Eco-friendly synthesis for MCM-41 nanoporous materials using the non-reacted reagents in mother liquor

A new method of analysis of PALS spectra of porous materials is proposed. The model considers both the thermalization process of positronium inside the pores and the pore size distribution. The new model is fitted to spectra of mesoporous silica MCM-41 and MSF. The resulting parameters are compared with parameters obtained from fitting the “conventional” models, i.e. a sum of exponential components with discrete or/and distributed lifetimes.

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Solubility of Gases in Water Confined in Nanoporous Materials: ZSM-5, MCM-41, and MIL-100

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.5b06660 ◽

2015 ◽

Vol 119 (37) ◽

pp. 21547-21554 ◽

Cited By ~ 29

Author(s):

Linh Ngoc Ho ◽

Yves Schuurman ◽

David Farrusseng ◽

Benoit Coasne

Keyword(s):

Nanoporous Materials ◽

Solubility Of Gases ◽

Mcm 41

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Synthesis of Nanoporous Materials Al-MCM-41 from Natural Halloysite

NANO ◽

10.1142/s1793292015500058 ◽

2015 ◽

Vol 10 (01) ◽

pp. 1550005 ◽

Cited By ~ 8

Author(s):

Yaling Xie ◽

Aidong Tang ◽

Huaming Yang

Keyword(s):

Surface Area ◽

High Surface ◽

High Surface Area ◽

Halloysite Nanotubes ◽

Nanoporous Materials ◽

Molar Ratio ◽

Molar Ratios ◽

Naoh Solution ◽

The One ◽

Mcm 41

Nanoporous materials Al -MCM-41 with varying Si / Al molar ratios have been successfully synthesized from natural clay mineral halloysite nanotubes (HNTs). Hydrothermal treatment of acid-pretreated HNTs and NaOH solution resulted in the one-step synthesis of final nanoporous products by using surfactant. The effects of Si / Al molar ratios (7.7, 61.0 and 176.5) on the surface area, porosity and degree of structural order of Al -MCM-41 materials have been investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), N 2 adsorption–desorption measurements and Fourier transform infrared (FTIR) spectra techniques. The results indicated that Si / Al molar ratio had important effect on the characteristics of nanoporous materials, and Al -MCM-41 with an intermediate Si / Al molar ratio of 61.0 exhibited excellent characteristics with high degree of order, high surface area (S BET ) of 1033 m2/g and pore volume of 0.92 mL/g.

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Evidence of Anisotropic Self-Diffusion of Guest Molecules in Nanoporous Materials of MCM-41 Type

Journal of the American Chemical Society ◽

10.1021/ja001106x ◽

2000 ◽

Vol 122 (38) ◽

pp. 9237-9242 ◽

Cited By ~ 89

Author(s):

Frank Stallmach ◽

Jörg Kärger ◽

Cordula Krause ◽

Markus Jeschke ◽

Uwe Oberhagemann

Keyword(s):

Nanoporous Materials ◽

Guest Molecules ◽

Self Diffusion ◽

Mcm 41

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Catalytic Rapid Pyrolysis ofQuercus variabilisover Nanoporous Catalysts

Journal of Nanomaterials ◽

10.1155/2015/251974 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Hyeon Koo Kang ◽

In-Gu Lee ◽

Kyong-Hwan Lee ◽

Beom-Sik Kim ◽

Tae Su Jo ◽

...

Keyword(s):

Oil Quality ◽

Strong Acid ◽

Abundant Species ◽

Acid Sites ◽

Weak Acid ◽

Nanoporous Materials ◽

Bio Oil ◽

Strong Acid Sites ◽

Rapid Pyrolysis ◽

Mcm 41

Catalytic rapid pyrolysis ofQuercus variabilis, a Korean native tree species, was carried out using Py-GC/MS. Mesoporous MFI, which has both nanopores and micropores, and three nanoporous materials, Al-MCM-41, Al-SBA-15, andγ-Al2O3, were used as the catalyst. The acid sites of mesoporous MFI were strong Brønsted acid sites, whereas those of nanoporous materials were mostly weak acid sites. The composition of the product bio-oil varied greatly depending on the acid characteristics of the catalyst used. Phenolics were the most abundant species in the bio-oil, followed by acids and furanics, obtained over Al-MCM-41 or Al-SBA-15 with weak acid sites, whereas aromatics were the most abundant species produced over mesoporous MFI with strong acid sites, followed by phenolics. Aromatics, phenolics, and furanics are all important chemicals contributing to the improvement of bio-oil quality.

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Green Synthesis for MCM-41 and SBA-15 Silica Using the Waste Mother Liquor

10.21203/rs.3.rs-411718/v1 ◽

2021 ◽

Author(s):

Thianne Silva Batista Barbosa ◽

Thiago Rodrigo Barbosa Barros ◽

Tellys Lins Almeida Barbosa ◽

Meiry Gláucia Freire Rodrigues

Keyword(s):

Mesoporous Materials ◽

Mother Liquor ◽

Molecular Sieves ◽

Chemical Properties ◽

Physical And Chemical Properties ◽

X Ray ◽

Three Generations ◽

Physical And Chemical ◽

Mcm 41 ◽

And Chemical Properties

Abstract The synthesis of mesoporous materials such as MCM-41 and SBA-15 requires large amounts of water to neutralize the resulting products. The filtrate (mother liquor) therefore contains unreacted components that can be recycled and reused. The addition of the mother liquor in consecutive syntheses was carried out in order to evaluate the different effects on the physical and chemical properties of the mesoporous materials. For this purpose, the mother liquor from the initial synthesis (1st Generation) was saved and used for the second synthesis (2nd Generation) and successively for the third synthesis (3rd Generation). The three generations of each material were then characterized using different techniques such as X-ray diffraction, X-ray dispersive energy fluorescence, electron microscopy, infrared spectroscopy, Thermal behavior by thermogravimetric analysis and N2 adsorption. The materials obtained showed similar diffractograms for the three generations and also showed similar percentages of silica through XRF. The SEM and IR results for molecular sieves showed the effectiveness of the processes of MCM-41 and SBA-15 synthesis using mother liquor. The results made it possible to observe that the structures of the materials had no significant differences in their physical and chemical properties, favoring the use of mother liquor for up to three generations.

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