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Generation of superoxide ion in pyridinium, morpholinium, ammonium, and sulfonium - based ionic liquids and the application in the destruction of toxic chlorinated phenols / Maan Hayyan in Industrial & engineering chemistry research, Vol. 51 N° 32 (Août 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10546-10556 Titre : Generation of superoxide ion in pyridinium, morpholinium, ammonium, and sulfonium - based ionic liquids and the application in the destruction of toxic chlorinated phenols Type de document : texte imprimé Auteurs : Maan Hayyan, Auteur ; Farouq S. Mjalli, Auteur ; Mohd Ali Hashim, Auteur Année de publication : 2012 Article en page(s) : pp. 10546-10556 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Ionic  liquid Résumé : Generation of superoxide ion (O2•―) was carried out in four ionic liquids (ILs) having the same anion, bis(trifluoromethylsulfonyl)imide [N(Tf)2]―, and different cations, N-hexylpyridinium [HPy]+, N-methoxyethyl-N-methyl-morpholinium [MO1,1O2]+, N-ethyl-N,N-dimethyl-2-methoxyethylammonium [N112,1O2]+, and triethylsulfonium [S222]+. Cyclic voltammetry (CV) and chronoamperometry (CA) electrochemical techniques were used in this investigation. It was found that O2•― is not stable in the [HPy]+-based IL. On the other hand, CV showed that the electrochemically generated O2•― is stable in [MO1,1O2]+-, [N112,1O2]+-, and [S222]+-based ILs for the time duration of the experiment. The long-term stability of the generated O2•― was then investigated by dissolving potassium superoxide (KO2) in dimethyl sulfoxide (DMSO) in the presence of the corresponding IL. It was found that ILs containing [MO1,1O2]+ and [N112,1O2]+ offer a promising long-term stability of O2•― for various reactions to be used for several applications. However, it was found that after 2 h, about 92.5% of the generated O2•― in [S222]+ based IL was consumed. The diffusion coefficient and solubility of O2 in the studied ILs were then determined using CV and CA techniques simultaneously. It was found that diffusion coefficients and CA steady-state currents increase with temperature increases, while the solubility of O2 decreased. To our best knowledge, this is the first time that morpholinium and sulfoniumbased ILs were utilized as media for chemical and electrochemical generation of O2•―. Additionally, the chemically generated O2•―, by dissolving KO2, was then used for the destruction of 2,4-dichlorophenol (DCP) in [MO1,1O2][N(Tf)2] under ambient conditions. The destruction percentage was higher than 98%. This work represents a novel application of the chemically generated O2•― for the destruction of toxic chlorinated phenols in ILs media. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26259758 [article] Generation of superoxide ion in pyridinium, morpholinium, ammonium, and sulfonium - based ionic liquids and the application in the destruction of toxic chlorinated phenols [texte imprimé] / Maan Hayyan, Auteur ; Farouq S. Mjalli, Auteur ; Mohd Ali Hashim, Auteur . - 2012 . - pp. 10546-10556. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 32 (Août 2012) . - pp. 10546-10556 Mots-clés : Ionic  liquid Résumé : Generation of superoxide ion (O2•―) was carried out in four ionic liquids (ILs) having the same anion, bis(trifluoromethylsulfonyl)imide [N(Tf)2]―, and different cations, N-hexylpyridinium [HPy]+, N-methoxyethyl-N-methyl-morpholinium [MO1,1O2]+, N-ethyl-N,N-dimethyl-2-methoxyethylammonium [N112,1O2]+, and triethylsulfonium [S222]+. Cyclic voltammetry (CV) and chronoamperometry (CA) electrochemical techniques were used in this investigation. It was found that O2•― is not stable in the [HPy]+-based IL. On the other hand, CV showed that the electrochemically generated O2•― is stable in [MO1,1O2]+-, [N112,1O2]+-, and [S222]+-based ILs for the time duration of the experiment. The long-term stability of the generated O2•― was then investigated by dissolving potassium superoxide (KO2) in dimethyl sulfoxide (DMSO) in the presence of the corresponding IL. It was found that ILs containing [MO1,1O2]+ and [N112,1O2]+ offer a promising long-term stability of O2•― for various reactions to be used for several applications. However, it was found that after 2 h, about 92.5% of the generated O2•― in [S222]+ based IL was consumed. The diffusion coefficient and solubility of O2 in the studied ILs were then determined using CV and CA techniques simultaneously. It was found that diffusion coefficients and CA steady-state currents increase with temperature increases, while the solubility of O2 decreased. To our best knowledge, this is the first time that morpholinium and sulfoniumbased ILs were utilized as media for chemical and electrochemical generation of O2•―. Additionally, the chemically generated O2•―, by dissolving KO2, was then used for the destruction of 2,4-dichlorophenol (DCP) in [MO1,1O2][N(Tf)2] under ambient conditions. The destruction percentage was higher than 98%. This work represents a novel application of the chemically generated O2•― for the destruction of toxic chlorinated phenols in ILs media. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26259758