X-ray diffraction studies of freezing and melting of water confined in a mesoporous adsorbent (MCM-41)

1997 ◽  
Vol 107 (17) ◽  
pp. 6965-6969 ◽  
Author(s):  
K. Morishige ◽  
K. Nobuoka
Keyword(s):  
X Ray Diffraction ◽  
X Ray ◽  
Mesoporous Adsorbent ◽  
Mcm 41

Diffuse wall structure and narrow mesopores in highly crystalline MCM-41 materials studied by X-ray diffraction

1997 ◽  
Vol 93 (1) ◽  
pp. 199-202 ◽  
Author(s):  
Karen J. Edler ◽  
Philip A. Reynolds ◽  
John W. White ◽  
David Cookson
Keyword(s):  
Wall Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mcm 41

scholarly journals ZnFe2O4-TiO2Nanoparticles within Mesoporous MCM-41

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Aidong Tang ◽  
Yuehua Deng ◽  
Jiao Jin ◽  
Huaming Yang
Keyword(s):  
Sol Gel ◽  
Rutile Phase ◽  
Band Gap Energy ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Agglomeration Of Nanoparticles ◽  
Adsorption Desorption ◽  
Mcm 41

A novel nanocomposite ZnFe2O4-TiO2/MCM-41 (ZTM) was synthesized by a sol-gel method and characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), N2adsorption-desorption, Raman spectroscopy, and ultraviolet visible (UV-vis) spectrophotometry. The results confirmed the incorporation of ZnFe2O4-TiO2nanoparticles inside the pores of the mesoporous MCM-41 host without destroying its integrity. ZnFe2O4nanoparticles can inhibit the transformation of anatase into rutile phase of TiO2. Incorporation of ZnFe2O4-TiO2within MCM-41 avoided the agglomeration of nanoparticles and reduced the band gap energy of TiO2to enhance its visible light photocatalytic activity. UV-vis absorption edges of ZTM nanocomposites redshifted with the increase of Zn/Ti molar ratio. The nanocomposite approach could be a potential choice for enhancing the photoactivity of TiO2, indicating an interesting application in the photodegradation and photoelectric fields.

Determination of the Lamellar Phase Content in MCM-41 Using X-ray Diffraction, Nitrogen Adsorption, and Thermogravimetry

2000 ◽  
Vol 104 (7) ◽  
pp. 1581-1589 ◽  
Author(s):  
Michal Kruk ◽  
Mietek Jaroniec ◽  
Yong Yang ◽  
Abdelhamid Sayari
Keyword(s):  
Nitrogen Adsorption ◽  
Lamellar Phase ◽  
Phase Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mcm 41

Time-resolved in situ X-ray diffraction study of MCM-41 structure formation from a homogeneous environment

1999 ◽  
Vol 1 (12) ◽  
pp. 3053-3057 ◽  
Author(s):  
Jiří Rathouský ◽  
Günter Schulz-Ekloff ◽  
Jiří Had ◽  
Arnošt Zukal
Keyword(s):  
Diffraction Study ◽  
Structure Formation ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Mcm 41 ◽  
Homogeneous Environment

Comparison of TiO2/RH-MCM-41 and TiO2/TEOS-MCM-41 Hybrid Catalysts in Characteristics and Photodegradation of Tetramethylammonium

2010 ◽  
Vol 93-94 ◽  
pp. 22-26 ◽  
Author(s):  
Surachai Artkla ◽  
Won Yong Choi ◽  
Jatuporn Wittayakun
Keyword(s):  
Irradiation Time ◽  
Catalytic Performance ◽  
X Ray Diffraction ◽  
N2 Adsorption ◽  
X Ray ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
Adsorption Desorption ◽  
Two Hybrid ◽  
Mcm 41

This work compared properties and catalytic performance of two hybrid photocatalysts, TiO2/RH-MCM-41 and TiO2/TEOS-MCM-41 prepared by loading nanoparticles of TiO2 (10 wt.%) on MCM-41 synthesized with rice husk silica and tetraethyl orthosilicate respectively. The supports and catalysts were characterized by X-ray diffraction, N2 adsorption-desorption, transmission electron microscopy and zeta potential. The photocatalytic activities of the TiO2/RH-MCM-41 and TiO2/TEOS-MCM-41 for the degradation of tetramethylammonium (TMA) in aqueous slurry were similar with a complete conversion after irradiation time of 90 min at pH 7.

