Synthesis and Characterization of the ZSM-5/MCM-41 Composite Molecular Sieves

2011 ◽  
Vol 480-481 ◽  
pp. 165-169 ◽  
Author(s):  
Li Qin Wang ◽  
Ning Yu ◽  
Yang Han ◽  
Xiang Ni Yang ◽  
Xiu Li Zhao
Keyword(s):  
Molecular Sieves ◽  
Cetyltrimethylammonium Bromide ◽  
Decomposition Temperature ◽  
High Thermal Stability ◽  
Hydrothermal Crystallization ◽  
X Ray ◽  
Ft Ir ◽  
Prepared Composite ◽  
Mcm 41

The ZSM-5/MCM-41 composite molecular sieves were synthesized in the method of hydrothermal crystallization in the presence of cetyltrimethylammonium bromide (CTMABr) as template agent. The prepared composite molecular sieves were characterized by the means of X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and the thermogravimetric and differential thermal analysis (TG-DTA). The experimental results showed that as-prepared ZSM-5/MCM-41 composite molecular sieves kept both crystal structure and compositions of ZSM-5 zeolites and MCM-41 molecular sieves. The decomposition temperature of the template agent was 293°C, and the decomposition temperature of the molecular sieve framework was higher than 800 °C. We supposed that the obtained ZSM-5/MCM-41 composite molecular sieves had high thermal stability, framework rigidity and structural stability, and could combine the properties of ZSM-5 zeolites and MCM-41 molecular sieves successfully.

Synthesis and Characterization of MCM-41 Molecular Sieves Nanoparticals

2013 ◽  
Vol 662 ◽  
pp. 214-217 ◽  
Author(s):  
Li Qin Wang ◽  
Yang Han ◽  
Xiu Jun Fu ◽  
Hai Tao Wu ◽  
E Chang ◽  
...  
Keyword(s):  
Molecular Sieves ◽  
Room Temperature ◽  
Mesoporous Structure ◽  
Decomposition Temperature ◽  
Surface Areas ◽  
Type Iv ◽  
Typical Type ◽  
Ft Ir ◽  
Adsorption Desorption ◽  
Mcm 41

Nanoparticals of MCM-41 molecular sieves were synthesized at near room temperature with cetyltrimethylammonium bromide (CTAB) as template agent. The prepared samples were characterized by the means of scanning electron microscopy (SEM), X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), N2 adsorption tests, thermogravimetric and differential thermal analysis (TG-DTA). The results suggested that morphology of MCM-41 molecular sieves samples with high crystallinity was almost uniform spherical, and the particles size was almost less than 100 nm. The adsorption-desorption isotherms were corresponded to typical type IV isotherms with the hysteresis loop of type H2, which showed the samples had mesoporous structure. The pore size distribution of samples were 1.69 nm and 3.58 nm, and the specific surface areas was up to 752.23 m2/g. The decomposition temperature of template agent CTAB was around 327 °C, while the framework for MCM-41molecular sieves was stable. So MCM-41 molecular sieve samples synthesized at near room temperature had excellent physical properties.

Synthesis and Characterization of the Y/MCM-41 Composite Molecular Sieves

2011 ◽  
Vol 480-481 ◽  
pp. 159-164 ◽  
Author(s):  
Li Qin Wang ◽  
Xiang Ni Yang ◽  
Yang Han ◽  
Ning Yu ◽  
Xiu Li Zhao
Keyword(s):  
Pore Size ◽  
Molecular Sieves ◽  
Average Pore Size ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Decomposition Temperature ◽  
Average Pore ◽  
Y Zeolites ◽  
Ft Ir ◽  
Mcm 41

The Y/MCM-41 composite molecular sieves were synthesized in the method of hydrothermal crystallization with cetyltrimethylammonium bromide (CTMABr) as the template agent. The as-prepared composite molecular sieves were characterized by the means of X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), the thermogravimetric and differential thermal analysis (TG-DTA) and the nitrogen adsorption test. The experimental results were shown as follows: the Y/MCM-41 composite molecular sieves kept properties of Y-zeolites and MCM-41 molecular sieves. In the XRD and FT-IR spectra, it can be found both characteristic peaks of Y-zeolites and MCM-41 molecular sieves. The pore size distribution plot indicated that the Y/MCM-41composite molecular sieves had micro-mesoporous structure, and the average pore size were about 1.5 nm and 15 nm. The decomposition temperature of the template agent was at 320 °C, and the calcined temperature of Y-zeolites was at about 560 °C. There showed an endothermic process constantly in the DTA curve, and there was little mass loss in the TG curve, indicating the obtained Y/MCM-41 composite molecular sieves had higher thermal stability.

