Adsorption of Perfluorooctanoic Acid From Water by pH-Modulated Brönsted Acid and Base Sites in Mesoporous Hafnium Oxide Ceramics

2021 ◽  
Author(s):  
Fatima A. Hussain ◽  
Maureen Kinyua ◽  
Jesus Velazquez
Keyword(s):  
Hafnium Oxide ◽  
Perfluorooctanoic Acid ◽  
Oxide Ceramics ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Brönsted Acid ◽  
Acid And Base

scholarly journals “Goldilocks Effect” of Water in Lewis-Brønsted Acid and Base Catalysis

ACS Catalysis ◽  
2016 ◽  
Vol 6 (7) ◽  
pp. 4189-4194 ◽  
Author(s):  
Benedict J. Barron ◽  
Wing-Tak Wong ◽  
Pauline Chiu ◽  
King Kuok Hii
Keyword(s):  
Base Catalysis ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Effect Of Water ◽  
Brönsted Acid ◽  
Acid And Base ◽  
Acid And Base Catalysis

Protic Ionic Liquids and Ionicity

2007 ◽  
Vol 60 (1) ◽  
pp. 21 ◽  
Author(s):  
Bharathi Nuthakki ◽  
Tamar L. Greaves ◽  
Irena Krodkiewska ◽  
Asoka Weerawardena ◽  
M. Iko Burgar ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Protic Ionic Liquids ◽  
Acid Base ◽  
Degree Of Ionization ◽  
Brönsted Acid ◽  
Acid And Base ◽  
Brønsted Base ◽  
Ir And Raman

Protic ionic liquids (PILs) are a subset of ionic liquids formed by the equimolar mixing of a Brønsted acid and a Brønsted base. PILs have been categorized as poor ionic liquids. However, the issue of assessing the ionicity of PILs is still a matter of debate. In this work we studied some physicochemical properties of three chosen PILs, namely, ethanolammonium acetate (EOAA), 2-methylbutylammonium formate (2MBAF), and pentylammonium formate (PeAF), at the initial equimolar (stoichiometric) acid/base ratio and in the presence of excess acid and base. DSC phase-transition studies along with NMR, IR, and Raman spectroscopy were performed on the chosen PILs. The results are discussed in terms of the degree of ionization (extent of proton transfer from the Brønsted acid to Brønsted base), and the possibility of the formation of polar 1:1 complexes and larger aggregates in the neat stoichiometric PILs.

Solvent-Free Acetalization of Glycerol with n-Octanal using Combined Brønsted Acid-Surfactant Catalyst

2017 ◽  
Vol 54 (1) ◽  
pp. 54-63 ◽  
Author(s):  
Xu Li ◽  
Lan Wu ◽  
Qiong Tang ◽  
Jinxiang Dong
Keyword(s):  
Solvent Free ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Brönsted Acid

Synthetic Scope of Brønsted Acid-Catalyzed Reactions of Carbonyl Compounds and Ethyl Diazoacetate

2021 ◽  
Author(s):  
Mizzanoor Rahaman ◽  
M. Shahnawaz Ali ◽  
Khorshada Jahan ◽  
Damon Hinz ◽  
Jawad Bin Belayet ◽  
...  
Keyword(s):  
Carbonyl Compounds ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Ethyl Diazoacetate ◽  
Brönsted Acid ◽  
Acid Catalyzed ◽  
Catalyzed Reactions

scholarly journals Tailoring Lewis/Brønsted acid properties of MOF nodes via hydrothermal and solvothermal synthesis: simple approach with exceptional catalytic implications

2021 ◽  
Author(s):  
Sergio Rojas-Buzo ◽  
Benjamin Bohigues ◽  
Christian W. Lopes ◽  
Débora M. Meira ◽  
Mercedes Boronat ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Active Site ◽  
Solvothermal Synthesis ◽  
Simple Approach ◽  
Organic Reactions ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Acid Properties ◽  
Brönsted Acid

The Brønsted/Lewis acid properties of Hf-MOF-808 can be tuned by simply controlling the solvent employed in its synthesis, with direct catalytic implications on the activity and selectivity of organic reactions sensitive to the active site nature.

Brønsted Acid-Catalyzed Friedel-Crafts-type Alkylation of Arenes with αAryl Diazoacetates

2021 ◽  
pp. 152751
Author(s):  
Wenming Chen ◽  
Guifang Chen ◽  
Biao Wang ◽  
Wei Wang ◽  
Wei Huang ◽  
...  
Keyword(s):  
Bronsted Acid ◽  
Brønsted Acid ◽  
Brönsted Acid ◽  
Acid Catalyzed

scholarly journals Bioinspired Brønsted Acid-Promoted Regioselective Tryptophan Isoprenylations

ACS Omega ◽  
2021 ◽  
Vol 6 (16) ◽  
pp. 10840-10858
Author(s):  
Tushar M. Khopade ◽  
Kalyani Ajayan ◽  
Swapnil S. Joshi ◽  
Amy L. Lane ◽  
Rajesh Viswanathan
Keyword(s):  
Bronsted Acid ◽  
Brønsted Acid ◽  
Brönsted Acid

scholarly journals On the Role of Protonic Acid Sites in Cu Loaded FAU31 Zeolite as a Catalyst for the Catalytic Transformation of Furfural to Furan

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2015
Author(s):  
Łukasz Kuterasiński ◽  
Małgorzata Smoliło-Utrata ◽  
Joanna Kaim ◽  
Wojciech Rojek ◽  
Jerzy Podobiński ◽  
...  
Keyword(s):  
Active Sites ◽  
Acid Sites ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Brønsted Acid Sites ◽  
Protonic Acid ◽  
Brönsted Acid ◽  
Brönsted Acid Sites ◽  
Bronsted Acid Sites

The aim of the present paper is to study the speciation and the role of different active site types (copper species and Brønsted acid sites) in the direct synthesis of furan from furfural catalyzed by copper-exchanged FAU31 zeolite. Four series of samples were prepared by using different conditions of post-synthesis treatment, which exhibit none, one or two types of active sites. The catalysts were characterized by XRD, low-temperature sorption of nitrogen, SEM, H2-TPR, NMR and by means of IR spectroscopy with ammonia and CO sorption as probe molecules to assess the types of active sites. All catalyst underwent catalytic tests. The performed experiments allowed to propose the relation between the kind of active centers (Cu or Brønsted acid sites) and the type of detected products (2-metylfuran and furan) obtained in the studied reaction. It was found that the production of 2-methylfuran (in trace amounts) is determined by the presence of the redox-type centers, while the protonic acid sites are mainly responsible for the furan production and catalytic activity in the whole temperature range. All studied catalysts revealed very high susceptibility to coking due to polymerization of furfural.

Brønsted Acid-Catalyzed Formal (3+3)-Annulation of Propargylic (Aza)-para-Quinone Methides with 4-Hydroxycoumarins and 1,3-Dicarbonyl Compounds

2021 ◽  
Author(s):  
Zong-Wang Qiu ◽  
Xue-Tao Xu ◽  
Han-Peng Pan ◽  
Zhen-Sheng Jia ◽  
Ai-Jun Ma ◽  
...  
Keyword(s):  
Bronsted Acid ◽  
Brønsted Acid ◽  
Quinone Methides ◽  
Dicarbonyl Compounds ◽  
Brönsted Acid ◽  
Acid Catalyzed
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