scholarly journals SYNTHESIS OF In-CONTAINING HIGH-SILICA ZEOLITE OF ZSM-5 TYPE

2017 ◽  
Vol 60 (8) ◽  
pp. 84
Author(s):  
Khasay R. Samedov ◽  
Ulviya A. Mamedova ◽  
Kerim G. Ragimov ◽  
Zarema A. Jabbarova
Keyword(s):  
Degree Of Crystallinity ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Solid Product ◽  
X Ray ◽  
Type Zeolite ◽  
High Silica ◽  
Tetrabutylammonium Iodide ◽  
High Degree ◽  
Ratio Of Components

High silicate zeolite ZSM-5 on the basis of SiO2–In2O3–NaOH with an organic structure forming agent tetrabutylammonium iodide (TBAI) was synthesized in the temperature range of T = 150–220°C, pH = 9-12, τ = 48-240 h. As initial components, silica gel MSKO containing 86% SiO2, tetrabutylammonium iodide (TBAI), chemically pure NaOH and metallic indium (In) were used which mixed by hydrothermal synthesis. At the end of the synthesis, the solid product was separated from the mother liquor, washed on the filter with distilled water from an excess of alkali and dried at 120 °C, calcined at 550 °C (16 h). The products of hydrothermal crystallization were determined by X-ray (RFA – on the device D2-Phaser "Bruker"), differential thermal (DTA- STA-449 F3 Jupiter NETZSCH), by X-ray diffraction (XRD of brand SRM-18) and infrared spectroscopy (IR on FTIR spectroscopy, Nicolefisio VSA) analysis methods. During the synthesis, it was experimentally established that at T = 200 °C; τ = 240 h; pH≈9-10 molar ratio of components 5.78SiO2∙0.058In2O3∙0.625Na2O∙0.11H2O∙0.95 ((C4H9) 4NJ) – MFI-type zeolite is crystallized. When comparing XRF data with literature data, they were referred to a type zeolite of ZSM-5 differing in high degree of crystallinity. The following chemical composition of the synthesized zeolite (wt.%) was established by the X-ray diffraction (SRM-18) method: SiO2 – 94.01; In2O3 – 4.92; Na2O – 1.06 corresponding to the formula 0.96Na2O:In2O3:88SiO2:10H2O.Forcitation:Samedov Kh.R., Mamedova U.A., Ragimov K.G., Jabbarova Z.A. Synthesis of In-containing high-silica zeolite of ZSM-5 type.Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 8. P. 84-87.

Heteroepitaxial Growth of Ba0.5Sr0.5TiO3/SrRuO3 on YSZ/Si by Off-Axis Sputtering

1994 ◽  
Vol 361 ◽  
Author(s):  
S.Y. Hou ◽  
J. Kwo ◽  
R.K. Watts ◽  
J.-Y. Cheng ◽  
R.J. Cava ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Degree Of Crystallinity ◽  
Heteroepitaxial Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Dielectric Constant And Loss ◽  
Bst Films ◽  
High Degree ◽  
Room Temperature Dielectric Constant

ABSTRACTWe demonstrate an epitaxial heterostructure of Ba0.5Sr0.5 TiO3/SrRuO3/YSZ on Si for potential charge storage applications. The dielectric Ba0.5Sr0.5TiO3 (BST) and conductive oxide SrRuO3 are both grown (110) oriented on YSZ (100) buffered Si by 90° off-axis sputtering. These films showed a high degree of crystallinity with minimal interdiffusion at the interfaces as examined by X-ray diffraction, Rutherford backscattering spectroscopy, and cross-section transmission electron microscopy. The in-plane epitaxial alignment of the films is BST/SRO 〈111〉 // YSZ 〈110〉 with a four-fold degeneracy. The dielectric constant and loss tangent of the epi-BST films are 360 and 0.01 at 10 kHz. The leakage current density is < 4×10∼−7 A/cm2 at 1 V. The room temperature dielectric constant (ε) of the BST films shows a roll-off in the 1–10 MHz range. This is attributed to the existence of a series resistance in the measurement circuit, which likely arises from the SrRuO3 electrode.

