Effects of Synthesis Parameters on Hydrothermal Synthesis of NaA Zeolite

In this research, NaA zeolite samples were synthesized from aluminosilicate solution through hydrothermal method. The effects of different parameters such as the SiO2/Al2O3, OH-/Si and H2O/Na2O molar ratios of the initial gel solution, crystallization time and temperature on the crystallinity and morphology of the synthesized zeolites were investigated. The final products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser particle size analyzer. The experiment results indicated that the SiO2/Al2O3 molar ratio had influence on morphology and size of the synthesized zeolites, the optimum range of SiO2/Al2O3 molar ratio for synthesizing NaA zeolite was 1.5-2. Alkalinity (OH-/Si and H2O/Na2O molar ratio) had a significant effect on particle sizes of the synthesized zeolites, the higher the alkalinity, the smaller the crystal particle size. In addition, it was found that crystallization temperature during hydrothermal treatment played an important role in reducing the over all reaction time. The crystallization time had effect on the crystallinity of the synthesized zeolites. Finally, the optimum synthesis parameters can be proposed in order to synthesize NaA zeolite with desirable particle size, crystallinity and morphology.

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Role of Synthesis Parameters on Structural and Electrical Properties of M-Type Hexa-Ferrites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.510-511.201 ◽

2012 ◽

Vol 510-511 ◽

pp. 201-205

Author(s):

G. Asghar ◽

S. Nasir ◽

M.S. Awan ◽

G.H. Tariq ◽

M. Akram ◽

...

Keyword(s):

Particle Size ◽

Diffraction Analysis ◽

Precipitation Method ◽

Molar Ratio ◽

Narrow Particle Size Distribution ◽

X Ray Diffraction ◽

Phase Purity ◽

X Ray ◽

Volume Rate ◽

Synthesis Parameters

Phase purity, particle size and its distribution contributes a lot to the physical properties of M-type hexa-ferrites. These parameters are strongly influenced by the variation in synthesis parameters. In the present work, effect of synthesis parameters such as molar ratio (Fe/Sr) and volume rate of addition of precipitating agent on M-type hexa-ferrite (SrFe12O19) prepared by co-precipitation method have been investigated systematically. The molar ratio (Fe/Sr) in SrFe12O19was varied as 12, 11, 10, 09, and 08. X-ray diffraction analysis revealed that molar ratio does not affect the phase purity. X-ray diffraction analysis of the samples prepared with different volume rate of addition of precipitating agent indicated that phase purity and micro-structural properties of SrFe12O19are greatly influenced by the above synthesis parameter. High volume rate of addition of precipitating agent resulted in high phase purity, smaller particle size, and narrow particle size distribution.

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Konduktivitas Apatit Lantanum Silikat La9.33Si6O26 Hasil Sintesis Hidrotermal dengan Mineraliser NaOH dan KOH

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.14.1.8468.1-15 ◽

2018 ◽

Vol 14 (1) ◽

pp. 1

Author(s):

Atiek Rostika Noviyanti ◽

Dani Gustaman Syarif ◽

Riansyah Amynurdin ◽

Iwan Hastiawan ◽

Iman Rahayu ◽

...

Keyword(s):

Particle Size ◽

Solid Oxide Fuel Cells ◽

Solid Oxide ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Particle Size Analyzer ◽

