Manganese Incorporation into the Mesoporous Material MCM-41 under Acidic Conditions as Studied by High Field Pulsed EPR and ENDOR Spectroscopies

2000 ◽  
Vol 122 (29) ◽  
pp. 7034-7041 ◽  
Author(s):  
Jingyan Zhang ◽  
Daniella Goldfarb
Keyword(s):  
Mesoporous Material ◽  
High Field ◽  
Pulsed Epr ◽  
Acidic Conditions ◽  
Mcm 41

scholarly journals Optimization of MCM-41 Mesoporous Material Mixed Matrix Polyethersulfone Membrane for Dye Removal

Membranes ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 414
Author(s):  
Rana J. Kadhim ◽  
Faris H. Al-Ani ◽  
Qusay F. Alsalhy ◽  
Alberto Figoli
Keyword(s):  
Membrane Fouling ◽  
Mesoporous Material ◽  
Optimization Technique ◽  
Operating Conditions ◽  
Mixed Matrix ◽  
Pareto Chart ◽  
Significance Level ◽  
Pes Membrane ◽  
Wasted Energy ◽  
Mcm 41

The aim of this work is the optimization of the operating conditions under which MCM-41-mesoporous material can be incorporated into polyethersulfone (PES)/MCM-41 membranes for nanofiltration (NF) applications. MCM-41 mesoporous material mixed matrix PES membranes have the potential to reduce membrane fouling by organic dye molecules. Process optimization and modeling aim to reduce wasted energy while maintaining high flow during the operation to handle the energy efficiency problems membranes often have. An optimization technique was applied to obtain optimum values for some key parameters in the process to produce a certain amount of flux above the desired values. Response surface methodology (RSM) and analysis of variance (ANOVA) were used as mathematical and statistical analyses to improve the performance of the process on a larger scale. This work investigated the influence of the operating parameters, such as the feed pH values (3–11), MCM-41 content (0–1 wt.%), and the feed dye concentration (10–100 ppm) for each of the two studied dyes, acid black 210 (AB-210) and rose bengal (RB), and their interactions on the PES membrane permeability. The results showed that the PES membrane had the best performance at 64.25 (L·m−2·h−1·bar-1) and 63.16 (L·m−2·h−1·bar-1) for the AB-210 and RB dyes, respectively. An MCM-41 content of nearly 0.8 wt.% in the casting solution, feed dye concentration of 10 ppm for the studied dyes, and feed pH of 3 for the RB dye was found to be the optimal parameters for eliciting the response. The pH had no significant influence on the response for the AB-210 dye, while the pH shows some minor effects on response with the RB dye, and the Pareto chart of the standardized effects on the permeation flux of both dyes using statistically significant at the 5% significance level support these results.

The effect of phosphate treatment on nickel dispersion on MCM-41 mesoporous material

2003 ◽  
Vol 20 (2) ◽  
pp. 256-261 ◽  
Author(s):  
Sung Soo Park ◽  
Sang Joon Choe ◽  
Dong Ho Park
Keyword(s):  
Mesoporous Material ◽  
Phosphate Treatment ◽  
Nickel Dispersion ◽  
Mcm 41

Use of Ionic Liquid as Template for Hydrothermal Synthesis of the MCM-41 Mesoporous Material

Silicon ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 289-294 ◽  
Author(s):  
José Arnaldo Santana Costa ◽  
Priscila Vedovello ◽  
Caio Marcio Paranhos
Keyword(s):  
Ionic Liquid ◽  
Hydrothermal Synthesis ◽  
Mesoporous Material ◽  
Mcm 41

Copolymerization of ethylene and non-conjugated diene with metallocene/methylaluminoxane system supported on MCM-41 mesoporous material

2004 ◽  
Vol 40 (11) ◽  
pp. 2555-2563 ◽  
Author(s):  
Daniela E.B. Lopes ◽  
Maria de Fátima V. Marques ◽  
Marcos L. Dias ◽  
Maria do Rosário Ribeiro ◽  
João P. Lourenço
Keyword(s):  
Mesoporous Material ◽  
Conjugated Diene ◽  
Mcm 41

Fast to Ultrafast Dynamics of Palladium Phthalocyanine Covalently Bonded to MCM-41 Mesoporous Material

2009 ◽  
Vol 113 (44) ◽  
pp. 19199-19207 ◽  
Author(s):  
Anna Synak ◽  
Michał Gil ◽  
Juan Angel Organero ◽  
Félix Sánchez ◽  
Marta Iglesias ◽  
...  
Keyword(s):  
Mesoporous Material ◽  
Ultrafast Dynamics ◽  
Covalently Bonded ◽  
Mcm 41

Effect of Synthesis Duration on the Physicochemical Properties of Siliceous Mesoporous Molecular Sieve (Si-MMS)

2012 ◽  
Vol 326-328 ◽  
pp. 647-653 ◽  
Author(s):  
Anita Ramli ◽  
Sohail Ahmed ◽  
Suzana Yusup
Keyword(s):  
Physicochemical Properties ◽  
Pore Structure ◽  
Molecular Sieve ◽  
Mesoporous Material ◽  
Mesoporous Molecular Sieve ◽  
Diffraction Peaks ◽  
Adsorption Desorption ◽  
Synthesized Materials ◽  
Synthesis Duration ◽  
Mcm 41

Pure silica mesoporous molecular sieve (MMS) solid has been synthesized at 100°C by hydrothermal process. The effect of synthesis duration from 2 to 10 days has been investigated on the physicochemical properties of mesoporous molecular sieve. Samples were characterized by low angle XRD, N2adsorption-desorption and HRTEM analysis. XRD patterns of the as-synthesized samples showed four well-defined diffraction peaks corresponding to 100, 110, 200 and 210 planes. These peaks are the fingerprint characteristics of MCM-41 mesoporous material. The high intensity diffraction peaks were observed in 8-days sample that define the high ordering of the pores and long range order. N2adsorption-desorption results showed that all samples possessed a type IV isotherm having hysteresis loop of typeH1which is an identification of mesoporous material. Calcined samples exhibited high surface area i.e., 984-1036 m2g-1, pore volume i.e., 1.00-1.13 cm3g-1and average pore diameter i.e., 3.04-3.30 nm. A hexagonal pore structure was found in the synthesized materials by HRTEM analysis, which confirms that the synthesized materials are MCM-41. HRTEM analysis showed the effect of synthesis duration on the materials and found that 8-days sample exhibited highly ordered hexagonal pore structure like honeycomb structure. All the samples were calcined at 550°C to remove the template and to study the changes in the mesoporous framework. The results showed that the mesoporous structure remained intact after calcination at 550°C, indicating that the mesoporous materials exhibit high thermal stability.

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