scholarly journals Synthesis and Characterization of Zeolite X from Boiler Ash and Aluminum Foil Waste

2021 ◽  
Vol 4 (1) ◽  
pp. 15
Author(s):  
Intan Ayu Safitri ◽  
Iis Siti Jahro
Keyword(s):  
Aluminum Foil ◽  
Degree Of Crystallinity ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Zeolite X ◽  
X Ray ◽  
X Zeolite ◽  
Ft Ir ◽  
Boiler Ash

This study aims to determine the effect of the Si/Al molar ratio and the number of Na2EDTA additions on the purity and crystallinity levels of the synthesized zeolite X. zeolite X was synthesized by hydrothermal method at 70°C and 120°C for 3 and 6 hours, respectively. In the synthesis of zeolite X used boiler ash and aluminum foil waste. The results of characterization using Fourier Transform Infra Red (FT-IR) and X-Ray Diffraction (XRD) showed that the level of purity and crystallinity of the synthesized zeolite X was influenced by the variation of Si/Al molar rasio and amount of Na2EDTA addition. The zeolite with the best quality was obtained from the synthesis with a Si/Al molar ratio of 1.6 and the amount of Na2EDTA added as much as 3.0 g. The synthesized zeolite X has a purity level of 75% and a degree of crystallinity with a total intensity of 845.

scholarly journals CRYSTAL STRUCTURE AND RIETVELD REFINEMENT OF ZEOLITE A SYNTHESIZED FROM FINE-GRAINED PERLITE WASTE MATERIALS

2004 ◽  
Vol 36 (1) ◽  
pp. 121 ◽  
Author(s):  
V. Psycharis ◽  
V. Perdikatsis ◽  
G. Christidis
Keyword(s):  
Crystal Structure ◽  
Reaction Time ◽  
Rietveld Method ◽  
Amorphous Material ◽  
Degree Of Crystallinity ◽  
Molar Ratio ◽  
Zeolite A ◽  
X Ray ◽  
Fine Grained ◽  
High Degree

Synthetic zeolites have been produced from a variety of natural silica-rich rocks including volcanic glasses, such as perlite and pumice. The Zeolite studied in this work has been synthesized from perlite and expanded perlite fines. Detailed powder X-ray diffraction studies determined it as Zeolite A. In early studies the structure of Zeolite-Α was described with a cubic cell with a=12.3 A and space group Pm-3m. However the observation of the (531) reflection indicates that a F lattice with a larger cell of 24.60 A gives a more accurate description. Two end products were studied on the basis of the degree of crystallization of the parent gels to zeolite A . One end product was characterized by total conversion of the incipient gel to zeolite A with high degree of crystallinity, whereas in the second a substantial amount of the original gel did not crystallize out and zeolite A coexisted with amorphous material. The former resulted from gels with S1O2/AI2O3 molar ratio 2:1 and 5 hours reaction time and the latter from gels with SÌO2/AI2O3 molar ratio of 2.5:1 and 3 hours reaction time. The X-ray powder diffraction data recorded from the former sample were used for the analysis of the crystal structure of zeolite A and the final model was refined by the Rietveld method.

