A Novel Iron Silicate Mesoporous Material Synthesis and Its Characterization

2018 ◽  
Vol 24 (8) ◽  
pp. 5532-5536
Author(s):  
M. A Mary Thangam ◽  
Chellapandian Kannan
Keyword(s):  
Mesoporous Materials ◽  
Molecular Sieves ◽  
Mesoporous Material ◽  
Synthesis Method ◽  
Acid Sites ◽  
Mesoporous Molecular Sieves ◽  
Isomorphous Substitution ◽  
Main Role ◽  
Material Synthesis ◽  
Ft Ir

The mesoporous materials have variety of applications in several field particularly it has a main role in Catalysis, Petrochemical industries and Adsorption. Normally the porous material has well ordered 3Dimensional structure, huge surface area, high thermal stability and active acid sites. The properties of these materials can be varied because it is mostly depends on its template, synthesis method and isomorphous substitution of metal ions. There are two major mesoporous materials which are aluminosilicate and aluminophosphate. In this present investigation AlCl3 and FeCl3 are used in equal amount for the synthesis of mesoporous material. The synthesized material is characterized by FT-IR, XRD, TGA, BET, EDAX and TPD. Morphological images were studied by SEM. These characterization techniques confirm the formation of mesoporous molecular sieves.

Modified mesoporous materials as Pd scavengers and catalyst supports

2007 ◽  
Vol 79 (2) ◽  
pp. 247-260 ◽  
Author(s):  
Cathleen M. Crudden ◽  
Kevin McEleney ◽  
Stephanie L. MacQuarrie ◽  
Alexandre Blanc ◽  
Mutyala Sateesh ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Mesoporous Materials ◽  
Molecular Sieves ◽  
Mesoporous Material ◽  
Mesoporous Molecular Sieves ◽  
Catalyst Supports ◽  
Heck Reactions ◽  
Ordered Mesoporous ◽  
Three Phase ◽  
Ordered Mesoporous Material

The use of mesoporous molecular sieves (MMSs) modified by mercaptopropyl trimethoxysilane (MPTMS) to scavenge Pd is described. The ordered mesoporous material displays excellent ability to remove Pd from organic and aqueous solutions. After only one treatment, a 500-ppm solution of PdCl2 in water can be reduced to 1 ppb. In addition, the resulting material is an effective, leach-proof catalyst for the Suzuki-Miyaura and Mizoroki-Heck reactions. Thus, the Suzuki-Miyaura reaction can be conducted in water at 80 °C with as little as 3 ppb Pd leaching. Hot filtrations and three-phase tests confirm that the catalyst acts without leaching Pd from the surface.

Adsorption of Carbon Dioxide into Amine Functionalized Ordered Mesoporous Materials

2018 ◽  
Author(s):  
Marcela N. Barbosa ◽  
Maria J. F. Costa ◽  
Maricele N. Barbosa ◽  
Valter J. Fernandes Jr. ◽  
Giancarlo R. Salazar-Banda ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Molecular Sieves ◽  
Synthesis Method ◽  
Mesoporous Molecular Sieves ◽  
Carbon Dioxide Adsorption ◽  
X Ray ◽  
Ordered Mesoporous ◽  
Mcm 41

The adsorption of carbon dioxide on amino silanes-functionalized MCM-41 and SBA-15 materials is reported. The functionalization of mesoporous silicas was made by post-synthesis method, by impregnation of 3-aminopropyltriethoxysilane. The obtained materials were characterized by X-ray diffraction, scanning and transmission electron microscopies, nitrogen adsorption-desorption and X-ray photoelectron spectroscopy measurements. The carbon dioxide adsorption capacities for the samples were carried out under ambient pressures. The obtained results evidenced that amino-silanes with a terminal amine (–NH2) were functionalized through covalent coupling of this group on the surface of the channels in the ordered mesoporous silica, meaning that the amine is anchored on the surface of the bigger pores of the MCM-41 and SBA-15 support. For functionalized materials, the CO2 adsorption capacity of the AMCM-41 increased from 0.18 to 1.1 mmol·g−1, whereas for ASBA-15, it was from 0.6 to 1.8 mmol·g−1. The Lagergren kinetic algorithms were applied in order to validate the obtained results, evidencing the enhanced carbon dioxide adsorption capacity and stability of the functionalized ordered mesoporous molecular sieves.

