Microporous Silicon Nitride-Based Solid Bases

1998 ◽  
Vol 549 ◽  
Author(s):  
J. S. Bradley ◽  
O. Vollmer ◽  
R. Rovai ◽  
F. Lefebvre
Keyword(s):  
Surface Area ◽  
Condensation Reaction ◽  
High Surface ◽  
High Surface Area ◽  
Organic Content ◽  
Gaseous Ammonia ◽  
Solid Base ◽  
Solid Base Catalysts ◽  
Base Catalysts ◽  
Knoevenagel Condensation Reaction

AbstractHigh surface area, microporous, amorphous silicon imidonitride, characterized by infrared spectroscopy, MAS 29Si NMR and surface area and porosity measurements has been prepared by the treatment of co-oligomers of methylsilazane and dimethyl silazanes with gaseous ammonia at temperatures up to 700°C. The material has a narrow pore-size distribution showing a maximum in the range associated with wide- pore zeolites (ca. 0.72 nm mean). Variation of the organic content of the silazane is a means of controlling the surface area of the resulting solid. The Knoevenagel condensation reaction of benzaldehyde with a series of active methylene compounds has been used to probe the basicity and size-selectivity of these microporous solid base catalysts.

scholarly journals Layered double hydroxide anchored ionic liquids as amphiphilic heterogeneous catalysts for the Knoevenagel condensation reaction

2018 ◽  
Vol 47 (9) ◽  
pp. 3059-3067 ◽  
Author(s):  
Tengfei Li ◽  
Wei Zhang ◽  
Wei Chen ◽  
Haralampos N. Miras ◽  
Yu-Fei Song
Keyword(s):  
Heterogeneous Catalysts ◽  
Knoevenagel Condensation ◽  
Condensation Reaction ◽  
Knoevenagel Reaction ◽  
Solid Base ◽  
Solid Base Catalysts ◽  
Base Catalysts ◽  
Excellent Activity ◽  
Knoevenagel Condensation Reaction ◽  
Double Hydroxide

In this paper, three solid base catalysts of LDH-IL-Cn (n = 4, 8, 12) were synthesized by adopting an exfoliation/assembly approach. The as-prepared catalyst showed excellent activity and selectivity for the Knoevenagel reaction in aqueous solution.

Effects of ball-milling treatment on physicochemical properties and solid base activity of hexagonal boron nitrides

2019 ◽  
Vol 9 (2) ◽  
pp. 302-309 ◽  
Author(s):  
Shoichiro Namba ◽  
Atsushi Takagaki ◽  
Keiko Jimura ◽  
Shigenobu Hayashi ◽  
Ryuji Kikuchi ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Physicochemical Properties ◽  
Ball Milling ◽  
Surface Area ◽  
Hexagonal Boron Nitride ◽  
Solid Base ◽  
Solid Base Catalysts ◽  
Base Catalysts ◽  
Boron Nitrides

Hexagonal boron nitride solid base catalysts were prepared by simple ball-milling at various rotation speeds of a commercial low-surface area boron nitride.

Novel Base Catalysts by Nitridation of Zeolite Y: Characterization and Catalytic Evaluation

2010 ◽  
Vol 148-149 ◽  
pp. 1096-1099
Author(s):  
Gong Ming Peng ◽  
De Lian Yi ◽  
Lin Wu ◽  
Zhao Hui Ou Yang ◽  
Jian Guo Wang
Keyword(s):  
Surface Area ◽  
Zeolite Y ◽  
High Surface ◽  
High Surface Area ◽  
Diethyl Malonate ◽  
Bet Surface Area ◽  
In Situ Drifts ◽  
Base Catalysts ◽  
Diffuse Reflectance Infrared

Novel base catalysts were obtained by subjecting Y zeolites to nitridation. These materials were characterized by elemental analysis, X-ray diffraction, BET surface area analysis, In situ diffuse reflectance infrared fourier transform Spectroscopy (in situ DRIFTS), Pyrrole adsorption. The results indicated nitrogen-incorporated NaY zeolite was well ordered and possess high surface area and pore volume. In situ DRIFTS experiments confirmed that N atoms had been introduced into the framework by nitridation to form -NH2- or -NH- species. It was found that Lewis basicity of these oxynitride materials increased by the pyrrole adsorption. Furthmore, the basic catalytic properties of nitrogen-incorporated zeolites were evaluated by Knoevenagal condensation of benzaldehyde with diethyl malonate and enhanced yield of product was achieved.

