Application of Ionic Liquids in Oxidative and Acidic Catalysis Nina Kuznetsova1; Nikolay Adonin1; Bair Bal'zhinimaev1; 1BORESKOV INSTITUTE OF CATALYSIS, Novosibirsk, Russian Federation; PAPER: 165/Molten/Regular (Oral) SCHEDULED: 11:20/Tue./Bossa (150/3rd) ABSTRACT: Ionic liquids (IL) are drawing increasing and considerable attention in the field of catalysis as perfect, non-volatile, thermally stable solvents and media for liquid phase selective reactions [1]. We represent here examples from the catalytic chemistry, where ILs has been successfully used for improving two industrially important reactions. Well-known commercial synthesis of terephthalic acid (TPA) is based on aerobic oxidation of p-xylene in acetic acid solution of the Co/Mn/Br catalyst, that followed by the cost and energy-consuming hydropurification of the crude TPA product from p-carboxybenzaldehyde (4-CBA) [2]. We showed that addition of ILs (dialkylimidazolium acetate and bromide) and ammonium acetate changes properties of the conventional solvent to improve solubility and accelerate oxidation of 4-CBA to TPA. Efficient combinations of the additives and appropriate reaction conditions have been selected to obtain the target product with 4-CBA content below 25 ppm [3]. Positive effect is caused by excellent solvating ability of ILs for TPA and 4-CBA. The designed catalytic systems can be applied to obtain high-quality TPA just after oxidation stage, without the hydropurification. The next example is related to the alkylation of benzene with dodecene-1 for production of linear alkylbenzene catalyzed with binary 1-butyl-3-methylimidazolium chloride-aluminum chloride system. This catalyst showed high performance in the synthetic detergent not only from neat dodecene-1, but from the feedstock containing a mixture of C10-C13 alkanes and C10-C13 alkenes. The best results have been obtained when the mole fraction of [BMIM]Cl ionic liquid is around 40%. Furthermore, the optimal reaction conditions, such as benzene/alkene ratio (1.6-3) and temperature (30-40°C), have been found. In this case, a very high 98-99% yield of detergent is achieved [4]. References: [1] C. Dai, J. Zhang, C. Huang and Z. Lei, Chem. Rev. 117 (2017) 6929-6983. [2] C. Park, J. R. Sheehan, In Kirk-Othemer Encyclopedia of Chemical Technology, 4th Ed. V.18, New York, 1996, pp. 478-491. [3] N. I. Kuznetsova, B. S. Bal'zhinimaev, A. Bhattacharyya, J. T. Walenga, ChemistrySelect, 2 (2017) 11815-11820. [4] M.G. Riley, A. Bhattacharyya, N.Y. Adonin, M.N. Timofeeva, S.A. Prikhodko, B.S. Bal'zhinimaev, Benzene alkylation using acidic ionic liquids. US Patent 9328037. |