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2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aasma Saeed ◽  
Muhammad Asif Hanif ◽  
Haq Nawaz ◽  
Rashad Waseem Khan Qadri

AbstractThe present study was undertaken with aims to produced catalyst loaded on low-cost clay supports and to utilize plum waste seed oil for the production of biodiesel. For this purpose, Bentonite–potassium ferricyanide, White pocha-potassium ferricyanide, Granite-potassium ferricyanide, Sindh clay-potassium ferricyanide, and Kolten-potassium ferricyanide composites were prepared. Transesterification of plum oil under the different conditions of reactions like catalysts concentrations (0.15, 0.3 and 0.6 g), temperature (50, 60, 70 and 80 °C), reaction time (2, 4 and 6 h) and oil to methanol ratio (1:10) was conducted. The maximum biodiesel yield was recorded for Bentonite–potassium ferricyanide composite. This composite was subjected to calcination process to produce Calcinized bentonite–potassium ferricyanide composite and a further improvement in biodiesel amount was recorded. The fuel quality parameters of all biodiesel samples were in standard range. Gas chromatographic mass spectrometric analysis confirmed the presence of oleic and linoleic acids in the plum seed oil. The characterization of composite was done using FTIR, SEM and EDX. Two infrared bands are observed in the spectrum from 1650 to 1630 cm−1 indicates that the composite materials contained highly hydrogen bonded water. The presence of surface hydroxyls groups can also be confirmed from FTIR data. SEM image clearly show the presence of nano-rods on the surface of Granite-potassium ferricyanide and Kolten-potassium ferricyanide composites. Another interesting observation that can be recorded from SEM images is the changes in surface characteristic of Bentonite–potassium ferricyanide composite after calcination (at 750 °C, 1 atm for 4 h). Calcinized bentonite–potassium ferricyanide composite found to contain more nano rod like structures at its surface as compared to Bentonite–potassium ferricyanide composite which contained spherical particles. EDX data of Bentonite–potassium ferricyanide composite and Calcinized bentonite–potassium ferricyanide composite show that after calcination carbon and oxygen was reduced. The other lost volatile compounds after calcination were of Na, Mg, Al, Si, and S. The XRD spectrum of pure bentonite showed the average crystal size of 24.46 nm and calcinized bentonite of 25.59 nm. The average crystal size of bentonite and potassium ferricyanide composite and its calcinized form was around 33.76 nm and 41.05 nm, respectively.


2021 ◽  
Vol 13 (5) ◽  
pp. 794-802
Author(s):  
Sami-ullah Rather ◽  
Abdulrahim Ahmad Al-Zahrani ◽  
Usman Saeed ◽  
O. M. Lemine ◽  
Saad S. A. Al-Shahrani ◽  
...  

Aluminum–nickel ferrite nanostructure with a nominal composition of NiFe2-xAlxO4 (0 < x < 0.9) was synthesized by heat treatment process by employing polyvinylpyrrolidone (PVP) as a capping operator. The effects of Al3+ substitution on structural, morphological, quantitative, qualitative and magnetic properties were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron microscopy (XPS) and vibrating-sample magnetometry (VSM). Single-phase inverse spinel structure and decrease in average crystal size as Al concentration increases was acknowledged by XRD and EDX characterization. The decrease in average crystal size as Al3+ ions content increases is associated with structural effects of overall crystal size of nanostructure. The development of a thermally stable nickel ferrite above 500 °C was detected by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. The magnetic hysteresis loop measurements at room temperature (RT) with an ultimate tested magnetic field of 1.8 T shows both saturation and remnant magnetization decreases as content of Al3+ ions substitution increases. The decrease in overall magnetization is due to spin non-collinearity, weakening of magnetocrystalline anisotropy and weak super-exchange interactions.


2019 ◽  
Vol 4 (3) ◽  
pp. 68-72
Author(s):  
Ana Maria Herrera ◽  
Godofredo García ◽  
Erick Gastellóu ◽  
Fabiola Nieto ◽  
Rafael García ◽  
...  

Hexagonal nanocrystals into Al0.2Ga0.8N and Al0.6Ga0.4N powders via pyrolysis from an organometallic compound, followed by a nitridation process in ammonia flow at 1000 °C for two hours were obtained. X-ray diffraction patterns demonstrated a shift towards greater angles to the right for the AlGaN powders with respect to GaN powders, this shift could indicate the formation of the AlGaN powders. Scanning electron microscopy micrographs showed the obtaining from semi-plates of porous appearance for the Al0.2Ga0.8N powders until well-defined plates for the Al0.6Ga0.4N powders. High resolution transmission electron microscopy micrographs demonstrated the presence of hexagonal nanocrystals into Al0.2Ga0.8N powders with an average crystal size of 10.3 nm, while that for the Al0.6Ga0.4N powders an average crystal size of 9.7 nm was observed. UV-visible spectra showed a transmittance cut-off for the Al0.2Ga0.8N powders of 3.71 eV (334.2 nm) and a transmittance cut-off of 4.53 eV (273.7 nm) for the Al0.6Ga0.4N powders.


