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Solid Acid Catalyst (solid + acid_catalyst)

Distribution by Scientific Domains
Chemistry84%

Selected Abstracts

ChemInform Abstract: Silica-Bonded S-Sulfonic Acid: An Efficient and Recyclable Solid Acid Catalyst for the Synthesis of 4,4,-(Arylmethylene)bis(1H-pyrazol-5-ols).

CHEMINFORM, Issue 18 2010
Khodabakhsh Niknam
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

ChemInform Abstract: Sulfamic Acid: An Efficient, Cost-Effective, and Reusable Solid Acid Catalyst for the Synthesis of 1,8-Naphthyridines under Solvent-Free Heating and Microwave Irradiation.

CHEMINFORM, Issue 6 2009
Y. Thirupathi Reddy
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

ChemInform Abstract: Silica Sulfuric Acid as an Efficient Solid Acid Catalyst for Friedel,Crafts Acylation Using Anhydrides.

CHEMINFORM, Issue 10 2008
A. Alizadeh
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Facile Synthesis of 1,1-Diacetates from Aldehydes Using Environmentally Benign Solid Acid Catalyst under Solvent-Free Conditions.

CHEMINFORM, Issue 41 2004
Benjaram M. Reddy
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Eco-Friendly WO3,ZrO2 Solid Acid Catalyst for Acetylation of Alcohols and Phenols.

CHEMINFORM, Issue 52 2002
Benjaram M. Reddy
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Novel Solid Acid Catalysts: Sulfonic Acid Group-Functionalized Mesostructured Polymers,

ADVANCED FUNCTIONAL MATERIALS, Issue 14 2007
R. Xing
Abstract Novel solid acid catalysts have been prepared from Fudan University (FDU)-type mesoporous polymers with the Ia d and P6mm mesostructures through a carefully controlled sulfonation procedure. Various techniques have been adopted to characterize throughout their structures, porosity, acidity as well as the information related to the sulfonic acid groups. The sulfonic acid group-functionalized mesopolymers prove to be efficient heterogeneous catalysts in the reactions such as liquid-phase Beckmann rearrangement of cyclohexanone oxime and condensation of ethylene glycol with the aldehydes having different molecular sizes. [source]

Conversion of Furfuryl Alcohol into Ethyl Levulinate using Solid Acid Catalysts

CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 5 2009
Jean-Paul Lange Dr.
Abstract Cellulosic biofuel: Ethyl levulinate is a promising biofuel that can be obtained from lignocellulosic residues. A byproducts, furfural, can be converted into ethyl levulinate in an acid-based process. Here, the use of solid acid catalysts for the conversion of furfuryl alcohol into ethyl levulinate is reported. Furfural, a potential coproduct of levulinic acid, can be converted into levulinic acid via hydrogenation to furfuryl alcohol and subsequent ethanolysis to ethyl levulinate. The ethanolysis reaction is known to proceed in the presence of H2SO4. We show here that several strongly acidic resins are comparably effective catalysts for this reaction. Optimal performance is achieved by balancing the number of acid sites with their accessibility in the resin. Acidic zeolites such as H-ZSM-5 also catalyze this reaction, although with a lower activity and a higher coproduction of diethyl ether. [source]

Which Controls the Depolymerization of Cellulose in Ionic Liquids: The Solid Acid Catalyst or Cellulose?

CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 2 2010
Roberto Rinaldi Dr.
Abstract Cellulose is a renewable and widely available feedstock. It is a biopolymer that is typically found in wood, straw, grass, municipal solid waste, and crop residues. Its use as raw material for biofuel production opens up the possibility of sustainable biorefinery schemes that do not compete with food supply. Tapping into this feedstock for the production of biofuels and chemicals requires,as the first-step,its depolymerization or its hydrolysis into intermediates that are more susceptible to chemical and/or biological transformations. We have shown earlier that solid acids selectively catalyze the depolymerization of cellulose solubilized in 1-butyl-3-methylimidazolium chloride (BMIMCl) at 100,°C. Here, we address the factors responsible for the control of this reaction. Both cellulose and solid acid catalysts have distinct and important roles in the process. Describing the depolymerization of cellulose by the equivalent number of scissions occurring in the cellulosic chains allows a direct correlation between the product yields and the extent of the polymer breakdown. The effect of the acid strength on the depolymerization of cellulose is discussed in detail. Practical aspects of the reaction, concerning the homogeneous nature of the catalysis in spite of the use of a solid acid catalyst, are thoroughly addressed. The effect of impurities present in the imidazolium-based ionic liquids on the reaction performance, the suitability of different ionic liquids as solvents, and the recyclability of Amberlyst 15DRY and BMIMCl are also presented. [source]

