Preparation Crystalline Mesoporous Titania at Mild Conditions with Inorganic Titanium Precursors

2010 ◽  
Vol 113-116 ◽  
pp. 2053-2056
Author(s):  
Yan Wang ◽  
Rui Qing Liu ◽  
Ai Hua Wen ◽  
Xuan Dong Li
Keyword(s):  
Soxhlet Extraction ◽  
Temperature Treatment ◽  
Mesoporous Tio2 ◽  
High Temperature Treatment ◽  
Mesoporous Titania ◽  
N2 Adsorption ◽  
Mild Conditions ◽  
Ft Ir ◽  
Adsorption Desorption ◽  
Additive Reaction

In order to avoid the damage on mesostructure by the high temperature treatment, inorganic titanium species were used as the precursors for the preparation of mesoporous TiO2 of crystalline framework at mild conditions. The influences of the precursor, additive, reaction pH and temperature on phase and textural structures of the products were investigated. The samples were characterized by XRD, N2 adsorption/desorption, FT-IR and SEM. The results show that anatase mesoporous TiO2 with large surface area could be obtained without calcination with Ti(SO4)2 as precursor or TiCl4 when SO42- was added. And the template could be completely removed by Soxhlet extraction.

Effect of L-Arginine on the Carbon Microsphere Forming under Hydrothermal Carbonization

2019 ◽  
Vol 41 (1) ◽  
pp. 72-72
Author(s):  
Jilei Liang Jilei Liang ◽  
Mengmeng Wu Mengmeng Wu ◽  
Hongmei Cai Hongmei Cai ◽  
Hao Wang Hao Wang ◽  
Hua Huang Hua Huang ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Adsorption Capacity ◽  
Surface Property ◽  
Condensation Reaction ◽  
Hydrothermal Carbonization ◽  
Carbon Microspheres ◽  
N2 Adsorption ◽  
Sem Images ◽  
Ft Ir ◽  
Adsorption Desorption

Carbon microspheres (CMs) with a diameter of 5-10 μm have been synthesized by hydrothermal carbonization of starch and L-arginine. The surface property and structure of CMs were examined by FT-IR spectra, N2 adsorption-desorption isotherms and SEM images. These characterizations indicated that the L-arginine does not connect into the CMs but it promotes the starch hydrolysis and polymerization-condensation reaction of intermediate, which accelerates the formation of CMs and improves the yield in shorter time. The surface property of CMs determines adsorption capacity for acetic acid. By contrast, the porosity resulted from the carbonization at 500 and#176;C dominates the adsorption capacity for acetic acid.

Preparation and Activity of Ionic Liquid Catalysts Grafted on Hydrophobic Silica Gel

2012 ◽  
Vol 476-478 ◽  
pp. 2621-2624
Author(s):  
Xue Lan Zhang ◽  
Deng Feng Wang
Keyword(s):  
Carbon Dioxide ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Silica Gel ◽  
Propylene Oxide ◽  
Heterogeneous Catalysts ◽  
N2 Adsorption ◽  
Mild Conditions ◽  
Hydrophobic Silica ◽  
Adsorption Desorption

An ionic liquid 1- (triethoxysilyl) propyl-3-methylimidazolium hydroxide ([Smim]OH) was grafted on three kinds of mesoporous hydrophobic silica gel by means of post-grafting under mild conditions. The catalysts were [Smim]OH/SiO2-MTES (methyltriethoxysilane), [Smim]OH/SiO2-TMCS (trimethylchlorosilane), [Smim]OH/SiO2-CPTEO (triethoxysilyl propyl chloride). Such grafted ionic liquids (GILs), which were characterized by means of FTIR and N2 adsorption-desorption could be used as effective heterogeneous catalysts toward propylene carbonate synthesis through cycloaddition of carbon dioxide with propylene oxide under solventless and mild conditions.

scholarly journals Synthesis of Small-Sized SAPO-34 Crystals with Varying Template Combinations for the Conversion of Methanol to Olefins

Catalysts ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 570 ◽  
Author(s):  
Yanjun Zhang ◽  
Zhibo Ren ◽  
Yinuo Wang ◽  
Yinjie Deng ◽  
Jianwei Li
Keyword(s):  
Molecular Sieves ◽  
Crystal Size ◽  
Ammonium Hydroxide ◽  
Methanol Conversion ◽  
29Si Mas Nmr ◽  
Hydrothermal Conditions ◽  
N2 Adsorption ◽  
Ft Ir ◽  
Ir Analysis ◽  
Adsorption Desorption

SAPO-34 molecular sieves were synthesized under hydrothermal conditions using different combinations of tetraethyl ammonium hydroxide (TEAOH)/morpholine (Mor)/triethylamine (TEA) as templates, with different silicon:aluminum ratios. The physicochemical properties of the synthesized SAPO-34 were characterized using XRD, SEM, N2 adsorption–desorption, XRF, TG, NH3-TPD, FT-IR, and 29Si MAS NMR analyses. According to the SEM and the N2 adsorption–desorption of the catalysts produced by the ternary template exhibited a larger surface area and a smaller crystal size than those produced by the single or binary templates. The FT-IR analysis indicated the increased acidity of the catalyst prepared by the ternary template. A high activity and selectivity to olefins (C2= + C3=) and an optimal silicon to aluminum ratio of 0.4 were obtained from the catalyst synthesized with the ternary template. At the reaction temperature of 450 °C, the methanol conversion approached 100% and the ethylene–propylene selectivity and the lifetime of the catalyst reached maximums of 89.15% and 690 min, respectively.

