery system in an autonomous underwater target vehicle. Our intent was to identify structural and/or chemical differences between samples which could be related to the functional differences seen in the lifetimes of these various battery separators. The unused cellophane samples were examined by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS). Cellophane samples were cross sectioned (125-150 nm) using a diamond knife on a RMC MT-6000 ultramicrotome. Sections were examined in a Philips 430-T TEM at 200 kV. Analysis included morphological characterization, and EDS (for chemical composition). EDS was performed using an EDAX windowless detector.

scholarly journals Renewable Biomass Utilization: A Way Forward to Establish Sustainable Chemical and Processing Industries

2021 ◽  
Vol 3 (1) ◽  
pp. 243-259
Author(s):  
Yadhu N. Guragain ◽  
Praveen V. Vadlani
Keyword(s):  
Fossil Fuels ◽  
Process Intensification ◽  
Raw Material ◽  
Biomass Composition ◽  
Biomass Feedstocks ◽  
Renewable Biomass ◽  
Sustainability Criteria ◽  
Biomass Component ◽  
Biomass Resources ◽  
Multiple Challenges

Lignocellulosic biomass feedstocks are promising alternatives to fossil fuels for meeting raw material needs of processing industries and helping transit from a linear to a circular economy and thereby meet the global sustainability criteria. The sugar platform route in the biochemical conversion process is one of the promising and extensively studied methods, which consists of four major conversion steps: pretreatment, hydrolysis, fermentation, and product purification. Each of these conversion steps has multiple challenges. Among them, the challenges associated with the pretreatment are the most significant for the overall process because this is the most expensive step in the sugar platform route and it significantly affects the efficiency of all subsequent steps on the sustainable valorization of each biomass component. However, the development of a universal pretreatment method to cater to all types of feedstock is nearly impossible due to the substantial variations in compositions and structures of biopolymers among these feedstocks. In this review, we have discussed some promising pretreatment methods, their processing and chemicals requirements, and the effect of biomass composition on deconstruction efficiencies. In addition, the global biomass resources availability and process intensification ideas for the lignocellulosic-based chemical industry have been discussed from a circularity and sustainability standpoint.

scholarly journals A New Nanocomposite Packaging Based on LASiS-Generated AgNPs for the Preservation of Apple Juice

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 760
Author(s):  
Maria Chiara Sportelli ◽  
Antonio Ancona ◽  
Annalisa Volpe ◽  
Caterina Gaudiuso ◽  
Valentina Lavicita ◽  
...  
Keyword(s):  
Metal Ion ◽  
Chemical Characterization ◽  
Average Diameter ◽  
Biological Action ◽  
Metal Species ◽  
Ion Release ◽  
Bioactive Materials ◽  
Transmission Electron ◽  
Metal Ion Release ◽  
Bulk Chemical

Designing bioactive materials, with controlled metal ion release, exerting a significant biological action and associated to low toxicity for humans, is nowadays one of the most important challenges for our community. The most looked-for nanoantimicrobials are capable of releasing metal species with defined kinetic profiles, either by slowing down or inhibiting bacterial growth and pathogenic microorganism diffusion. In this study, laser ablation synthesis in solution (LASiS) has been used to produce bioactive Ag-based nanocolloids, in isopropyl alcohol, which can be used as water-insoluble nano-reservoirs in composite materials like poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Infrared spectroscopy was used to evaluate the chemical state of pristine polymer and final composite material, thus providing useful information about synthesis processes, as well as storage and processing conditions. Transmission electron microscopy was exploited to study the morphology of nano-colloids, along with UV-Vis for bulk chemical characterization, highlighting the presence of spheroidal particles with average diameter around 12 nm. Electro-thermal atomic absorption spectroscopy was used to investigate metal ion release from Ag-modified products, showing a maximum release around 60 ppb, which ensures an efficient antimicrobial activity, being much lower than what recommended by health institutions. Analytical spectroscopy results were matched with bioactivity tests carried out on target microorganisms of food spoilage.

Antifungal Effectiveness of Nanosilver Colloid against Rose Powdery Mildew in Greenhouses

2008 ◽  
Vol 135 ◽  
pp. 15-18 ◽  
Author(s):  
Hae Sic Kim ◽  
Hyun Suk Kang ◽  
Gyo Jin Chu ◽  
Hong Sik Byun
Keyword(s):  
Electron Microscopy ◽  
Powdery Mildew ◽  
Colloidal Solution ◽  
Physical Method ◽  
Average Diameter ◽  
Optical Microscope ◽  
Size Analysis ◽  
Large Area ◽  
Transmission Electron ◽  
Antifungal Effects

The antifungal effectiveness against rose powdery mildew using antimicrobial nanosilver colloidal solution was investigated. Double-capsulized nanosilver was prepared by chemical reaction of silver ion with aid of physical method, reducing agent and stabilizers. The average diameter of nanosilver was about 1.5 nm. They were highly stable and very well dispersive in aqueous solution. The Transmission electron microscopy and UV-vis spectrometer were used for measurements of size analysis and their stability, respectively. The nanosilver colloidal solution of concentration of 5000 ppm was diluted in 10 ppm of 500 kg and sprayed at large area of 3306 m2polluted by rose powdery mildew. The white rose powdery mildew fade out above 95 % after 2 days and was not recurred for a week. The antifungal effects were observed by an optical microscope and photographs.

