scholarly journals Preparation of Microcrystalline Cellulose from Oil Palm Empty Fruit Bunch Fibre Using Steam-Assisted Acid Hydrolysis

2021 ◽  
Vol 81 (1) ◽  
pp. 88-98
Author(s):  
Fatiha Ismail ◽  
Nur Eliyanti Ali Othman ◽  
Noorshamsiana Abdul Wahab ◽  
Fazliana Abdul Hamid ◽  
Astimar Abdul Aziz
Keyword(s):  
Thermal Stability ◽  
Acid Hydrolysis ◽  
Microcrystalline Cellulose ◽  
Crystallinity Index ◽  
Steam Treatment ◽  
Empty Fruit Bunch ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Stability Of ◽  
Scanning Electron

The isolation of microcrystalline cellulose (MCC) from empty fruit bunch fibre (EFB-fibre) using acid hydrolysis through steam treatment (autoclave) followed by ultrasonication has been successfully established. The important parameter studied was the concentration of sulphuric acid (5%, 15% and 25%) at variable fixed reaction time and temperature. The resulting MCC was characterized using FTIR, TGA, XRD and SEM. FTIR transmission at 1163 cm-1 confirmed that the structure of cellulose was retained after undergoing acid hydrolysis. Thermal stability of MCC increased after being treated with H2SO4, which was determined using TG analysis. The morphological features were identified using Scanning Electron microscope (SEM), which showed the diameters of MCC to be in the range of 10 to 200 µm. The structural property of MCC was studied using X-ray diffraction (XRD) and the results showed that the MCC produced has crystallinity index of 72%. The results revealed that the parameters used tend to influence the physicochemical properties of MCC produced. Therefore, the MCC isolated from EFB fibres will be used as precursor for future EFB derived nanocellulose as well as a promising subject in nanocomposite research.

Preparation of Polyaniline/SiO2 Composites by Modified Silica Using Succinic Acid

2012 ◽  
Vol 535-537 ◽  
pp. 149-153 ◽  
Author(s):  
Er Yuan Li ◽  
Xiu Feng Wang ◽  
Xue Zhi Wang ◽  
Hao Wang
Keyword(s):  
Thermal Stability ◽  
Succinic Acid ◽  
X Ray Diffraction ◽  
Modified Silica ◽  
X Ray ◽  
Surface Character ◽  
Ft Ir ◽  
Thermal Stability Of ◽  
Scanning Electron ◽  
Ft Ir Spectroscopy

Polyaniline/SiO2 composites were prepared by the SiO2 particles whose surface character was modified by succinic acid. The composites were characterized by Fourier transform infrared (FT–IR) spectroscopy, X–ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM). The results demonstrated that the thermal stability of PANI had improved.

The Hydro-Thermal Stability of Hornblende Syenite in NaOH Solution

2014 ◽  
Vol 633 ◽  
pp. 230-233
Author(s):  
Cheng Zeng ◽  
Jing Yang ◽  
Hong Wen Ma ◽  
Chang Jiang Liu
Keyword(s):  
Thermal Stability ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Crystal Morphology ◽  
X Ray Diffraction ◽  
Solid Samples ◽  
X Ray ◽  
Naoh Solution ◽  
Thermal Stability Of ◽  
Scanning Electron

The microcline powder, which collected from the hornblende syenite from Anhui, China, was treated by NaOH solution at 250 °C for 2-6h. The solid samples were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD shows that the main solid sample is hydroxycancrinite. The images observed by SEM indicate that the crystal morphology of the hydroxycancrinite can be presented as hexagonal cylindrical when it reacted with 4.17M NaOH at 250 °C for 6h.

scholarly journals Influence of Strong Acid Hydrolysis Processing on the Thermal Stability and Crystallinity of Cellulose Isolated from Wheat Straw

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Chemar J. Huntley ◽  
Kristy D. Crews ◽  
Mohamed A. Abdalla ◽  
Albert E. Russell ◽  
Michael L. Curry
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Scanning Electron Microscopy ◽  
Acid Hydrolysis ◽  
Wheat Straw ◽  
Cellulose Fibers ◽  
Drying Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

Cellulose extractions from wheat straw via hydrochloric, nitric, and sulfuric acid hydrolysis methods were carried out. X-ray diffraction spectral analyses reveal that depending on the acid conditions used the structure of the cellulose exhibited a mixture of polymorphs (i.e., CI and CIII cellulose phases). In addition, the percent crystallinity, diameter, and length of the cellulose fibers varied tremendously as determined by X-ray diffraction and scanning electron microscopy. Thermal gravimetric analysis measurements revealed that the thermal stability of the extracted cellulose varied as a function of the acid strength and conditions used. Scanning electron microscopy analysis revealed that the aggregation of cellulose fibers during the drying process is strongly dependent upon the drying process and strength of the acids used.

