scholarly journals Preparation and Characterization of Ultra-Fine Oil Palm Ash Powder by Ultrasonication and Alkaline Treatment for Its Evaluation as Reinforcing Filler in Natural Rubber

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 100
Author(s):  
Methakarn Jarnthong ◽  
Chutarat Malawet ◽  
Lusheng Liao ◽  
Puwang Li ◽  
Zheng Peng ◽  
...  

Ultra-fine oil palm ash (OPA) particles were successfully prepared using ultrasonication along with optimal chemical deagglomeration. The influence of chemical treatment by sodium hydroxide (NaOH) solution on the OPA particles was found to be an important factor in enhancing deagglomeration efficiency. The average particle size of the original OPA (41.651 μm) decreased remarkably more than 130 times (0.318 μm) with an obvious increase of Brunauer–Emmet–Teller (BET) surface area after treating the OPA with 3M NaOH, followed by ultrasonication for 30 min. The changes in particle size and surface morphology were investigated using transmission electron microscopy and scanning electron microscopy. Moreover, the chemical functional groups of the untreated and treated OPA showed different patterns of infrared spectra by the presence of sodium carbonate species owing to the effect of NaOH treatment. The incorporation of both untreated and treated OPA in natural rubber by increasing their loading can improve cure characteristics (i.e., reducing optimum cure time and increasing torques) and cure kinetic parameters (i.e., increasing the rate of cure and reducing activation energy). Nevertheless, the strength, degree of reinforcement, and thermal stability of treated OPA as well as wettability between treated OPA particles and NR were greater than that resulting from the untreated OPA.

2011 ◽  
Vol 415-417 ◽  
pp. 617-620 ◽  
Author(s):  
Yan Su ◽  
Ying Yun Lin ◽  
Yu Li Fu ◽  
Fan Qian ◽  
Xiu Pei Yang ◽  
...  

Water-soluble gold nanoparticles (AuNPs) were prepared using 2-mercapto-4-methyl-5- thiazoleacetic acid (MMTA) as a stabilizing agent and sodium borohydride (NaBH4) as a reducing agent. The AuNPs product was analyzed by transmission electron microscopy (TEM), UV-vis absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR). The TEM image shows that the particles were well-dispersed and their average particle size is about 5 nm. The UV-vis absorption and FTIR spectra confirm that the MMTA-AuNPs was stabilized by the carboxylate ions present on the surface of the AuNPs.


1997 ◽  
Vol 496 ◽  
Author(s):  
David J. Derwin ◽  
Kim Kinoshita ◽  
Tri D. Tran ◽  
Peter Zaleski

AbstractSeveral types of carbonaceous materials from Superior Graphite Co. were investigated for lithium ion intercalation. These commercially available cokes, graphitized cokes and graphites have a wide range of physical and chemical properties. The coke materials were investigated in propylene carbonate based electrolytes and the graphitic materials were studied in ethylene carbonate / dimethyl solutions to prevent exfoliation. The reversible capacities of disordered cokes are below 230 mAh / g and those for many highly ordered synthetic (artificial) and natural graphites approached 372 mAh / g (LiC6). The irreversible capacity losses vary between 15 to as much as 200 % of reversible capacities for various types of carbon. Heat treated cokes with the average particle size of 10 microns showed marked improvements in reversible capacity for lithium intercalation. The electrochemical characteristics are correlated with data obtained from scanning electron microscopy (SEM), high resolution transmission electron microscopy (TAM), X - ray diffraction (XRD) and BET surface area analysis. The electrochemical performance, availability, cost and manufacturability of these commercial carbons will be discussed.


2017 ◽  
Vol 263 ◽  
pp. 165-169
Author(s):  
Silvia Chowdhury ◽  
Faridah Yusof ◽  
Nadzril Sulaiman ◽  
Mohammad Omer Faruck

In this article, we have studied the process of silver nanoparticles (AgNPs) aggregation and to stop aggregation 0.3% Polyvinylpyrrolidone (PVP) was used. Aggregation study carried out via UV-vis spectroscopy and it is reported that the absorption spectrum of spherical silver nanoparticles were found a maximum peak at 420 nm wavelength. Furthermore, Transmission Electron Microscopy (TEM) were used to characterized the size and shape of AgNPs, where the average particle size is around 10 to 25 nm in diameter and the AgNPs shape is spherical. Next, Dynamic Light Scattering (DLS) were used, owing to observed size distribution and self-correlation of AgNPs.


