Nitric acid catalyzed hydrolysis of SO3 in the formation of sulfuric acid: A theoretical study

The sulfuric acid catalyzed acylation of 2-methyl-5-nitroisocarbostyril with carboxylic acid anhydrides gave the corresponding 4-acylated derivatives 3, which underwent reductive cyclization to 2-substituted derivatives of 4-methyl-1,3,4,5-tetrahydropyrrolo[4.3.2.de]isoquinolin-5-one (4). Alkaline hydrolysis of the six-membered lactam in 4 was accompanied by a retro-Mannich reaction to produce 2-substituted indole-4-carboxylic acids in about 40 % overall yield from 3.

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Theoretical Study of Acid-Catalyzed Hydrolysis of Epoxides

The Journal of Physical Chemistry A ◽

10.1021/jp9106316 ◽

2010 ◽

Vol 114 (15) ◽

pp. 5187-5194 ◽

Cited By ~ 20

Author(s):

Raimundo Clecio Dantas Muniz Filho ◽

Samuel Anderson Alves de Sousa ◽

Flávia da Silva Pereira ◽

Márcia Miguel Castro Ferreira

Keyword(s):

Theoretical Study ◽

Acid Catalyzed ◽

Hydrolysis Of

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Hydrothermal Pretreatment of Water-Extracted and Aqueous Ethanol-Extracted Quinoa Stalks for Enzymatic Saccharification of Cellulose

Energies ◽

10.3390/en14144102 ◽

2021 ◽

Vol 14 (14) ◽

pp. 4102

Author(s):

Cristhian Carrasco ◽

Leif J. Jönsson ◽

Carlos Martín

Keyword(s):

Sulfuric Acid ◽

Aqueous Ethanol ◽

Enzymatic Saccharification ◽

Product Formation ◽

Hydrothermal Pretreatment ◽

Raw Material ◽

Water Mixture ◽

Acid Catalyzed ◽

Preliminary Extraction ◽

Hydrolysis Of

Auto-catalyzed hydrothermal pretreatment (A-HTP) and sulfuric-acid-catalyzed hydrothermal pretreatment (SA-HTP) were applied to quinoa stalks in order to reduce their recalcitrance towards enzymatic saccharification. Prior to pretreatment, quinoa stalks were extracted with either water or a 50:50 (v/v) ethanol–water mixture for removing saponins. Extraction with water or aqueous ethanol, respectively, led to removal of 52 and 75% (w/w) of the saponins contained in the raw material. Preliminary extraction of quinoa stalks allowed for a lower overall severity during pretreatment, and it led to an increase of glucan recovery in the pretreated solids (above 90%) compared with that of non-extracted quinoa stalks (73–74%). Furthermore, preliminary extraction resulted in enhanced hydrolysis of hemicelluloses and lower by-product formation during pretreatment. The enhancement of hemicelluloses hydrolysis by pre-extraction was more noticeable for SA-HTP than for A-HTP. As a result of the pretreatment, glucan susceptibility towards enzymatic hydrolysis was remarkably improved, and the overall conversion values were higher for the pre-extracted materials (up to 83%) than for the non-extracted ones (64–69%). Higher overall conversion was achieved for the aqueous ethanol-extracted quinoa stalks (72–83%) than for the water-extracted material (65–74%).

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An Overview of Recent Developments in Hetero-Catalytic Conversion of Cellulosic Biomass

Research Communication in Engineering Science & Technology ◽

10.22597/rcest.v4.65 ◽

2020 ◽

Vol 4 ◽

pp. 43-54

Author(s):

Mohamed Rashid Ahmed-Haras ◽

Nhol Kao ◽

Md. Sakinul Islam ◽

Liam Ward

Keyword(s):

Sulfuric Acid ◽

Catalytic Conversion ◽

Cellulose Hydrolysis ◽

Nanocrystalline Cellulose ◽

Cellulosic Biomass ◽

Heterogeneous Catalytic ◽

Research Activities ◽

Acid Catalyzed ◽

Solid Acids Catalysts ◽

Hydrolysis Of

In recent years, research activities involved in the production of nanocellulosic materials have grown substantially, rapidly stimulating the development of innovative production techniques. These materials are chemically extracted by acid-catalyzed Hydrolysis of the renewable and widely available cellulosic biomass. In this regard, sulfuric acid-catalyzed Hydrolysis of cellulosic biomass is a commonly known method for the production of nanostructured cellulose. However, this method may result in many disadvantages, including short catalyst-lifetime, corrosive to the reactor materials and managing the spent sulfuric acid resulted from the production process. This dictates the implementation of an eco-industrial alternative for the catalytic production of nanocrystalline cellulose (NCC). A viable and practical alternative is the application of heterogeneous (solid acids) catalysts, which can be more conducive in providing favorable platforms for efficient cellulose hydrolysis. This review highlights the current production methods of nanocrystalline cellulose. Further, recent literature on the heterogeneous-catalytic conversion of cellulosic biomass is briefly discussed. The limitations and disadvantages of these techniques are also described.

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Formic Acid Catalyzed Hydrolysis of SO3in the Gas Phase: A Barrierless Mechanism for Sulfuric Acid Production of Potential Atmospheric Importance

Journal of the American Chemical Society ◽

10.1021/ja207393v ◽

2011 ◽

Vol 133 (43) ◽

pp. 17444-17453 ◽

Cited By ~ 94

Author(s):

Montu K. Hazra ◽

Amitabha Sinha

Keyword(s):

Sulfuric Acid ◽

Formic Acid ◽

Gas Phase ◽

Acid Production ◽

Sulfuric Acid Production ◽

Acid Catalyzed ◽

Hydrolysis Of

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Acid-catalyzed hydrolysis of benzoylhydrazine in sulfuric acid

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science ◽

10.1007/bf01094625 ◽

1981 ◽

Vol 30 (11) ◽

pp. 2044-2046

Author(s):

N. G. Zarakhan ◽

E. N. Borisova ◽

P. P. Nechaev ◽

G. E. Zaikov

Keyword(s):

Sulfuric Acid ◽

Acid Catalyzed ◽

Hydrolysis Of

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Silica sulfuric acid-catalyzed expeditious environment-friendly hydrolysis of carboxylic acid esters under microwave irradiation

Chemical Papers ◽

10.2478/s11696-008-0070-7 ◽

2008 ◽

Vol 62 (6) ◽

Cited By ~ 1

Author(s):

Zheng Li ◽

Jing Liu ◽

Xue Gong ◽

Xuerong Mao ◽

Xiunan Sun ◽

...

Keyword(s):

Sulfuric Acid ◽

Carboxylic Acid ◽

Microwave Irradiation ◽

High Yield ◽

Silica Sulfuric Acid ◽

Environment Friendly ◽

Acid Catalyzed ◽

Work Up ◽

Hydrolysis Of ◽

Acid Esters

AbstractSilica sulfuric acid was found to be an efficient, recoverable, reusable and environment-friendly catalyst for the fast hydrolysis of various carboxylic acid esters in high conversions and selectivities under microwave irradiation conditions. This protocol has the advantages of no corrosion, no environmental pollution, high reaction rate, high yield, and simple work-up procedure.

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