An Efficient Solid Acid Promoted Synthesis of Quinoxaline Derivatives at Room Temperature

CHINESE JOURNAL OF CHEMISTRY, Issue 6 2007
Shaabani Ahmad
Abstract Quinoxaline derivatives have been synthesized in a very short time with excellent yields by the condensation of 1,2-diamines with aliphatic or aromatic 1,2-dicarbonyl compounds or benzilmonoxime in the presence of silica sulfuric acid as a very inexpensive solid acid catalyst at room temperature. The recovery and reuse of the catalyst are also satisfactory. [source]

Novel Solid Acid Catalysts: Sulfonic Acid Group-Functionalized Mesostructured Polymers,

ADVANCED FUNCTIONAL MATERIALS, Issue 14 2007
R. Xing
Abstract Novel solid acid catalysts have been prepared from Fudan University (FDU)-type mesoporous polymers with the Ia d and P6mm mesostructures through a carefully controlled sulfonation procedure. Various techniques have been adopted to characterize throughout their structures, porosity, acidity as well as the information related to the sulfonic acid groups. The sulfonic acid group-functionalized mesopolymers prove to be efficient heterogeneous catalysts in the reactions such as liquid-phase Beckmann rearrangement of cyclohexanone oxime and condensation of ethylene glycol with the aldehydes having different molecular sizes. [source]

ChemInform Abstract: Four-Component, One-Pot Synthesis of Tetrasubstituted Imidazoles Using a Catalytic Amount of MCM-41 or p-TsOH.

CHEMINFORM, Issue 40 2010
Rahim Hekmat Shoar
Abstract Mesoporous silica (MCM-41) and TosOH are used as easy-to-handle solid acid catalysts under different optimized conditions. [source]

Which Controls the Depolymerization of Cellulose in Ionic Liquids: The Solid Acid Catalyst or Cellulose?

CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 2 2010
Roberto Rinaldi Dr.
Abstract Cellulose is a renewable and widely available feedstock. It is a biopolymer that is typically found in wood, straw, grass, municipal solid waste, and crop residues. Its use as raw material for biofuel production opens up the possibility of sustainable biorefinery schemes that do not compete with food supply. Tapping into this feedstock for the production of biofuels and chemicals requires,as the first-step,its depolymerization or its hydrolysis into intermediates that are more susceptible to chemical and/or biological transformations. We have shown earlier that solid acids selectively catalyze the depolymerization of cellulose solubilized in 1-butyl-3-methylimidazolium chloride (BMIMCl) at 100,°C. Here, we address the factors responsible for the control of this reaction. Both cellulose and solid acid catalysts have distinct and important roles in the process. Describing the depolymerization of cellulose by the equivalent number of scissions occurring in the cellulosic chains allows a direct correlation between the product yields and the extent of the polymer breakdown. The effect of the acid strength on the depolymerization of cellulose is discussed in detail. Practical aspects of the reaction, concerning the homogeneous nature of the catalysis in spite of the use of a solid acid catalyst, are thoroughly addressed. The effect of impurities present in the imidazolium-based ionic liquids on the reaction performance, the suitability of different ionic liquids as solvents, and the recyclability of Amberlyst 15DRY and BMIMCl are also presented. [source]

Conversion of Furfuryl Alcohol into Ethyl Levulinate using Solid Acid Catalysts

CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 5 2009
Jean-Paul Lange Dr.
Abstract Cellulosic biofuel: Ethyl levulinate is a promising biofuel that can be obtained from lignocellulosic residues. A byproducts, furfural, can be converted into ethyl levulinate in an acid-based process. Here, the use of solid acid catalysts for the conversion of furfuryl alcohol into ethyl levulinate is reported. Furfural, a potential coproduct of levulinic acid, can be converted into levulinic acid via hydrogenation to furfuryl alcohol and subsequent ethanolysis to ethyl levulinate. The ethanolysis reaction is known to proceed in the presence of H2SO4. We show here that several strongly acidic resins are comparably effective catalysts for this reaction. Optimal performance is achieved by balancing the number of acid sites with their accessibility in the resin. Acidic zeolites such as H-ZSM-5 also catalyze this reaction, although with a lower activity and a higher coproduction of diethyl ether. [source]