2020 ◽  
Vol 20 (6) ◽  
pp. 3770-3779 ◽  
Author(s):  
Umar Farooq ◽  
Farheen Naz ◽  
Ruby Phul ◽  
Nayeem Ahmad Pandit ◽  
Sapan Kumar Jain ◽  
...  

This paper reports the attempt to develop an efficient heterostructure photocatalyst by employing SrZrO3 as ferroelectric substrate with deposited nanostructured CdS semiconductor on the surface. Primarily bare SrZrO3 and CdS nanoparticles were synthesized by using polymeric citrate precursor and co-precipitation routes, respectively. The chemical deposition technique was used to develop the CdS over the surface of the pre-synthesized SrZrO3 nanoparticles. The synthesized bare nanoparticles and their heterostructure were characterized by XRD which shows the formation of orthorhombic and face centred cubic (FCC) phases of SrZrO3 and CdS, respectively. TEM was used to estimate the morphology and particle size of as-synthesized nanoparticles, which shows the average particle size of 14, 24 and 25 nm for SrZrO3, CdS and SrZrO3/CdS, respectively. The BET surface area of SrZrO3, CdS and SrZrO3/CdS samples was found to be 299, 304 and 312 m2/g respectively. Methylene blue was used as model pollutant to determine the photocatalytic activity of the synthesized nanomaterials. The heterostructure shows an enhanced activity as compared to bare nanoparticles. Dielectric constant and dielectric loss of the nanoparticles was investigated as a function of frequency at room temperature and as a function of temperature at 500 kHz. The room temperature dielectric constant for SrZrO3, CdS and SrZrO3/CdS was found to be 13.2, 17.8 and 25.5 respectively at 100 kHz.


2016 ◽  
Vol 680 ◽  
pp. 198-202
Author(s):  
Chao Wang ◽  
Si Qin Zhao ◽  
S. Asuha

In this paper, a series of mesoporous TiO2 photocatalyst were prepared by hydrothermal method using block copolymer P123 as template and Ti (OBu)4 as titanium source. The microstructure and spectroscopy performance of the prepared TiO2 were characterized by means of XRD, SEM, TEM, BET, and BJH analysis, and the photocatalytic activity of mesoporous TiO2 were examined by measuring the photodegradation of methyl orange , then discussed the best prepared conditions of mesoporous TiO2 photocatalyst. The results showed that the products were all anatase mesoporous TiO2 nanopowder, the average particle size is about 7nm and all have the Langmuir type IV pore structure. The best prepared condition: hydrothermal temperature is 160°C, hydrothermal time is 24h, mesoporous TiO2 photocatalyst has the BET surface area of 146m2/g , it’s photocatalytic degradation rate is 97.07% in an hour.


Author(s):  
B. Graham ◽  
R.F. Klie

In the hope of optimizing the Fischer-Tropsch mechanism to produce cleaner ethanol, the catalyst- promoter interaction between rhodium and manganese was examined by transmission electron microscopy. Three samples were analyzed on a carbon nanotube (CNT) substrate with 3 wt% rhodium (3%Rh/CNT), 1% manganese with 3 wt% rhodium (1%Mn/3% Rh/CNT), and 2% manganese with 3 wt% rhodium (2% Mn/3% Rh/CNT). The average particle size were found to be (1.9 ± 0.6) nm, (2.1 ± 0.5) nm, and (3.2 ± 0.6) nm, respectively. An increase in particle size indicates that the rhodium and manganese are interacting. The lattice parameter for rhodium were also determined to be (4.1 ± 0.1) Å, (4.2 ± 0.1) Å, and (3.8 ± 0.1) Å, respectively. The decrease in lattice parameter in the 2%Mn/3%Rh/CNT sample was most likely due to a change in the crystal structure of the rhodium particles as a result of the interaction between the manganese and rhodium.