Lanthanum Silicates ◽

Lanthanum Silicate ◽

Apatite Type

Apatit lantanum silikat banyak digunakan sebagai elektrolit pada sel bahan bakar padatan (SOFC). Beberapa oksida apatit lantanum silikat La9.33Si6O26 telah disintesis dengan metode hidrotermal guna mengamati pentingnya peranan mineraliser terhadap karakternya. Penelitian ini bertujuan untuk mengetahui pengaruh jenis dan konsentrasi mineraliser terhadap kristalinitas, ukuran partikel dan hubungannya dengan sifat konduktivitas oksida apatit lantanum silikat. Struktur, ukuran partikel dan konduktivitas oksida apatit masing-masing dikarakterisasi dengan XRD, PSA dan spektroskopi impedansi. Oksida apatit lantanum silikat diperoleh dengan melarutkan La2O3 dan Na2SiO3 dengan mol ratio 1,555 menggunakan mineraliser NaOH (3-5 M) dan KOH (0,3-0,7 M). Hasil penelitian menunjukkan bahwa kinerja elektrolit sangat ditentukan oleh kristalinitas dan morfologi apatit lanthanum silikat yang dipengaruhi oleh jenis dan konsentrasi mineralizer. Ukuran apatit lantanum silikat terkecil diperoleh dari hasil sintesis dengan menggunakan mineraliser NaOH 3 M yaitu 1,7889 µm, dengan nilai konduktivitas tertinggi yaitu 1,99×10-6 S/cm pada suhu operasi 600 ºC. Berdasarkan hasil tersebut NaOH 3 M merupakan mineraliser yang paling baik untuk menghasilkan apatit lanthanum silikat La9.33Si6O26.Conductivity of Lanthanum Silicate Apatite Phase of La9.33Si6O26 Prepared by Hydrothermal Synthesis using NaOH and KOH as Mineralizer. Lanthanum silicates are used as electrolytes in solid oxide fuel cells (SOFC). Some oxide-based apatite has been synthesized by hydrothermal method to observe mineralizer effect on the process of crystallization. The effect of type and amount of mineralizers for preparing apatite –type lanthanum silicate of La9.33Si6O26 was investigatedon its crystallinity, particle size, as well as on the conductivity properties relationship were investigated. The structure, particle size and conductivity of La9.33Si6O26 was characterized using X-ray diffraction, particle size analyzer and impedance spectroscopy respectively. The results show that the electrolyte performance is strongly dependent on the crystallinity and the morphology textural of lanthanum silicate apatite affected by the type and amount of mineralizer. The lanthanum silicate apatiteprepared by La2O3 and Na2SiO3 (molar ratio of La2O3 and Na2SiO3 = 1.555), and NaOH (3; 4; 5 M) and KOH (0,3-0,7 M) as mineralizer. As a result, apatite-type lanthanum silicate was prepare using NaOH 3 M shows smallest particle (1.7889 μm) and highest conductivity (1.99 × 10-6 S / cm at 600 ºC). With respect to both particle size and conductivity, the NaOH 3 M can be selected as a suitable type and amount mineralizer for the preparation of excellent lanthanum silicate apatite La9.33Si6O26.

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Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽

10.3390/catal11030346 ◽

2021 ◽

Vol 11 (3) ◽

pp. 346

Author(s):

Sonam Goyal ◽

Maizatul Shima Shaharun ◽

Ganaga Suriya Jayabal ◽

Chong Fai Kait ◽

Bawadi Abdullah ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Catalyst Support ◽

Oxidation Potential ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Molar Ratios ◽

Optimum Parameters ◽

Reduction Of Co2 ◽

Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

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Fe3O4 Magnetic Preparation by Bauxite Ore Washing Fine Mud

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1010-1012.961 ◽

2014 ◽

Vol 1010-1012 ◽

pp. 961-965

Author(s):

Jian Qiang Xiao ◽

Guo Wei He ◽

Yan Jin Hu

Keyword(s):

Particle Size ◽

Aging Time ◽

Average Particle Size ◽

Xrd Analysis ◽

Test Methods ◽

Raw Material ◽

Molar Ratio ◽

Average Particle ◽

Experimental Conditions ◽

Particle Size Analyzer

Bauxite waste sludge as a raw material, the use of reverse chemical coprecipitation synthesize Fe3O4. Researching temperature, precipitation concentration, aging time and Fe2+/Fe3+ molar ratio effect on the particle size, morphology. Optimal experimental conditions: temperature 70 °C, the precipitant NaOH mass ratio of 10%, aging time 3h, Fe2+/Fe3+ molar ratio of 2:3. Test methods using a laser particle size analyzer, XRD analysis of the products were characterized, the product is Fe3O4, the average particle size of 0.11mm.

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Sol-gel synthesis and characterization of Ag nanoparticles in ZrO2 thin films

Journal of Materials Research ◽

10.1557/jmr.2009.0314 ◽

2009 ◽

Vol 24 (8) ◽

pp. 2541-2546 ◽

Cited By ~ 7

Author(s):

Eisuke Yokoyama ◽

Hironobu Sakata ◽

Moriaki Wakaki

Keyword(s):