Structure and Thermal Stability of Sugarcane Bagasse Cellulose Regenerated from Dialkylphosphate Ionic Liquids

2013 ◽  
Vol 800 ◽  
pp. 106-110 ◽  
Author(s):  
Meng Wang ◽  
Li Hong Cui ◽  
Ji Hua Li ◽  
Xiao Yi Wei ◽  
Fei Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Sugarcane Bagasse ◽  
Structural Modification ◽  
Regenerated Cellulose ◽  
X Ray Diffraction ◽  
X Ray ◽  
Downstream Processes ◽  
Thermal Stability Of ◽  
Scanning Electron

A phosphate-based ionic liquid, 1-ethyl-3-methylimidazolium diethylphosphate ([EMI[DE), was synthesized and used to dissolve sugarcane bagasse cellulose under microwave radiation. The original and regenerated cellulose were both characterized by X-ray diffraction, infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. The results showed that cellulose had a more porous and less crystalline structure after regeneration, whereas chemical composition had no change. Thermal stability of the regenerated cellulose was somewhat lower, corresponding to the decreased crystallinity. In short, the treatment with [EMI[DE led to desirable structural modification on sugarcane bagasse cellulose via physical process. This is of great benefit to the subsequent downstream processes, such as enzymatic hydrolysis and ethanol fermentation.

A Study of the Effect of Reaction Time on the Preparation of Zirconium Based UiO-66 MOF

2021 ◽  
Vol 897 ◽  
pp. 57-62
Author(s):  
Omneya A. Koriem ◽  
Ahmed H. El-Shazly ◽  
Marwa F. El-Kady
Keyword(s):  
Thermal Stability ◽  
Reaction Time ◽  
Solvothermal Method ◽  
Metal Organic Framework ◽  
High Water ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Organic ◽  
Thermal Stability Of ◽  
Scanning Electron

UiO-66 is a zirconium-based metal organic framework (MOF). It was synthesized and used by researchers due to its high water, chemical and thermal stability. The mentioned reasons in addition to other excellent properties made them a highly competitive materials for a variety of industrial problems. This study investigates the effect of the reaction time on the characteristics of the prepared UiO-66 nanoparticles. UiO-66 was synthesized by the solvothermal method and the reaction was left to take place for 18, 21 and 24 hours. UiO-66 was characterized using X-ray Diffraction (XRD) and Fourier-Transform Infrared (FTIR), the results showed that it has the same patterns and functional groups of the previously reported UiO-66. In addition, Scanning Electron Microscopy (SEM) was used to confirm the morphology of UiO-66. The smallest particle size around 200 nm was obtained at 18 hours. To investigate the thermal stability of the prepared UiO-66, Thermogravimetry analysis (TGA) was conducted. The results matched well with the literature and confirm that UiO-66 is thermally stable up to 500°C.

Formation and Stability of NI(PT) Silicide on (100)SI and (111)SI

1999 ◽  
Vol 564 ◽  
Author(s):  
D. Mangelinck ◽  
J. Y. Dai ◽  
S. K. Lahiri ◽  
C. S. Ho ◽  
T. Osipowicz
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Scanning Electron Microscopy ◽  
X Ray Diffraction ◽  
Rutherford Back Scattering ◽  
Kinetics And Thermodynamics ◽  
X Ray ◽  
Back Scattering ◽  
Thermal Stability Of ◽  
Scanning Electron

AbstractThe effect of a small amount of Pt (5 at.%) on the thermal stability of NiSi film on (100)Si and (111 )Si has been investigated. Rutherford back scattering, Scanning Electron Microscopy, and X-ray diffraction have been used to study the formation, microstructure and orientation of the silicide. The addition of platinum results in increasing the disilicide nucleation temperature to 900°C and thus leads to a better stability of NiSi at high IC processing temperatures. The presence of Pt also induced a texture of the NiSi film both on (11 1)Si and (100)Si. The increase in thermal stability is explained in terms of nucleation controlled reaction concept and should open new possibilities for the use of NiSi in self aligned silicidation. The redistribution of Pt in the silicide is examined and explained in terms of kinetics and thermodynamics considerations. The addition of Pt also increases the temperature of agglomeration of NiSi.