Synthesis and Characterization of n-HA/PVA/Gel Composite

2007 ◽  
Vol 330-332 ◽  
pp. 471-474 ◽  
Author(s):  
Ming Bo Wang ◽  
Yu Bao Li ◽  
Feng Lan Xu ◽  
Gang Zhou ◽  
Lin Cheng
Keyword(s):  
Synthesis And Characterization ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Prepared Composite ◽  
Pva Gel ◽  
Good Homogeneity

A unique composite consisted of nano-hydroxyapatite (n-HA), poly (vinyl alcohol) (PVA) and gelatin (Gel), was prepared and characterized by Fourier transform infrared absorption spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and burning test. The homogenicity of the composite was evaluated, and the presence of interior chemical bond was confirmed and discussed. Mechanical strength and water absorption of the prepared composite were investigated, respectively. The results show that n-HA/PVA/Gel composite has good homogeneity, similar mechanical properties to natural cartilage and excellent in vivo biocompatibility.

Thermal Behaviour of Candesartan Active substance and in pharmaceutical compounds

2017 ◽  
Vol 68 (8) ◽  
pp. 1895-1902
Author(s):  
Ioana Cristina Tita ◽  
Eleonora Marian ◽  
Bogdan Tita ◽  
Claudia Crina Toma ◽  
Laura Vicas
Keyword(s):  
Thermal Behaviour ◽  
Active Substance ◽  
Pharmaceutical Research ◽  
Pharmaceutical Product ◽  
Nitrogen Atmosphere ◽  
Pure Substance ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir

Thermal analysis is one of the most frequently used instrumental techniques in the pharmaceutical research, for the thermal characterization of different materials from solids to semi-solids, which are of pharmaceutical relevance. In this paper, simultaneous thermogravimetry/derivative thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) were used for characterization of the thermal behaviour of candesartan cilexetil � active substance (C-AS) under dynamic nitrogen atmosphere and nonisothermal conditions, in comparison with pharmaceutical product containing the corresponding active substance. It was observed that the commercial samples showed a different thermal profile than the standard sample, caused by the presence of excipients in the pharmaceutical product and to possible interaction of these with the active substance. The Fourier transformed infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRPD) were used as complementary techniques adequately implement and assist in interpretation of the thermal results. The main conclusion of this comparative study was that the TG/DTG and DSC curves, together with the FT-IR spectra, respectively X-ray difractograms constitute believe data for the discrimination between the pure substance and pharmaceutical forms.

One Step Synthesis and Characterization of Zirconia-Graphene Composites

2012 ◽  
Vol 600 ◽  
pp. 174-177 ◽  
Author(s):  
Jian Fei Xia ◽  
Zong Hua Wang ◽  
Yan Zhi Xia ◽  
Fei Fei Zhang ◽  
Fu Qiang Zhu ◽  
...  
Keyword(s):  
Synthesis And Characterization ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Graphene Composite ◽  
Transmission Electron ◽  
One Step ◽  
Ft Ir ◽  
Xrd Techniques

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.