Thin Films ◽

Sol Gel ◽

Composite Films ◽

Dip Coating ◽

Molar Ratio ◽

X Ray Diffraction ◽

Silver Surface ◽

Molar Ratios ◽

Sol Gel Synthesis

ZrO2 thin films containing silver nanoparticles were prepared using the sol-gel method with Ag to Zr molar ratios [Ag]/[Zr] = 0.11, 0.25, 0.43, 0.67, 1.00, 1.50, and 2.33. After dip coating on glass substrate, coated films were annealed at 200 and 300 °C in air. X-ray diffraction peaks corresponding to crystalline Ag were observed, but a specific peak corresponding to ZrO2 was not observed. At the molar ratio [Ag]/[Zr] = 0.25, the particle size of Ag distributed broadly centered at 17 nm for an annealing temperature of 200 °C and at 25 nm for 300 °C. The films annealed in air at 200 °C showed an absorption band centered at 450 nm because of the silver surface plasmon resonance, whereas films heated at 300 °C in air caused a red shift of the absorption to 500 nm. The absorption peak was analyzed using the effective dielectric function of Ag-ZrO2 composite films modeled with the Maxwell-Garnett expression.

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Valorization of Brick and Glass CDWs for the Development of Geopolymers Containing More Than 80% of Wastes

Minerals ◽

10.3390/min10080672 ◽

2020 ◽

Vol 10 (8) ◽

pp. 672

Author(s):

Dimitris Kioupis ◽

Aggeliki Skaropoulou ◽

Sotirios Tsivilis ◽

Glikeria Kakali

Keyword(s):

Electron Microscopy ◽

Compressive Strength ◽

Circular Economy ◽

X Ray Diffraction ◽

Glass Waste ◽

X Ray ◽

Optimum Synthesis ◽

Synthesis Parameters ◽

Construction And Demolition Wastes ◽

Scanning Electron

One of the areas of priority in a circular economy, regarding waste management, regards the valorization of construction and demolition wastes (CDW). This study suggests the synthesis of geopolymeric binders based almost entirely on construction and demolition wastes. Ceramic waste was used as the aluminosilicate precursor of the geopolymer synthesis, while glass waste was applied in the preparation of the activation solution. A fractional experimental design defined the optimum synthesis parameters, based on compressive strength values. The final products were characterized by means of X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The glass waste was appropriately processed in order to prepare the activation solution for the geopolymerization of brick waste. In this work, CDW-based geopolymers were produced with a compressive strength in the range 10–44 MPa. The developed products contained 80–90 wt.% CDWs, depending on the method of activator preparation.

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The Influence of Calcination Temperature on Quantitative Phase of Hematite from Iron Stone Tanah Laut

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1112.489 ◽

2015 ◽

Vol 1112 ◽

pp. 489-492

Author(s):

Ali Mufid ◽

M. Zainuri

Keyword(s):

Particle Size ◽

Calcination Temperature ◽

Thermo Gravimetric Analysis ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Particle Size Analyzer ◽

Co Precipitation

This research aims to form particles of hematite (α-Fe2O3) with a basis of mineral iron ore Fe3O4 from Tanah Laut. Magnetite Fe3O4 was synthesized using co-precipitation method. Further characterization using X-ray fluorescence (XRF) to obtain the percentage of the elements, obtained an iron content of 98.51%. Then characterized using thermo-gravimetric analysis and differential scanning calorimetry (TGA-DSC) to determine the calcination temperature, that at a temperature of 445 °C mass decreased by 0.369% due to increase in temperature. Further Characterization of X-ray diffraction (XRD) to determine the phases formed at the calcination temperature variation of 400 °C, 445 °C, 500 °C and 600 °C with a holding time of 5 hours to form a single phase α-Fe2O3 hematite. Testing with a particle size analyzer (PSA) to determine the particle size distribution, where test results indicate that the α-Fe2O3 phase of each having a particle size of 269.7 nm, 332.2 nm, 357.9 nm, 412.2 nm. The best quantity is shown at a temperature of 500 °C to form the hematite phase. This result is used as the calcination procedure to obtain a source of Fe ions in the manufacture of Lithium Ferro Phosphate.