2018 ◽  
Vol 7 (4.37) ◽  
pp. 22 ◽  
Author(s):  
Assist. Prof. Ali S. Ali ◽  
Alaa J. Mohammed ◽  
Haider R. Saud

The powder of TiO2/α-Al2O3 nanocomposite for Sonocatalysis decolorisation was successfully achieved in the Hydrothermal autoclave reaction for 6 hours and completely crystallized into Anatase phase at temperature of 220oC which more lower than normal required calcination temperature 500oC. The TiO2/α-Al2O3 nanoparticles examined using FT-IR, SEM, TGA, X-ray diffraction studies( XRD), The results indicate the formation of nanocomposite with tetragonal Anatase phase and average crystal size of 21.4nm for TiO2/α-Al2O3 while the average crystal size of 8.1nm for Al2O3, which are calculated according to Scherrer’s equation. This powder was mixed with methylene blue to study the effect of nanocomposite on it, the prepared nanocomposite show highly decolorisation percentage of methylene blue solution. 


2018 ◽  
Vol 31 (1) ◽  
pp. 180 ◽  
Author(s):  
Mohammed H. Abdul Latif ◽  
Yasir Fathi Mahmood

Because of the conservation problems causes by the existence of water hyacinth (W.H) as an watery plant in water bodies of Iraq, our study aimed to make  use of (W.H) by isolation of microcrystalline cellulose, and a new method of preparation of Nano crystalline cellulose. Microcrystalline cellulose was produced using base bleaching method by sodium hypochlorite [NaOCl] to remove unorganized region of cellulose and lignin to create particles comprising of micro crystal and preparing of Nano crystalline cellulose from microcrystalline cellulose by acid hydrolysis and ultrasonic treatment. The Nano crystalline and microcrystalline cellulose characterized by AFM, FTIR, XRD and TGA. FT-IR spectra of microcrystalline cellules and Nano crystalline cellulose show peaks at (1076.28, 1058.92) cm-1 and (1118.71, 1112.93) cm-1 refer to the stretching vibration of   C–O and stretching vibration intermolecular ester bonding.         The AFM image shows that isolated microcrystalline cellulose have a diameter of (141.37 nm) and the prepared Nano crystalline have a diameter of (87.39 nm). The Thermo gravimetric analysis of cellulose showed a high decomposition temperature at (283°C) for microcrystalline cellulose and (253)°C for Nano crystalline cellulose .The thermal stability of microcrystalline cellulose was more than Nano crystalline cellulose XRD result possessed a segal crystallinity index of 92.8 % and a average crystal size of 41.7 A ° for Nano crystalline cellulose and a Segal Crystallinity Index of 86.4 % and a average crystal size of 55.3°A    of microcrystalline cellulose.   


2018 ◽  
Vol 23 (1) ◽  
Author(s):  
Francisco Marcone Lima ◽  
Felipe Mota Martins ◽  
Paulo Herbert França Maia Júnior ◽  
Ana Fabíola Leite Almeida ◽  
Francisco Nivaldo Aguiar Freire

ABSTRACT The materials sizing in nano-scale is a challenge to be overcome, because the size determined by various methods differ. In order to shed light about the nanomaterials sizing, a modified Scherrer's equation was applied to estimate more accurately the nanostructured titanium dioxide crystal size. The manufactured titanium dioxide-nanostructured powder with nominal average size about 21nm was used as the reference standard to determine the accurate of modified equation. From X-ray diffraction data, an average crystal size about 20.63 nm was achieved for unheated sample. To establish a relation between the result obtained with modified Scherrer's equation and the nominal average crystal size, a statistical treatment and a comparative assessment were performed. The average absolute divergence does not exceed 0.70 nm. The value of crystal size determined from X-ray data was in good agreement with that informed by the supplier. Additionally, the behavior of sample was studied as a function of temperature.


2017 ◽  
Vol 899 ◽  
pp. 77-82
Author(s):  
Davi Batista Quintino ◽  
Ricardo Amâncio Malagoni

Through yield and Sauter mean diameter, the sucrose crystallization was studied in vibrated bed equipment, in which, supersaturation degree, dimensionless vibration number and crystallization time were independent variables. A central composite design with seventeen trials was performed in order to ascertain the influence of each variable in both responses, the crystallization temperature and the amount of seeds were kept constant. The crystallization vibration system differs from the usual configuration, consisting of two perforated discs made of stainless steel, one loop and three aluminum rings. By canonical analysis, it was obtained the operating condition which maximizes the yield and average crystal size. Surface responses were also obtained according to the relevance of each variable, in which were evidenced the high supersaturation and vibration influence for both factors, the high quadratic term of all variables on the crystal yield, and also highlights the great interaction between supersaturation and the dimensionless vibration number.