Novel Strontium Doped Zinc Calcium Phosphate Conversion Coating on AZ31 Magnesium Alloy for Biomedical Applications

2017 ◽  
Vol 34 ◽  
pp. 57-67 ◽  
Author(s):  
P. Amaravathy ◽  
T.S. Sampath Kumar
Keyword(s):  
Magnesium Alloy ◽  
Calcium Phosphate ◽  
Chemical Conversion ◽  
Conversion Coating ◽  
Az31 Magnesium Alloy ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Simple Chemical ◽  
High Degree

A simple chemical conversion coating was adopted to deposit zinc calcium phosphate (ZCP) coating and strontium doped ZCP (SZCP) coating on AZ31 magnesium alloy to induce biocompatibility and reduce the degradation rate. The surface morphology, chemical composition and functional groups of the coating were characterized by Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (SEM-EDS), X-Ray Diffraction (XRD) studies and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy respectively. SZCP coating formed at 20 min deposition time produced crack free surface with a high degree of crystallinity with barrier property, which ultimately retards the dissolution of magnesium in Simulated Body Fluid (SBF). The corrosion resistance of AZ31 magnesium alloy was improved by SZCP coating as evident from hydrogen evolution test (HET). Cytotoxicity evaluation with L969 cells showed that Sr doped ZCP coatings showed less toxicity on resorbable magnesium alloys.

scholarly journals Efficient Hydrothermal Synthesis of SSZ-13 with Variable Grain Size

Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1829 ◽  
Author(s):  
Yibao Wang ◽  
Chen Wang ◽  
Jun Wang ◽  
Jianqiang Wang ◽  
Lei Wang ◽  
...  
Keyword(s):  
Hydrothermal Synthesis ◽  
Size Distribution ◽  
Degree Of Crystallinity ◽  
Similar Degree ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grain Sizes ◽  
Seed Method ◽  
Industrial Needs ◽  
High Degree

To meet the industrial needs for SSZ-13, variable sizes of SSZ-13 with different Si/Al ratios were firstly obtained by conventional hydrothermal synthesis using the seed method. Using a set of characterizations, like X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy (SEM), the physicochemical structure and size distribution could be traced. After the specific Si/Al ratio of SSZ-13 zeolites was optimized, synthesized by changing the amounts of structure-directing agents (SDAs) and NaOH, the obtained SSZ-13 showed a high degree of crystallinity. With the limitation of the pH values, the variation of the alkalinity and water content was not helpful to generate different grain sizes of SSZ-13 materials. With the help of ground seed, the various grain sizes of SSZ-13s from 0.4 to 4 μm had a similar degree of crystallinity and size distribution. Moreover, due to the identical intensity of the Al peak in the NMR results, the different grain sizes of SSZ-13s had the same acidity. Our study revealed that using the seed method was an easy and efficient way to synthesize SSZ-13s with different sizes.

Isolation of Microfibrillated Cellulose (MFC) from Local Hardwood Waste, Resak (Vatica spp.)

2016 ◽  
Vol 846 ◽  
pp. 679-682 ◽  
Author(s):  
Nurul Aimi Mohd Zainul Abidin ◽  
Fauziah Abdul Aziz ◽  
Shahidan Radiman ◽  
Ariffin Ismail ◽  
Wan Md Zin Wan Yunus ◽  
...  
Keyword(s):  
High Pressure ◽  
Acid Hydrolysis ◽  
Mineral Acid ◽  
Microfibrillated Cellulose ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Treatments ◽  
High Degree ◽  
Scanning Electron

Micrifibrillated cellulose (MFC) is generally can be prepared either by acid hydrolysis, chemical treatments, or by a high pressure refiner. In this study, the MFC of Resak’s hardwood waste with high degree of crystallinity has been obtained by an acid hydrolysis using mineral acid H2SO4. The microstructures of the MFC were characterized via X-ray diffraction (XRD) and Field emission scanning electron microscope (FESEM).

