Vapor phase nitration of benzene over solid acid catalysts IV. Nitration with nitric acid (3); supported sulfuric acid catalyst with co-feeding of a trace amount of sulfuric acid

1999 ◽  
Vol 180 (1-2) ◽  
pp. 359-366 ◽  
Author(s):  
H Sato ◽  
K Nagai ◽  
H Yoshioka ◽  
Y Nagaoka
RSC Advances ◽  
2014 ◽  
Vol 4 (43) ◽  
pp. 22509-22519 ◽  
Author(s):  
Zhichao Miao ◽  
Huahua Zhao ◽  
Huanling Song ◽  
Lingjun Chou

A series of WO3 supported on ordered mesoporous zirconium oxophosphate solid acid catalyst was employed in benzylation reaction.


2021 ◽  
Vol 2 (4) ◽  
pp. 645-669
Author(s):  
Maksim Tyufekchiev ◽  
Jordan Finzel ◽  
Ziyang Zhang ◽  
Wenwen Yao ◽  
Stephanie Sontgerath ◽  
...  

A systematic and structure-agnostic method for identifying heterogeneous activity of solid acids for catalyzing cellulose hydrolysis is presented. The basis of the method is preparation of a supernatant liquid by exposing the solid acid to reaction conditions and subsequent use of the supernatant liquid as a cellulose hydrolysis catalyst to determine the effects of in situ generated homogeneous acid species. The method was applied to representative solid acid catalysts, including polymer-based, carbonaceous, inorganic, and bifunctional materials. In all cases, supernatant liquids produced from these catalysts exhibited catalytic activity for cellulose hydrolysis. Direct comparison of the activity of the solid acid catalysts and their supernatants could not provide unambiguous detection of heterogeneous catalysis. A reaction pathway kinetic model was used to evaluate potential false-negative interpretation of the supernatant liquid test and to differentiate heterogeneous from homogeneous effects on cellulose hydrolysis. Lastly, differences in the supernatant liquids obtained in the presence and absence of cellulose were evaluated to understand possibility of false-positive interpretation, using structural evidence from the used catalysts to gain a fresh understanding of reactant–catalyst interactions. While many solid acid catalysts have been proposed for cellulose hydrolysis, to our knowledge, this is the first effort to attempt to differentiate the effects of heterogeneous and homogeneous activities. The resulting supernatant liquid method should be used in all future attempts to design and develop solid acids for cellulose hydrolysis.


RSC Advances ◽  
2015 ◽  
Vol 5 (103) ◽  
pp. 84621-84626 ◽  
Author(s):  
Peixue Wang ◽  
Shimin Liu ◽  
Feng Zhou ◽  
Benqun Yang ◽  
Ahmad S. Alshammari ◽  
...  

Efficient synthesis of diphenyl carbonate from dibutyl carbonate and phenol using square-shaped Zn–Ti–O nanoplates as solid acid catalyst.


2017 ◽  
Vol 48 (2) ◽  
pp. 117 ◽  
Author(s):  
Yane Ansanay ◽  
Praveen Kolar ◽  
Ratna Sharma-Shivappa ◽  
Jay Cheng ◽  
Sunkyu Park ◽  
...  

There is a significant interest in employing solid acid catalysts for pre-treatment of biomasses for subsequent hydrolysis into sugars, because solid acid catalysts facilitate reusability, high activity, and easier separation. Hence the present research investigated pretreatment of four lignocellulosic biomasses, namely Switchgrass (Panicum virgatum L ‘Alamo’), Gamagrass (Tripsacum dactyloides), Miscanthus (Miscanthus × giganteus) and Triticale hay (Triticale hexaploide Lart.) at 90°C for 2 h using three carbon-supported sulfonic acid catalysts. The catalysts were synthesized via impregnating p-Toluenesulfonic acid on carbon (regular) and further impregnated with iron nitrate via two methods to obtain magnetic A and magnetic B catalysts. When tested as pre-treatment agents, a maximum total lignin reduction of 17.73±0.63% was observed for Triticale hay treated with magnetic A catalyst. Furthermore, maximum glucose yield after enzymatic hydrolysis was observed to be 203.47±5.09 mg g–1 (conversion of 65.07±1.63%) from Switchgrass treated with magnetic A catalyst. When reusability of magnetised catalysts were tested, it was observed that magnetic A catalyst was consistent for Gamagrass, Miscanthus × Giganteus and Triticale hay, while magnetic B catalyst was found to maintain consistent yield for switchgrass feedstock. Our results suggested that magnetised solid acid catalyst could pre-treat various biomass stocks and also can potentially reduce the use of harsh chemicals and make bioenergy processes environment friendly.


2017 ◽  
Vol 727 ◽  
pp. 438-444
Author(s):  
Xiang Ying Hao ◽  
Yu Li Zhang ◽  
Guan Hua Shen ◽  
Wen Sheng Wu

SO42-/ Al-Fe-activated solid acid catalysts had been prepared in different conditions using cross-linking method, and characterized by XRD, BET, FTIR spectra and TG-DTA. The catalyst performed highly catalytic activity in the hydration of turpentine to α-terpineol.


1984 ◽  
Vol 13 (12) ◽  
pp. 2047-2050 ◽  
Author(s):  
Kaoru Fujimoto ◽  
Tsutomu Shikada ◽  
Kohji Omata ◽  
Hiro-o Tominaga

1985 ◽  
Vol 16 (24) ◽  
Author(s):  
K. FUJIMOTO ◽  
T. SHIKADA ◽  
K. OMATA ◽  
H. TOMINAGA

RSC Advances ◽  
2015 ◽  
Vol 5 (127) ◽  
pp. 104715-104724 ◽  
Author(s):  
Avinash A. Chaugule ◽  
Amol R. Jadhav ◽  
Hern Kim

We have synthesized Brønsted solid acid catalysts which exhibited effective catalytic activity for acid catalyzed glycosylation reactions.


Synthesis ◽  
2021 ◽  
Author(s):  
Ken-ichi Itoh ◽  
Mamiko Hayakawa ◽  
Rina Abe ◽  
Shinji Takahashi ◽  
Kenta Hasegawa ◽  
...  

Nitrile oxides were obtained from α-nitro ketones by the use of silica-gel supported sodium hydrogensulfate (NaHSO4/SiO2) or Amberlyst 15 as solid acid catalyst, and then the corresponding 3-acylisoxaszoles were obtained from alkynes via the 1,3-dipolar ([3+2]) cycloaddition. These heterogeneous catalysts are easily separable from the reaction mixture, and reused up to the synthesis. This synthetic method provides a facile, efficient and reusable production of 3-acylisoxazoles.


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