scholarly journals Novel Organically Modified Core-Shell Clay for Epoxy Composites—“SOBM Filler 1”

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Nnamdi Chibuike Iheaturu ◽  
Innocent Chimezie Madufor
Keyword(s):  
Weight Percent ◽  
Temperature Treatment ◽  
Epoxy Composites ◽  
High Temperature Treatment ◽  
Core Shell ◽  
Drilling Mud ◽  
Modified Clay ◽  
Hydrophilic Nature ◽  
Organically Modified ◽  
Ft Ir

Preparation of a novel organically modified clay from spent oil base drilling mud (SOBM) that could serve as core-shell clay filler for polymers is herein reported. Due to the hydrophilic nature of clay, its compatibility with polymer matrix was made possible through modification of the surface of the core clay sample with 3-aminopropyltriethoxysilane (3-APTES) compound prior to its use. Fourier transform infrared (FT-IR) spectroscopy was used to characterize clay surface modification. Electron dispersive X-ray diffraction (EDX) and scanning electron microscopy (SEM) were used to expose filler chemical composition and morphology, while electrophoresis measurement was used to examine level of filler dispersion. Results show an agglomerated core clay powder after high temperature treatment, while EDX analysis shows that the organically modified clay is composed of chemical inhomogeneities, wherein elemental compositions in weight percent vary from one point to the other in a probe of two points. Micrographs of the 3-APTES coupled SOBM core-shell clay filler clearly show cloudy appearance, while FT-IR indicates 25% and 5% increases in fundamental vibrations band at 1014 cm−1 and 1435 cm−1, respectively. Furthermore, 3-APTES coupled core-shell clay was used to prepare epoxy composites and tested for mechanical properties.

scholarly journals Catalytic Performance of Phosphorus Incorporated HZSM-5 in Coupling Transformation of Methanol with 1-butene to Propylene

2021 ◽  
Vol 72 (3) ◽  
pp. 33-44
Author(s):  
Haifeng Tian ◽  
Yongyong Nan ◽  
Jinlong Lv ◽  
Fei Zha ◽  
Xiaohua Tang ◽  
...  
Keyword(s):  
Fixed Bed ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
N2 Adsorption ◽  
Facile Hydrothermal Method ◽  
Phosphorus Species ◽  
Coupling Transformation ◽  
Ft Ir ◽  
Adsorption Desorption

Directly incorporated phosphorus species into the framework of HZSM-5 zeolite (H[P, Al]-ZSM-5) was successfully synthesized by the facile hydrothermal method. It was characterized by employing XRD, ICP-OES, SEM, FT-IR, N2 adsorption-desorption, NH3-TPD, XPS and TG-DTA, respectively. The effects of the phosphorus species content, temperature, WHSV, and the molar ratio of methanol/1-butene in coupling transformation of methanol with 1-butene to propylene catalyzed by H[P, Al]-ZSM-5 in a fixed bed reactor were studied systematically. Tests have suggested the acid content and specific surface area of H[P, Al]-ZSM-5 are reduced. Under the condition of reaction temperature at 550�Z, molar ratio of methanol/1-butene to 1.0, reaction pressure at 0.1 MPa and WHSV= 3.53 h-1, the P-modified HZSM-5 zeolite (with the P2O5 molar composition of 0.4 )the selectivity and yield of propylene are 35.6% and 32.5%, respectively.

scholarly journals Synthesis of Zeolitic - Imidazolate Framework - 67 in Ethanol by Using Ultrasonication 

2021 ◽  
Vol 31 (1) ◽  
pp. 11-15
Keyword(s):  
Methylene Blue ◽  
Surface Area ◽  
Bet Surface Area ◽  
Thermal Method ◽  
N2 Adsorption ◽  
Zeolitic Imidazolate Framework ◽  
Synthesis Time ◽  
Nano Material ◽  
Ft Ir ◽  
Adsorption Desorption

The ZIF-67 nanocrystal was successfully synthesized in ethanol as solvent by using ultrasound with shorter synthesis time as compared to solvo-thermal method. The synthesized ZIF-67 crystals were characterized by XRD, SEM, TEM, FT-IR, N2 adsorption-desorption and TGA/DTA. It was found that the ZIF-67 crystals were highly stable up to 350°C (in air), and have shown high crystallinity with a uniform crystallite size of around 50 nm (TEM), BET surface area of 1363 m2/g and Langmuir surface area of 1912 m2/g. Methylene blue absorption and photocatalysis of ZIF-67 nano-material were investigated. The results indicated the material is capable to promote photocatalysis to treat methylene blue, furthermore, the effect was enhanced with the addition of H2O2