Synthesis and Characterization of Mesoporous Molecular Sieve Al-MCM-41 Using Kaolin as Raw Material

2013 ◽  
Vol 779-780 ◽  
pp. 201-204
Author(s):  
Miao Li ◽  
Hong Wang ◽  
Xian Qing Li ◽  
Jin Rong Liu
Keyword(s):  
Molecular Sieve ◽  
Nitrogen Adsorption ◽  
Mesoporous Molecular Sieve ◽  
Raw Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Adsorption Desorption ◽  
Calcined Kaolin ◽  
Mcm 41

Ordered hexagonally mesoporous molecular sieve Al-MCM-41 with Si/Al (atom) ratio=9 was prepared by hydrothermal synthesis using raw kaolin. X-ray diffraction (XRD), Nitrogen adsorption desorption, Transmission Electron Microscope (TEM) and Energy Dispersive X-ray Detector (EDX) were employed to characterise raw kaolin, calcined kaolin, as-synthesized and calcined Al-MCM-41. The results indicated that characteristic reflections of raw kaolin disappeared after calcination, both of as-synthesized and calcined Al-MCM-41 exhibited well ordered hexagonally mesoporous molecular sieve structure.

scholarly journals Effect of CoMo/HSO3-functionalized MCM-41 over Heavy Oil

2019 ◽  
Vol 54 (4) ◽  
Author(s):  
Persi Schacht ◽  
Julia Aguilar-Pliego ◽  
Marco Ramírez-Garnica ◽  
Sergio Ramírez ◽  
Ibrahim Abu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Gulf Of Mexico ◽  
Specific Surface ◽  
Heavy Oil ◽  
Pore Channel ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
X Ray ◽  
Infra Red ◽  
Mcm 41

The potential of Co-Mo metals supported on functionalized MCM-41 as catalyst to hydrodesulfurization of heavy oil has been explored in this work. The MCM-41 functionalized sample was synthesized according to methods previously reported in the literature. Co and Mo metals were incorporated into the support by simultaneous impregnation. The catalyst was characterized by specific Surface area and X-Ray Diffraction. The pore channel of MCM-41 was confirmedby transmission electronic microscopy and infra red spectroscopy. Catalytic activity tests were carried out using heavy oil from Gulf of Mexico. The API gravity was increased from 12.5 to 20.2, the kinematics viscosity was decreased from 18,700 to 110 cSt at 298 K, the contents of asphaltene and sulfur were also reduced.  

New Routes Study for Synthesis of Molecular Sieves Type Al-MCM-41 and Al-SBA-15

2012 ◽  
Vol 727-728 ◽  
pp. 1222-1227
Author(s):  
Rafaela Pereira Roque de Miranda ◽  
José Otávio Peroba Nascimento Santos ◽  
José Jailson Nicácio Alves ◽  
Romildo Pereira Brito ◽  
Bianca Viana de Sousa
Keyword(s):  
Molecular Sieves ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Application ◽  
Silica Source ◽  
New Synthesis ◽  
Different Temperatures ◽  
Synthesis Routes ◽  
Mcm 41 ◽  
Great Development

The areas of research, synthesis and catalytic application of zeolites as molecular sieves are a field of great development and prominence in recent decades. Needs of the industries of petrochemical and fine chemicals have been encouraging specific studies for the application of molecular sieves looking for technological, commercial, and more recently sustainable developments. In this work molecular sieves type Al-MCM-41 and Al-SBA-15 has been synthesized using new synthesis routes by replacing the silica source conventionally used by rice husk. The molecular sieves obtained were confirmed by X-ray diffraction. Through the thermograms the decomposition of the driver at different temperatures was noticed. According to SEM micrographs can be observed that the material shows an aggregate of relatively uniform short particles.

Synthesis of SBA-15/MCM-41 bimodal mesoporous silica

2016 ◽  
Vol 1817 ◽  
Author(s):  
Leyla Y. Jaramillo ◽  
Wilson A. Henao ◽  
Elizabeth Pabón-Gelves
Keyword(s):  
Mesoporous Silica ◽  
Textural Properties ◽  
New Materials ◽  
X Ray Diffraction ◽  
Main Interest ◽  
Structure Directing Agent ◽  
X Ray ◽  
Synthesis Parameters ◽  
Nanostructured Silica ◽  
Mcm 41

ABSTRACTNanostructured silica materials with different morphologies and adjustable pore size have been studied by researches worldwide for several applications such as catalysis, separation, adsorption, and templates for new materials. The main interest in the development of these materials is to obtain a structure with a specific combination of pore sizes for a particular application. The morphology and textural properties of pores can be easily changed with the modification of the synthesis parameters, among these, the choice of surfactant or structure directing agent (SDA).Accordingly, in this work, three types of nanostructured silica with different mesoporosity were synthesized by using of CTAB and Pluronic 123 as structure directing agents: SBA-15 and MCM-41 unimodal mesoporous silica and SBA-15/MCM-41 bimodal mesoporous silica.To evaluate the effect of surfactant on the morphology and textural properties of pores, the materials were characterized by scanning electron microscopy (SEM), X-ray Diffraction (XRD) and nitrogen sorption (BET).

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