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New article in ChemPhysChem

Ionic Fluids Containing Both Strongly and Weakly Interacting Ions of the Same Charge Have Unique Ionic and Chemical Environments as a Function of Ion Concentration

H. Wang, S. P. Kelley, J. W. Brantley III, G. Chatel, J. Shamshina, J. F. B. Pereira, V. Debbeti, A. S. Myerson, R. D. Rogers

Abstract

Liquid multi-ion systems made by combining two or more salts can exhibit charge ordering and interactions not found in the parent salts, leading to new sets of properties. This is investigated herein by examining a liquid comprised of a single cation, 1-ethyl-3-methylimidazolium ([C2mim]+), and two anions with different properties, acetate ([OAc]) and bis(trifluoromethylsulfonyl)imide ([NTf2]). NMR and IR spectroscopy indicate that the electrostatic interactions are quite different from those in either [C2mim][OAc] or [C2mim][NTf2]. This is attributed to the ability of [OAc] to form complexes with the [C2mim]+ ions at greater than 1:1 stoichiometries by drawing [C2mim]+ions away from the less basic [NTf2] ions. Solubility studies with molecular solvents (ethyl acetate, water) and pharmaceuticals (ibuprofen, diphenhydramine) show nonlinear trends as a function of ion content, which suggests that solubility can be tuned through changes in the ionic compositions.

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Available on the website of ChemPhysChem

Inside Cover IN ChemCatChem

Our last article selected as Inside Cover in ChemCatChem journal

cover ChemCatChem Dec 2014

The inside cover picture shows how the eco-friendly combination of an iron salt as catalyst, aqueous hydrogen peroxide as oxidant, and ultrasound as activation method leads to the selective oxidation of d-glucose into gluconic acid. Indeed, gluconic acid is an attractive target for industry, essentially produced through biotechnological processes. D. Rinsant, G. Chatel, and F. Jérôme demonstrated a sono-Fenton effect and estimated the production of HO⋅ radicals involved in the oxidation reaction. This work is an example of great opportunities that the sonochemical activation can offer in catalysis, involving eco-efficient processes. The article highlighted by this cover can be found on page 3355 (here) of Issue 12, 2014.

More information here.

Our article on ChemCatChem

Efficient and Selective Oxidation of D-Glucose into Gluconic acid under Low-Frequency Ultrasonic Irradiation

Damien Rinsant, Gregory Chatel*and François Jérôme

Abstract

The production of gluconic acid from d-glucose represents an attractive target for industry. In this work, we propose an efficient, eco-friendly, and selective method to oxidize d-glucose with aqueous H2O2 in the presence of FeSO4 as a catalyst. The reaction was improved significantly under ultrasonic (US) activation, which led to excellent yields in only a few minutes. In addition, we determined that the reaction occurred through a sono-Fenton process by studying the production of hydroxyl radicals and optimizing the experimental conditions of the reaction. The energy consumption of the process was also investigated in this study.

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Available on the website of ChemCatChem

Congratulations to Damien for this work performed during his 2014 internship!

 

Our review in Chem. Soc. Rev.

Chem. Soc. Rev., 2014,  Advance Article, DOI: 10.1039/C4CS00193A

Abstract:

Ionic liquids, as reaction media, and sonochemistry are two recently developing fields of chemistry that present some similarities. Firstly, they constitute separately unconventional approaches to reaction chemistry that, in many cases, generate improvements in yield, rate and selectivity compared to classical chemistry, or even change the mechanisms or products expected. In addition, both are often associated with green chemistry concepts as a result of their properties and their possible eco-friendly uses. A recent trend has been to combine these two technologies in a range of different applications and the results demonstrate very significant and occasionally surprising synergetic effects. Here we critically review the advantages and limitations of the ionic liquid/ultrasound combination in different applications in chemistry, to understand how, and in which respects, it could become an essential tool of sustainable chemistry in the future. Many practical and theoretical aspects associated with this combination of techniques are not understood or resolved and we discus where fundamental studies might further advance this field.

Great collaboration on this article with Doug MacFarlane, from Monash University (Australia)!