Flammability and Thermal Degradation of PMMA/Graphene Composites

2014 ◽  
Vol 910 ◽  
pp. 31-34
Author(s):  
Zheng Zhou Wang ◽  
Shao Hong Xu ◽  
Li Xin Wu ◽  
Dong Xian Zhuo
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Thermal Degradation ◽  
Cone Calorimeter ◽  
Pure Pmma ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Heat Release Rate ◽  
Thermal Stability Of ◽  
Scanning Electron

Graphene nanoplatelets (GNP) were prepared by ball milling, and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). PMMA/GNP composites were produced by a melt process. The flammability of PMMA/GNP composite was evaluated by the cone calorimeter (Cone) and thermal degradation of the composite by thermogravimetric analyses (TGA). Cone data indicate that the incorporation of 1% GNP leads to a 12% reduction in the peak heat release rate compared to pure PMMA. The TG results show that the addition of small amount of GNP (1%) can improve thermal stability of PMMA.

Combustibility and Thermal Degradation of PS/IFR/Graphene Composites

2014 ◽  
Vol 687-691 ◽  
pp. 4295-4298
Author(s):  
Jian Wei Yang ◽  
Zheng Zhou Wang ◽  
Li Xin Wu ◽  
Dong Xian Zhuo
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Thermal Degradation ◽  
Cone Calorimeter ◽  
Flame Retardants ◽  
X Ray Diffraction ◽  
X Ray ◽  
Peak Heat Release Rate ◽  
Thermal Stability Of ◽  
Scanning Electron

Graphene nanoplatelets (GNP) were prepared by ball milling, and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). PS/GNP composites were produced by a melt process. The flammability of PS/GNP composite was evaluated by the cone calorimeter (Cone) and thermal degradation of the composite by thermogravimetric analyses (TGA). Cone data indicate that the incorporation of 1% GNP leads to a 28% reduction in the peak heat release rate (PHRR) compared to pure PS. There is an synerhistic effect between intumesent flame retardants and GNP in a decrease in PhRR in PS. The incorporation of small amount of GNP can improve thermal stability of PS.

scholarly journals Improvement of the thermal stability of dendritic silver-coated copper microparticles by surface modification based on molecular self-assembly

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Tae Hyeong Kim ◽  
Hyeji Kim ◽  
Hyo Jun Jang ◽  
Nara Lee ◽  
Kwang Hyun Nam ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Photoelectron Spectroscopy ◽  
Self Assembly ◽  
Electrically Conductive ◽  
X Ray ◽  
Alkyl Chains ◽  
Conductive Film ◽  
Initial Resistance ◽  
Thermal Stability Of ◽  
Scanning Electron

AbstractIn the study reported herein, silver-coated copper (Ag/Cu) powder was modified with alkanethiols featuring alkyl chains of different lengths, namely butyl, octyl, and dodecyl, to improve its thermal stability. The modification of the Ag/Cu powders with adsorbed alkanethiols was confirmed by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Each powder was combined with an epoxy resin to prepare an electrically conductive film. The results confirmed that the thermal stability of the films containing alkanethiol-modified Ag/Cu powders is superior to that of the film containing untreated Ag/Cu powder. The longer the alkyl group in the alkanethiol-modified Ag/Cu powder, the higher the initial resistance of the corresponding electrically conductive film and the lower the increase in resistance induced by heat treatment.

Formation and Thermal Stability of Nd0.32Y0.68Si1.7 Layers Formed by Channeled Ion Beam Synthesis

1998 ◽  
Vol 514 ◽  
Author(s):  
M. F. Wu ◽  
A. Vantomne ◽  
S. Hogg ◽  
H. Pattyn ◽  
G. Langouche ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Ion Beam ◽  
Hexagonal Structure ◽  
Orthorhombic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Good Crystalline Quality ◽  
Ion Beam Synthesis ◽  
Thermal Stability Of

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.

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