2016 ◽  
Vol 12 (2) ◽  
pp. 177-182 ◽  
Author(s):  
S. Samnur ◽  
H. Husain ◽  
A. Zulfi ◽  
E. H. Sujiono

This research aims to prepare powder of nickel slag from furnace machine, identify, and analyze of the elements or compounds containing in the sample. The data retrieval was done with the analysis of elemental composition, phase microstructures, crystal size, distribution, and composition mapping of the samples by using XRD, Rigaku Miniflex II, and SEM-EDS, Tescan Vega-3. XRD result indicates that the formation which the similar to amorphous phase was identified and the formation at peak 2? = 28.01 is identified as the low quartz (SiO2). FWHM 0.18 was obtained using microcal origin 6.0 and average crystal size 53.37 nm was obtained by applying Scherer equation. SEM results show average grain size of samples which is less than 1?m and maximum to 4?m. Based on EDS result, the main constituent elements are Si 32.86 wt%, Mg 19.40 wt%, and Fe 32.03 wt%, respectively.Penelitian ini bertujuan untuk menyiapkan bubuk slag nikel yang berasal dari furnace, yang dilanjutkan dengan mengidentifikasi dan menganalisis unsur atau paduan yang terkandung di dalamnya. Data diperoleh dengan melakukan analisis terhadap komposisi unsur, fasa mikrostruktur, ukuran Kristal, distribusi dan komposisi paduan dari sampel bubuk slag nikel furnace dengan menggunakan XRD tipe Rigaku Miniflex II dan SEM-EDS tipe Tescan Vega-3. Hasil analisis XRD menunjukkan bahwa formasi yang dihasilkan menyerupai fase amorf dan formasi yang terbentuk pada puncak 2? = 28.01 diidentifikasi sebagai low quartz (SiO2). Dengan menggunakan microcal origin 6.0 diperoleh FWHM 0.18 dan menggunakan persamaan Scherer diperoleh rata-rata ukuran kristal 53.37 nm. Hasil pengukuan SEM menunjukkan bahwa rata-rata ukuran butir dari sampel bubuk slag nikel furnace bervariasi antara minimal 1?m dan maksimum 4 ?m. Berdasarkan pengukuran EDS diperoleh secara berturut-turut bahwa unsur utama penyusun paduan slag nikel furnace adalah Si 32.86 wt%, Mg 19.40 wt%, dan Fe 32.03 wt%.


2014 ◽  
Vol 609-610 ◽  
pp. 165-168
Author(s):  
R.Y. Li ◽  
H.L. Yang ◽  
H.H. Yan ◽  
X.H. Wang ◽  
X.J. Li

The Al2O3 is synthesized by detonation of mixed explosive, prepared by mixing RDX and aluminum hydroxide named as precursor of thermal decomposition. The production of detonation is analysed by XRD, TEM and DTA/TG. The curve of XRD indicates that the production are (α+γ)-Al2O3. The average crystal size of Al2O3 is 126nm calculated by the Scherrer equation. The photographs of TEM show that all granules of Al2O3 are spherical, and the average size of granule is 1000nm. The visible exothermic or endothermic peak does not appear on the curve of DTA from 50 to 1300 degree Centigrade. The curve of TG indicates that the production of detonation generates 12% weight loss from 50 to 1300 degree Centigrade.


2012 ◽  
Vol 578 ◽  
pp. 99-104
Author(s):  
Yang Lin Liu ◽  
Xue Chen Duan ◽  
Shu Yun Liu ◽  
Yan Yan Liu

Mesoporous TiO2 microspheres were prepared by Ultrasonic-Hydrothermal Process with tetrabutyltitanate as titanium resource and octadecylamine as template. The effects of temperature and time of hytrothermol process, and calcination temperature on the structure had been investigated via XRD,SEM,TEM.The results indicated it will be better hythrothermol treating 20h at 120°Cand then heat-treating 4h at 400°C. A high surface area of 261.7 m2/g and pore volume of 0.28cm3/g was obtained in the corresponding sample with quite narrow distribution,and centering at 4.3nm in diameter.TiO2 frame was highly crystallized, showed the characteristic of pure anataste, with average crystal size of 10.0nm. The as-prepared sample possess a morphology of microspheres with diameter about 100-300nm.The photocatalytic activity was valuated by photodegradation of methly orange. The resultes indicated 99.79% of methly orange in the solution was removed after 30min photocatalytic treatment.


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