Oxidation of Higher Alkanes at Moderate Reaction Conditions with Ozone in Presence of Mesoporous Materials

2008 ◽  
Vol 11 (3) ◽  
Author(s):  
V. S. R. Rajasekhar Pullabhotla ◽  
S. B. Jonnalagadda
Keyword(s):  
Carboxylic Acids ◽  
Mesoporous Materials ◽  
Molecular Sieves ◽  
Mesoporous Molecular Sieves ◽  
Reaction Products ◽  
Reaction Conditions ◽  
Moderate Reaction ◽  
Product Molecule ◽  
Relative Selectivity ◽  
Mcm 41

AbstractThe scope of mesoporous molecular sieves, Al-MCM-41, as catalysts in the ozone initiated fuctionalisation of higher n-alkanes at 20 ± 1 °C and ~1 atm conditions is investigated. Oxygen is introduced into carbonaceous site in the product molecule forming 2-, 3- and 4- keto- isomers as main products and carboxylic acids as minor products. The % conversion, reaction products and selectivity for the catalysed reactions are compared. In presence of catalysts, the relative selectivity towards 4-ketone is increased.

Synthesis of Al-Containing Mesoporous Molecular Sieves and their Catalytic Performance to Isomerization Reaction of Endo-Tetrahydrodicyclo-Pentadiene

2011 ◽  
Vol 233-235 ◽  
pp. 234-237 ◽  
Author(s):  
Sa Liu ◽  
Jian Wei Guo ◽  
Chu Fen Yang ◽  
Long Huan Li ◽  
Yi Hua Cui
Keyword(s):  
Catalytic Activity ◽  
Molecular Sieves ◽  
Catalytic Performance ◽  
Mesoporous Molecular Sieves ◽  
Isomerization Reaction ◽  
Inorganic Acid ◽  
Ft Ir ◽  
Desorption Isotherms ◽  
Adsorption Desorption ◽  
Mcm 41

Al-containing mesoporous molecular sieves(Al-MCM-41) were synthesized at ambient temperature. The structures of samples were characterized by XRD, N2-adsorption/desorption isotherms and FT-IR, etc. The evaluation results showed that Al-MCM-41 had higher catalytic activity for isomerization conversion of endo-tetrahydrodicyclo-pentadiene (endo-TCD) into exo-tetrahydrodicyclo-pentadiene (exo-TCD) and adamantane (AdH). Loading inorganic acid on the surface of Al-MCM-41 led increase of its catalytic activity and the yield of adamantane.

Synthesis and Catalytic Application of Mesoporous Molecular Sieves MCM-41 Containing Niobium and Tantalum

2007 ◽  
Vol 124-126 ◽  
pp. 1761-1764 ◽  
Author(s):  
Hun Jung ◽  
Kwang Deog Jung ◽  
Oh Shim Joo ◽  
Sun Jin Kim
Keyword(s):  
Vapor Phase ◽  
Molecular Sieves ◽  
Catalytic Performance ◽  
Acid Sites ◽  
Weak Acid ◽  
Beckmann Rearrangement ◽  
Mesoporous Molecular Sieves ◽  
Cyclohexanone Oxime ◽  
Catalytic Application ◽  
Mcm 41

Niobium- and tantalum-containing mesoporous molecular sieves MCM-41 have been synthesized, and applied as a catalyst for vapor phase Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam. NbMCM-41 catalyst exhibited high catalytic performance in the vapor phase Beckmann rearrangement of cyclohexanone oxime. The oxime conversions were almost 100% and the lactam selectivities were around 80%. The lactam selectivities of NbMCM-41 catalyst were higher than those of AlMCM-41 catalyst. However, TaMCM-41 catalyst exhibited lower catalytic performance than AlMCM-41 catalyst, and it was fast deactivated with time. These results may be due to the acidity difference among the catalysts. The results from NH3-TPD showed that NbMCM-41 catalyst possessed weak and medium acid sites, while TaMCM-41 catalyst possessed only very weak acid sites. AlMCM-41 catalyst also exhibited only weak acid sites.

Rice Straw and Rice Straw Ash as Precursor for Synthesis of Mesoporous Molecular Sieves MCM-41

2012 ◽  
Vol 550-553 ◽  
pp. 1391-1394
Author(s):  
Xiao Hong Tang ◽  
Bao Jun Li ◽  
Cheng Wei Li
Keyword(s):  
Rice Straw ◽  
Molecular Sieves ◽  
Mesoporous Structure ◽  
Mesoporous Molecular Sieves ◽  
X Ray Diffraction ◽  
Ft Ir ◽  
Temperature Programmed ◽  
Adsorption Desorption ◽  
Straw Ash ◽  
Mcm 41

In this paper, rice straw (RS) and rice straw ash (RSA) were employed to synthesize mesoporous molecular sieves MCM-41 in an open-vessel. The structure of as-synthesized MCM-41 was characterized by X-ray diffraction (XRD) pattern, Fourier transform infrared (FT–IR) spectrum, NH3-Temperature Programmed Desorption (TPD), and N2 adsorption-desorption isotherms. RS-MCM-41 and RSA-MCM-41 possess the same typical hexagonal mesoporous structure with high long-range order and crystalline degree as those of MCM-41 from water glass (SDS-MCM-41).