Characterization of Al65.0Cu32.9Co2.1 Alloy Containing Nanofibres

2012 ◽  
Vol 186 ◽  
pp. 212-215
Author(s):  
Jacek Krawczyk ◽  
Włodzimierz Bogdanowicz ◽  
Grzegorz Dercz ◽  
Wojciech Gurdziel
Keyword(s):  
Electron Microscopy ◽  
Average Diameter ◽  
Chemical Compositions ◽  
X Ray ◽  
Transmission Electron ◽  
Orthogonal Set ◽  
T Phase ◽  
Terminal Area ◽  
Scanning Electron

Microstructure of terminal area of Al65Cu32.9Co2.1ingots (numbers indicate at.%), obtained via directional solidification was studied. Scanning Electron Microscopy, Transmission Electron Microscopy and X-ray powder diffraction were applied. Point microanalysis by Scanning Electron Microscope was used for examination of chemical compositions of alloy phases. It was found that tetragonal θ phase of Al2Cu stoichiometric formula was the dominate phase (matrix). Additionally the alloy contained orthogonal set of nanofibres of Al7Cu2Co T phase with the average diameter of 50-500 nm and oval areas of hexagonal Al3(Cu,Co)2H-phase, surrounded by monoclinic AlCu η1phase rim. Inside some areas of H-phase cores of decagonal quasicrystalline D phase were observed.

Tribological Behavior of Carbon Nanotubes as an Additive on Lithium Grease

2014 ◽  
Vol 137 (1) ◽  
Author(s):  
Alaa Mohamed ◽  
T. A. Osman ◽  
A. Khattab ◽  
M. Zaki
Keyword(s):  
Carbon Nanotubes ◽  
Arc Discharge ◽  
Average Diameter ◽  
Friction Reduction ◽  
Lithium Grease ◽  
X Ray ◽  
Transmission Electron ◽  
Boundary Film ◽  
Load Carrying ◽  
Worn Surface

Carbon nanotubes (CNTs) with 10 nm average diameter and 5 μm in length were synthesized by electric arc discharge. The morphology and structure of CNTs were characterized by high resolution transmission electron microscopy (HRTEM) and X-ray powder diffraction. The tribological properties of CNTs as an additive on lithium grease were evaluated with a four ball tester. The results show that the grease with CNTs exhibit good performance in antiwear (AW) and decrease the wear scare diameter (WSD) about 63%, decrease friction reduction about 81.5%, and increase the extreme pressure (EP) properties and load carrying capacity about 52% with only 1% wt. of CNTs added to lithium grease. The action mechanism was estimated through analysis of the worn surface with a scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The results indicate that a boundary film mainly composed of CNTs, Cr, iron oxide, and other organic compounds was formed on the worn surface during the friction process.

Preparation and properties of wet-spun microcomposite filaments from cellulose nanocrystals and alginate using a microfluidic device

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 5780-5793
Author(s):  
Ji-Soo Park ◽  
Chan-Woo Park ◽  
Song-Yi Han ◽  
Eun-Ah Lee ◽  
Azelia Wulan Cindradewi ◽  
...  
Keyword(s):  
Tensile Properties ◽  
Sodium Alginate ◽  
Calcium Chloride ◽  
Microfluidic Device ◽  
Cellulose Nanocrystals ◽  
Average Diameter ◽  
Coagulation Bath ◽  
Al Content ◽  
Orientation Index ◽  
Cacl2 Solution

Cellulose nanocrystals (CNCs) were wet-spun in a coagulation bath for the fabrication of microfilaments, and the effect of sodium alginate (AL) addition on the wet-spinnability and properties of the microcomposite filament was investigated. The CNC suspension exhibited excellent wet-spinnability in calcium chloride (CaCl2) solution, and the addition of AL in CNC suspension resulted in the enhancement of the wet-spinnability of CNCs. As the AL content increased from 3% to 10%, the average diameter of the microcomposite filament decreased, and its tensile properties deteriorated. The increased spinning rate caused an increase in the orientation index of CNCs, resulting in an improvement in the tensile properties of the microcomposite filament.

Sign in / Sign up

Export Citation Format

Share Document