Hierarchical flowerlike magnesium oxide hollow spheres with extremely high surface area for adsorption and catalysis

2016 ◽  
Vol 4 (2) ◽  
pp. 400-406 ◽  
Author(s):  
Shuliang Yang ◽  
Peipei Huang ◽  
Li Peng ◽  
Changyan Cao ◽  
Yanan Zhu ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Surface Area ◽  
Magnesium Oxide ◽  
Heavy Metal Ions ◽  
Catalytic Properties ◽  
Condensation Reaction ◽  
High Surface ◽  
Hollow Spheres ◽  
High Surface Area ◽  
Adsorption Properties

3D hierarchical flowerlike MgO hollow spheres with extremely high surface area showed excellent adsorption properties for heavy metal ions and catalytic properties for the Claisen–Schmidt condensation reaction.

scholarly journals Robust Amino-Functionalized Mesoporous Silica Hollow Spheres Templated by CO2 Bubbles

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 53
Author(s):  
Hongjuan Wang ◽  
Xuefei Liu ◽  
Olena Saliy ◽  
Wei Hu ◽  
Jingui Wang
Keyword(s):  
Mesoporous Silica ◽  
Condensation Reaction ◽  
High Surface ◽  
Hollow Spheres ◽  
High Surface Area ◽  
Production Costs ◽  
Hollow Structures ◽  
Functionalized Mesoporous Silica ◽  
Hollow Silica Spheres ◽  
Knoevenagel Condensation Reaction

Hollow-structured mesoporous silica has wide applications in catalysis and drug delivery due to its high surface area, large hollow space, and short diffusion mesochannels. However, the synthesis of hollow structures usually requires sacrificial templates, leading to increased production costs and environmental problems. Here, for the first time, amino-functionalized mesoporous silica hollow spheres were synthesized by using CO2 gaseous bubbles as templates. The assembly of anionic surfactants, co-structure directing agents, and inorganic silica precursors around CO2 bubbles formed the mesoporous silica shells. The hollow silica spheres, 200–400 nm in size with 20–30 nm spherical shell thickness, had abundant amine groups on the surface of the mesopores, indicating excellent applications for CO2 capture, Knoevenagel condensation reaction, and the controlled release of Drugs.

Synthesis, characterization, and base–catalytic performance of ordered mesoporous aluminophosphate oxynitride materials

2007 ◽  
Vol 22 (12) ◽  
pp. 3330-3337 ◽  
Author(s):  
Jiacheng Wang ◽  
Qian Liu
Keyword(s):  
Nitrogen Content ◽  
Condensation Reaction ◽  
High Surface ◽  
Physicochemical Characterization ◽  
Catalytic Performance ◽  
Solid Base ◽  
Base Materials ◽  
Ordered Mesoporous ◽  
Knoevenagel Condensation Reaction ◽  
And Control

The synthesis, physicochemical characterization, and catalytic evaluation of ordered mesoporous aluminophosphate oxynitride (MAPN) materials are presented here. The solid-base materials were prepared through treating aluminophosphate with an ordered mesostructure with ammonia at high temperatures. The MAPNs are well ordered, and possess high surface and pore volume. The amount of nitrogen incorporated increased with prolonged nitridation times. At the same time, the intensity of basicity is consistent with the nitrogen content, which is affirmed by Knoevenagel condensation reaction. The obtained ordered MAPN materials also possess acidity. The easy preparation and control of the nitrogen content of ordered MAPN materials, providing acidity and basicity, make them attractive as alternatives to a solid-base or acid-base catalyst, especially for the interactions of large molecules.

Synthesis of high surface area mixed metal oxide from the NiMgAl LDH precursor for nitro-aldol condensation reaction

2015 ◽  
Vol 39 (1) ◽  
pp. 172-178 ◽  
Author(s):  
Dipshikha Bharali ◽  
Rasna Devi ◽  
Pankaj Bharali ◽  
Ramesh C. Deka
Keyword(s):  
Metal Oxide ◽  
Surface Area ◽  
Mixed Oxide ◽  
Room Temperature ◽  
Aldol Condensation ◽  
Condensation Reaction ◽  
High Surface ◽  
High Surface Area ◽  
Mixed Metal Oxide ◽  
Solvent Free Conditions

NiMgAl mixed oxide catalyzes nitro-aldol condensation reaction at room temperature under solvent free conditions exhibiting 99% conversion.

High Surface Area Silicon Imidonitrides: A New Class of Microporous Solid Base

1998 ◽  
Vol 10 (12) ◽  
pp. 938-942 ◽  
Author(s):  
John S. Bradley ◽  
Oliver Vollmer ◽  
Riccardo Rovai ◽  
Ullrich Specht ◽  
Frédéric Lefebvre
Keyword(s):  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Solid Base ◽  
New Class
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