DISPROPORTIONATION OF POLYNUCLEAR CHLOROETHYLALUMINATE ANIONS IN ACIDIC 1-BUTYL-3-METHYLIMIDAZOLIUM CHLORIDE-ALETCL(2) MOLTEN-SALTS IN THE PRESENCE OF A HYDROCARBON PHASE

Various 1-butyl-3-methylimidazolium chloride-AlEtCl(2) molten salt mix tures have been equilibrated in the presence of cyclopentane, and the resulting products monitored by Raman spectroscopy in the hydrocarbon and molten salt phases. The experiments were conducted either statical ly by equilibration of a given volume of cyclopentane with an equal vo lume of molten salt or dynamically by using a continuous-extraction ap paratus. The results show for the first time that polynuclear anions d isproportionate and/or dissociate. When a full extraction is performed from a melt based on AlEtCl(2) with any mole fraction higher than 0.6 67 the resulting molten phase is comprised of [AlCl4](-). The nature o f the extracted alkylaluminium chloride compound depends on the initia l composition. For a melt containing an AlEtCl(2) mole fraction of 0.5 -0.75 a mixture of AlEt(2)Cl and Al(2)Et(3)Cl(3) is extracted by the h ydrocarbon phase. When this mole fraction is 0.75 the only product ext racted is Al(2)Et(3)Cl(3). The compound AlEtCl(2) is extracted from a mixed acidic salt based on AlCl3 and AlEtCl(2).