Synthesis and Characterization of a Novel Linear Benzoxazine-Containing Polytriazole via Metal-Free Click Reaction and its Self-Crosslinking Behavior

2012 ◽  
Vol 557-559 ◽  
pp. 973-978
Author(s):  
Zhong Yi Xu ◽  
Lei Du ◽  
Li Qiang Wan ◽  
Fa Rong Huang
Keyword(s):  
Click Reaction ◽  
Decomposition Temperature ◽  
Linear Polymer ◽  
The Novel ◽  
Metal Free ◽  
Crosslinked Polymer ◽  
Degradation Behaviors ◽  
Ft Ir ◽  
Increasing Temperature

A novel linear benzoxazine-containing polytriazole was successfully synthesized via metal-free click reaction. Benefited from the advantages of click reaction, the synthesis procedure was easily and efficiently. The linear polymer could be transformed into crosslinked structure after ring-opening polymerization of oxazine induced by the increasing temperature. The FT-IR characterization verified the structure transformation between linear and crosslinked polymer. Moreover, the thermal properties and thermal degradation behaviors of linear polymer and the corresponding crosslinked polymer were studied by DSC and TGA. The novel polytriazole was proved to be a kind of thermal stable polymers with high thermal decomposition temperature (Td5over 300°C).

scholarly journals Synthesis and Characterization of Nanoporous Monetite Which Can Be Applicable for Drug Carrier

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Esmael Salimi ◽  
Jafar Javadpour
Keyword(s):  
Surface Area ◽  
Cetyltrimethylammonium Bromide ◽  
Drug Carrier ◽  
Synthesis And Characterization ◽  
X Ray ◽  
Plate Shape ◽  
Desorption Isotherms ◽  
Adsorption Desorption

Wormhole-like mesostructured monetite was successfully synthesized using cetyltrimethylammonium bromide (C19H42BrN, CTAB), as a porosity agent. X-ray techniques and FTIR reveal that the crystalline grains consist of highly crystalline pure monetite phase. Monetite rods with diameter around 20–40 nm and length in the range of 50–200 nm were confirmed by FESEM and TEM. Based on N2adsorption-desorption isotherms investigation, surface area increased up to 31.5 m2/g due to the removal of surfactant after calcinations at 400°C. The results indicate that CTAB can not only affect monetite crystallization but also change particles morphology from plate shape to rod-like.

Microwave-assisted solvent-free synthesis and spectral and structural characterization of cyclotriphosphazene hexakis(o-tolylamide)

2018 ◽  
Vol 73 (12) ◽  
pp. 999-1003 ◽  
Author(s):  
Mohammad Hakimi ◽  
Homeyra Rezaei ◽  
Keyvan Moeini ◽  
Heidar Raissi ◽  
Vaclav Eigner ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Microwave Irradiation ◽  
Stacking Interactions ◽  
X Ray Diffraction ◽  
Aromatic Rings ◽  
X Ray ◽  
Microwave Assisted ◽  
Ft Ir ◽  
Solvent Free Synthesis

AbstractA new cyclotriphosphazene, 2,2,4,4,6,6-hexakis (o-tolylamono)-1,3,5,2λ5,4λ5,6λ5-triazatriphosphinine (MPAP), was prepared using microwave irradiation and identified by elemental analysis, FT-IR, Raman, 31P NMR spectroscopy, and single-crystal X-ray diffraction. In the crystal, in addition to hydrogen bonds, the network is further stabilized by inter- and intramolecular π–π stacking interactions between aromatic rings.

Structure and Properties of Modifier for Heat Transfer Printing on Cotton Fabric

2011 ◽  
Vol 331 ◽  
pp. 426-429
Author(s):  
Yi Mu ◽  
Lan Wang ◽  
Ming Hua Wu ◽  
Jun Xiong Lin
Keyword(s):  
Heat Transfer ◽  
Spherical Shape ◽  
Decomposition Temperature ◽  
Polymerization Process ◽  
Structure And Properties ◽  
Transfer Printing ◽  
Transmission Electron ◽  
Ft Ir ◽  
Regular Spherical Shape

Modifier for heat transfer printing on cotton fabrics was prepared by semi-continuous emulsion polymerization process with butyl acrylate (BA), styrene (St), acrylonitrile (AN) and cross-linking monomer. FT-IR characterization of modifier groups showed that individual monomer well carried out polymerization. Transmission electron microscopy (TEM) photos demonstrated that latex particles had regular spherical shape and uniform distribution. TGA curves indicated that thermal decomposition temperature of modifier was 439 oC. As for the transfer printing products had good colour fastness, high transfer rate and no formaldehyde.

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