title: Alkaline ionic liquids applied in supported ionic liquid catalyst for selective hydrogenation of citral to citronellal.
abstract: The challenge in preparation of ionic liquids containing a strong alkaline anion is to identify a suitable cation which can tolerate the harsh conditions induced by the anion. In this study, a commercial quaternary ammonium compound (quat) benzalkonium [ADBA] (alkyldimethylbenzylammonium) was used as a cation in the synthesis of different alkaline ionic liquids. In fact, the precursor, benzalkonium chloride, is a mixture of alkyldimethylbenzylammonium chlorides of various alkyl chain lengths and is commonly used in the formulation of various antiseptic products. The prepared ionic liquids were utilized as Supported Ionic Liquid Catalysts (SILCAs). Typically, a SILCA contains metal nanoparticles, enzymes, or metal complexes in an ionic liquid layer which is immobilized on a solid carrier material such as an active carbon cloth (ACC). The catalysts were applied in the selective hydrogenation of citral to citronellal which is an important perfumery chemical. Interestingly, 70% molar yield toward citronellal was achieved over a catalyst containing the alkaline ionic liquid benzalkonium methoxide.
authors.affiliation: Laboratory of Industrial Chemistry and Reaction Engineering, Process Chemistry Centre, Åbo Akademi University Åbo-Turku, Finland.
authors.forename: Eero
authors.initials: E
authors.lastname: Salminen
authors.affiliation: Laboratory of Industrial Chemistry and Reaction Engineering, Process Chemistry Centre, Åbo Akademi University Åbo-Turku, Finland.
authors.forename: Pasi
authors.initials: P
authors.lastname: Virtanen
authors.affiliation: Laboratory of Industrial Chemistry and Reaction Engineering, Process Chemistry Centre, Åbo Akademi University Åbo-Turku, Finland ; Laboratory of Technical Chemistry, Department of Chemistry, Chemical-Biological Centre, Umeå University Umeå, Sweden.
authors.forename: Jyri-Pekka
authors.initials: JP
authors.lastname: Mikkola
keywords: catalysis; fine chemicals; hydrogenation; ionic liquids; supported ionic liquid catalysts