Synthesis of Ordered Mesoporous TiO2 by Hydrolysis Condensation with Block Copolymer P123 as Template

2010 ◽  
Vol 113-116 ◽  
pp. 2119-2123
Author(s):  
Yan Wang ◽  
Qing Bai ◽  
Xuan Dong Li ◽  
Ai Hua Wen
Keyword(s):  
Block Copolymer ◽  
Decisive Role ◽  
Soxhlet Extraction ◽  
Mesoporous Structure ◽  
Bet Surface Area ◽  
Condensation Process ◽  
Template Removal ◽  
Ordered Mesoporous ◽  
Ft Ir ◽  
Adsorption Desorption

Highly ordered mesoporous TiO2 was synthesized by a hydrolysis condensation process using block copolymer P123 as the template and tetrabutyl orthotitanate (TBOT) as titanium precursor.The influences of the synthesis parameters including the volume of solvent, the ratio of the template to TBOT and reaction pH on the structure were investigated. The structure properties of the products were characterized with low-angle XRD, FT-IR, N2 adsorption-desorption analysis. The results showed that the amount of solvent played a decisive role for the formation of ordered pore structure. The proper hydrolysis pH is in neutral and acidic range. The template can be removed totally by Soxhlet extraction with ethanol and the mesoporous structure can be retained perfectly by this template removal method. The product has the BET surface area of 266.5m2/g and a narrow pore distribution with a peak at 4.34 nm.

MgAl2O4 spinel-type as highly efficient catalyst for one-pot synthesis of 4H-pyrans

2022 ◽  
Vol 16 ◽  
Author(s):  
Mustapha Dib ◽  
Marieme Kacem ◽  
Soumaya Talbi ◽  
Hajiba Ouchetto ◽  
Khadija Ouchetto ◽  
...  
Keyword(s):  
Ethyl Acetoacetate ◽  
Room Temperature ◽  
Aromatic Aldehydes ◽  
Molar Ratio ◽  
Green Solvents ◽  
N2 Adsorption ◽  
One Pot ◽  
Ft Ir ◽  
The One ◽  
Adsorption Desorption

Background: Pyran is an heterocyclic oxygen-containing compound that displays a wide range of therapeutic activities. Additionally, pyran is also one of the important structural subunits widely found in pharmaceuticals products. This makes it a recent focus for researchers from the industry and academic institutions. Herein, we reported an efficient and environmentally friendly one-pot strategy for the synthesis of bioactive 4H-pyran compounds via a multicomponent reaction of ethyl acetoacetate, malononitrile and substituted aromatic aldehydes in the presence of the heterogeneous spinel catalyst ( MgAl2O4 ) under mild conditions (room temperature and green solvents). The MgAl2O4 nanocatalyst was prepared from Mg/Al-LDH with a molar ratio 3 of Mg2+/Al3+ by heat treatment at 800°C. The samples were studied by a various characterization techniques such as XRD, TG-dTG, FT-IR and N2 adsorption-desorption. Good to excellent yields and facile separation of the catalyst from the reaction mixture are two of the most appealing features of this approach. Thus, bioactive molecules with pyran units may have fascinating biological properties. An efficient and green strategy for the one-pot synthesis of bioactive 4H-pyran compounds has been described. The pyrans heterocycles were produced by multicomponent reaction of ethyl acetoacetate, malononirile and substituted aromatic aldehydes in the presence of MgAl2O4 spinel nanocatalyst under mild conditions (room temperature and green solvents). MgAl2O4 nanocatalytst was prepared from Mg/Al-LDH with a molar ratio 3 of Mg2+/Al3+ by thermal treatment at 800°C. The samples were investigated by various characterization techniques such as XRD, TG-dTG, FT-IR and N2 adsorption-desorption. The following are the appealing qualities of this unique strategy including good to exceptional yields, and ease of separation of catalyst from the reaction mixture. Thus, the obtained bioactive compounds containing pyrans motif can be exhibiting interested biological activities. Methods: The substituted 4H-pyran compounds were carried out by condensation reaction of substituted aromatic aldehydes, ethyl ethyl acetoacetate and malononirile by using MgAl2O4 nanocatalyst under sustainable conditions. Objective: To develop an efficient methodology for synthesis of 4H-pyran heterocyclic molecules may have interesting applications in biology using a heterogeneous and easily synthesized catalyst. Results: This procedure outlines the synthesis of bioactive compounds in good yields and with ease of catalyst extraction from the reaction mixture under sustainable reaction conditions. Conclusion: In conclusion, it is important to reiterate that a spinel nanostucture has been successfully prepared and fully characterized using different physicochemical analysis methods. The catalytic activity of this heterogeneous catalyst was examined through the one-pot condensation of aryl benzaldehyde, malononitrile and ethyl acetoacetate. Therefore, we have developed a green method for the preparation of 4H-pyrans derivatives using MgAl2O4 as an efficient heterogeneous catalyst. The reactions were performed under green conditions, which have many benefits such as undergoing a simple procedure, good to excellent yields and easy to separate the catalyst.

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