On the Properties of an Ion Conductive System Incorporated in Hybrid Films

2000 ◽  
Vol 628 ◽  
Author(s):  
G. González ◽  
P. J. Retuert ◽  
S. Fuentes
Keyword(s):  
Electrochemical Impedance ◽  
Ternary Phase Diagram ◽  
Lithium Perchlorate ◽  
Molar Ratio ◽  
Ionic Conductors ◽  
X Ray Diffraction ◽  
Poly Ethylene Oxide ◽  
Ion Conducting ◽  
Poly Ethylene ◽  
High Degree

ABSTRACTBlending the biopolymer chitosan (CHI) with poly (aminopropilsiloxane) oligomers (pAPS), and poly (ethylene oxide) (PEO) in the presence of lithium perchlorate lead to ion conducting products whose conductivity depends on the composition of the mixture. A ternary phase diagram for mixtures containing 0.2 M LiClO4 shows a zone in which the physical properties of the products - transparent, flexible, mechanically robust films - indicate a high degree of molecular compatibilization of the components. Comparison of these films with binary CHI-pAPS nanocomposites as well as the microscopic aspect, thermal behavior, and X-ray diffraction pattern of the product with the composition PEO/CHI/pAPS/LiClO4 1:0.5:0.6:0.2 molar ratio indicates that these films may be described as a layered nanocomposite. In this composite, lithium species coordinated by PEO and pAPS should be inserted into chitosan layers. Electrochemical impedance spectroscopy measurements indicate the films are pure ionic conductors with a maximal bulk conductivity of 1.7*10-5 Scm-1 at 40 °C and a sample-electrode interface capacitance of about 1.2*10-9 F.

Effect of Hydrated Metal Salts on the Coordination Product of Cobalt(II) halide and PNP Type Ligand, 2,6-bis(di-tertbutylphosphinomethyl) pyridine

2018 ◽  
Author(s):  
Tasneem Siddiquee ◽  
Abdul Goni
Keyword(s):  
Metal Salts ◽  
Molar Ratio ◽  
Pincer Complexes ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Pincer Ligand ◽  
Tetrahedral Geometry ◽  
X Ray ◽  
Distorted Tetrahedral Geometry ◽  
Cobalt Center

Chemical treatment of CoX<sub>2</sub><b><sup>. </sup></b>6H<sub>2</sub>O (X = Cl, Br, I) with the potentially tridentate PNP pincer ligand 2,6-bis(di-<i>tert</i>-butylphosphinomethyl)pyridine in 1:1 molar ratio results in cobalt(II) halide-PNP pincer complexes. The effect of the hydrated metal source on molecular structure and geometry of the complexes was studied by single crystal X-ray diffraction analysis. The complexes are neutral and the cobalt center adopts a penta-coordinate system with potential atropisomerization. Within the unit cell there are two distinct molecules per asymmetric unit. One of the two phosphorus atoms in the PNP ligand was observed to be partially oxidized to phosphinoxide. Disorder in the structure reflects a mixture of square pyramidal and distorted tetrahedral geometry.

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

Catalysts ◽  
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.

Low-temperature route to nanoscale P3N5 hollow spheres

2003 ◽  
Vol 18 (10) ◽  
pp. 2359-2363 ◽  
Author(s):  
Hongzhou Gu ◽  
Yunle Gu ◽  
Zhefeng Li ◽  
Yongcheng Ying ◽  
Yitai Qian
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hollow Spheres ◽  
Molar Ratio ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Influence Of Temperature On ◽  
Wide Gap ◽  
20 Nm ◽  
High Degree

Nanoscale hollow spheres of amorphous phosphorus nitride (P3N5) were synthesized by reacting PCl3 with NaN3 at 150–250 °C. Transmission electron microscope images show that the hollow spheres have a diameter of 150–350 nm, and the thickness of the shell is 20 nm. A very small amount of curly films were also found in the sample prepared at 150 °C. The infrared spectrum indicates a high degree of purity. X-ray photoelectron spectroscopy indicates the presence of P and N, with a molar ratio of 1:1.62 for P:N. Ultraviolet-visible absorption spectroscopy shows an absorption band at 265–315 nm. Under photoluminescent excitation at 230 nm, the P3N5 emits ultraviolet light at 305 nm. With a band gap of 4.28 eV, the products may be a wide gap semiconductor. A possible mechanism and the influence of temperature on the formation of the hollow spheres are also discussed.

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