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Effect of Process on the Dielectric Properties of BaTiO3-Based X9R Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.906.18 ◽

2014 ◽

Vol 906 ◽

pp. 18-24 ◽

Cited By ~ 1

Author(s):

Bao Lin Zhang ◽

Bin Bin Zhang ◽

Ning Ning Wang ◽

Jing Ming Fei

Keyword(s):

Particle Size ◽

Dielectric Properties ◽

Milling Time ◽

Sintering Temperature ◽

Sintering Process ◽

X Ray Diffraction ◽

Sintered Ceramic ◽

X Ray ◽

Particle Size Analyzer

The effect of milling time and sintering process on the dielectric properties of BaTiO3-based X9R ceramics was investigated. The characterization of the raw powders and the sintered ceramic was carried out by X-ray diffraction and scanning electron microscopy. The particle size distribution of the mixed powders was examined by Laser Particle Size Analyzer. The results shown that with the milling time extended, the Cruie Peak was depressed, or even disappeared. Moreover, with the rise of sintering temperature, the dielectric constant of the ceramics increased and the dielectric loss decreased gradually. Eventually, by milling for 11h and sintering at 1090°Cfor 2h, good dielectric properties were obtained, which were ε25°C≥ 2526, εr/εr25°C≤± 12% (–55~200°C), tanδ≤1.12% (25°C).

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Metakaolinite Phosphate Cementitious Matrix: Inorganic Polymer Obtained by Acidic Activation

Materials ◽

10.3390/ma12030442 ◽

2019 ◽

Vol 12 (3) ◽

pp. 442 ◽

Cited By ~ 5

Author(s):

Antigoni Katsiki ◽

Tobias Hertel ◽

Tine Tysmans ◽

Yiannis Pontikes ◽

Hubert Rahier

Keyword(s):

Compressive Strength ◽

Optimum Composition ◽

Molar Ratio ◽

High Porosity ◽

X Ray Diffraction ◽

Promising Candidate ◽

Cementitious Matrix ◽

Molar Ratios ◽

Optimal Behavior ◽

Amorphous Network

This work aims to study an aluminosilicate phosphate cementitious matrix. The cementitious matrix was studied on paste samples. The synthesis of metakaolinite phosphate cement (MKPC) was investigated using calorimetric techniques. A systematic study was performed by emphasizing a broad range of Al/P molar ratios, covering the different behavior of the material to the extremes, as well as the optimum composition. X-ray diffraction and scanning electron microscopy revealed that the final structure was mainly an amorphous network, albeit with some non-reacted phases. The compressive strength was studied on mortars using a cement/sand ratio of 1:3. MKPC specimens with Al/P ratios close to 1/1 showed optimal behavior. MKPCs with Al/P ratios above 1/1 were characterized by high porosity and low strength, whereas MKPCs with Al/P < 1 contained an excess of phosphates. The influence of the Al/P molar ratio on compressive strength was also studied, reaching a maximum of 68 MPa for the optimum composition. Based on the results, MKPC may be a promising candidate for construction purposes.

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Synthesis of Silver Nanoparticles Using Muntingia Calabura L. Leaf Extract as Bioreductor and Applied as Glucose Nanosensor

Oriental Journal Of Chemistry ◽

10.13005/ojc/340652 ◽

2018 ◽

Vol 34 (6) ◽

pp. 3088-3094 ◽

Cited By ~ 6

Author(s):

Abdul Wahid Wahab ◽

Abdul Karim ◽

Nursiah La Nafie ◽

Nurafni Nurafni ◽

I. Wayan Sutapa

Keyword(s):

Particle Size ◽

Silver Nanoparticles ◽

Reduction Method ◽

Measurement Range ◽

Structure Characterization ◽

X Ray Diffraction ◽

X Ray ◽

Particle Size Analyzer ◽

Muntingia Calabura

Silver nanoparticles have been synthesized by reduction method using extract of Muntingia calabura L. leaf a bioreductor. The process of silver nanoparticles formation was monitored by UV-Vis method. The results showed that the absorbance values increased according to the increase of reaction time. Maximum absorption of silver nanoparticle was obtained at a wavelength of 41-421 nm. The size of silver nanoparticles was determined using a PSA (Particle Size Analyzer) with a particle size distribution of 97.04 nm. The functional groups compound that contribute in the synthesis was analyzed using Fourier Transform Infrared Spectroscopy (FTIR). Morphology of the silver nanoparticles was observed by an Scanning Electron Microscope instrument and the structure characterization of the compounds were analyzed using X-Ray Diffraction. The glucose nanosensor based on silver nanoparticles have the measurement range of 1 mM - 4 mM with the regretion (R2) is 0,9516, the detection limit of sensor is 3,2595 mM, the sensitivity of sensor is 2,0794 A. mM-1. mM-2.

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