The catalytic effect of boron substitution in MCM-41-type molecular sieves

2004 ◽  
Vol 82 (5) ◽  
pp. 631-640 ◽  
Author(s):  
V Sundaramurthy ◽  
I Eswaramoorthi ◽  
N Lingappan
Keyword(s):  
Molecular Sieves ◽  
Boron Content ◽  
Acid Sites ◽  
Mas Nmr ◽  
Catalyst Characterization ◽  
Secondary Products ◽  
Hydrogen Shift ◽  
Wide Range ◽  
Ft Ir ◽  
Mcm 41

A series of B-MCM-41 samples has been synthesized with a wide range of boron content (SiO2:B2O3 ratio from 20 to 200), using ethyl silicate ester-40 (ES-40) as the silica source and characterized by XRD, BET, FT-IR, 11B-MAS NMR, SEM, pyridine adsorption, TPDA, and chemical analysis. The interplanar d100 spacing varies from 40 to 45 Å, depending on the Si:B ratio. On calcination, a significant amount of four-coordinated boron is converted into less stable three-coordinated boron, and some boron is removed from the framework. The degree of deboronation increases with an increase of boron content of the sample. The B substitution in the MCM-41 framework results in only weak and mild acid sites. The isomerization of 1-hexene is found to be influenced by the boron content in the framework. The isomerization leads to both a hydrogen shift and skeletal rearrangement. The selectivity ratios of cis-2-hexene to trans-2-hexene and 2-hexene to 3-hexene were found to decrease with an increase of temperature and a decrease of the SiO2:B2O3 ratio of the catalysts. Skeletal isomerization starts at 250 °C, forming secondary products, and increases with an increase of temperature and an increase of boron content of the catalysts. Key words: ES-40, B-MCM-41, deboronation, catalyst characterization, XRD, BET, FT-IR, 11B-MAS NMR, SEM, 1-hexene isomerization, 2-hexene.

Effect of Silicon Sources on Self-Assembly in Acidic Environment and Impact on Morphology and Grain Size of Mesoporous Material

2007 ◽  
Vol 121-123 ◽  
pp. 465-468
Author(s):  
Song Chen ◽  
Yong Run Yang ◽  
Jin Dai Wang
Keyword(s):  
Mesoporous Materials ◽  
Self Assembly ◽  
Mesoporous Material ◽  
Hydrothermal Process ◽  
Material Synthesis ◽  
Acid Media ◽  
Silicon Source ◽  
Nanometer Material ◽  
Silicon Sources ◽  
Mcm 41

Alkaline hydrothermal process with using cetyl-trimenthylammonium bromide as template is typical method to prepare MCM-41 mesoporous material. Synthesis in acid media was seldom researched deeply. With cheap inorganic water glass, effect of different silicon sources on self-assembly in acid media was investigated. Not like typical MCM-41 mesoporous materials, it is found that results of analysis are a little different and morphology of mesoporous materials synthesized in acid media does not rely on silicon sources, regardless of organic or inorganic silicon source. It is also noticed that nanometer granule of mesoporous material can be directly made by simply adjusting water dosage, which open up a new way for preparing nanometer material by self-assembly.

Fe(III) Containing MCM-48 Type Mesoporous Molecular Sieves with Framework Zeolite Secondary Building Units

2008 ◽  
Vol 8 (1) ◽  
pp. 400-404 ◽  
Author(s):  
Ayyamperumal Sakthivel ◽  
Kenichi Komura ◽  
Yoshihiro Sugi
Keyword(s):  
Molecular Sieves ◽  
Membered Ring ◽  
Mesoporous Molecular Sieves ◽  
Secondary Building Unit ◽  
Tetrahedral Framework ◽  
Secondary Building Units ◽  
Ft Ir ◽  
Ir Analysis ◽  
Adsorption Desorption ◽  
First Time

Fe(III) containing mesoporous materials (FeMMSH) with zeolite building units were first time synthesized. XRD and N2 adsorption/desorption analysis confirm the mesoporous characters similar to MCM-48. FT-IR analysis of FeMMSH showed an additional band at about 530–550 cm− 1, characteristic of double five-membered ring of zeolite (ZSM-5) secondary building unit. The Fe(III) in FeMMSH materials is present in tetrahedral, and distorted tetrahedral framework are evident from EPR and DRUV-VIS spectra.

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