2007 ◽  
Vol 121-123 ◽  
pp. 97-100
Author(s):  
D. Yang ◽  
Ming Fen Wen ◽  
Ch.L. Song ◽  
Jian Chen ◽  
Yong Wan Gu

Herein mesoporous CeO2 with high thermal stability was synthesized via a new hydroxycarbonates based hydrothermal threatment approach in present of hexadecyltrimethylammonium bromide (CTAB). IR and XRD prove the coexistence of hydroxycarbonate cerium and CTAB in precursors. TEM micrographs show that non-ordered pore structure is formed in the product, and average particle size of 20 nm is obtained even after calcined at 1173 K. BET results exhibit that the pore structure is stable when the calcination temperature is below 923 K. However, While calcinated at 1173 K, the average particle size is 20 nm, the BET surface area and pore volume can remain as high as 31.07 m2/g and 0.21 cm3 g-1.


2018 ◽  
Vol 34 (4) ◽  
pp. 1817-1823
Author(s):  
I. Nengah Simpen ◽  
I. Made Sutha Negara ◽  
Ni Made Puspawati

Heterogeneous nanocatalyst of biohydroxyapatite-lithium (HA-Li) has been prepared through modification of HA extracted from bovine bone waste with Li at various calcination temperatures (400-700oC). Characterizations of the heterogeneous catalysts were including surface acidity-basicity, functional groups, BET surface area, particle size, and surface morphology. Optimization of catalyst ratios (1-7%) with the best characterization was applied for converting Malapari seed oil (Milletia pinnata L.) to biodiesel. The characterization results showed that HA-Li catalyst calcinated at 600oChad the highest surface basicity and Lewis acid sites revealing specific functional group of O-Li at wavenumber of 1612.49 cm-1. BET surface area of HA-Li catalyst decreased with increased average particle size. SEM analysis suggested that morfology of catalysts formed stack of agglomerates. The highest yield of biodiesel obtained on a catalyst ratio of 5% was 88.16%. GC-MS analysis showed 10 peaks, and 5 of the peaks exhibiting the highest percentage area were identified as methyl oleic, methyl palmitic, methyl erusic, methyl stearic, and methyl linoleic.


2018 ◽  
Vol 24 (8) ◽  
pp. 5640-5644
Author(s):  
B Sreenivasulu ◽  
S. Venkatramana Reddy ◽  
P. Venkateswara Reddy

Pure ZnS and 3 mol% of Ni doped ZnS nano powders are prepared by chemical co-precipitation method. Properties of ZnS: Ni2+ nanoparticles are studied by X-ray diffraction Spectra (XRD), Raman spectroscopy (RS), Photoluminescence (PL), Absorption Spectra, Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX), Transmission electron microscopy (TEM) and Vibrating sample magnetometer (VSM). From XRD data, it conform the structure of ZnS, and particle size of pure and Ni doped ZnS data indicates the incorporation of Ni2+ in ZnS nanocrystal lattice. Raman spectra for pure and Ni doped samples exhibited vibrational modes confirm the structure of ZnS. Photoluminescence spectra reveal that the emission peaks are in UV and visible regions; this is confirming the absorption spectra. SEM micrographs show spherical morphology, and chemical compositions of samples are in stoichiometric proportions. TEM micro graphs show the spherical surface morphology and average particle size for pure and Ni2+ doped nanoparticles are in the range of 2–3 nm, this is good agreement with XRD results. M–H curves from VSM show room temperature ferromagnetism.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1726
Author(s):  
Guoyu Tian ◽  
Xiuhong Zhong ◽  
Xuehai Wu ◽  
Zhaojiang Wang

The present work describes the preparation of nano-lignin particles from calcium lignosulfonate (CL). The nano-lignin was fabricated from colloidal lignin–polyacrylamide complexes via self-assembly. The sizes of the nano-lignin particles were examined by dynamic light scattering (DLS) and scanning electron microscopy (SEM). The results indicated that the average particle size of the prepared nano-lignin was approximately 100 nm. In addition, the obtained nano-lignin exhibited enhanced fluorescence intensity when compared with the original lignin, which might represent a potential application of this nano-particle product.


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