Synthesis and characterisation of ionic liquids based on 1-butyl-3-methylimidazolium chloride and MCl(4), M = Hf and Zr.
Dialkylimidazolium chlorometallate molten salts resulting from the combination of zirconium or hafnium tetrachloride and 1-butyl-3-methylimidazolium chloride, [C(1)C(4)Im][Cl], have been prepared with a molar fraction of MCl(4), R = n(MCl4)/n(MCl4) + n([C1C4IM][Cl]) equal to 0, 0.1, 0.2, 0.33, 0.5, 0.67. The structure and composition were studied by Differential Scanning Calorimetry (DSC), (35)Cl (263 to 333 K), (1)H and (13)C solid state and solution NMR spectroscopy, and electrospray ionisation (ESI) mass spectrometry. The primary anions of the MCl(4)-based ILs were [MCl(5)], [MCl(6)] and [M(2)Cl(9)], whose relative abundances varied with R. For R = 0.33, pure solid [C(1)C(4)Im](2)[MCl(6)], for both M = Zr and Hf are formed (m.p. = 366 and 385 K, respectively). For R = 0.67 pure ionic liquids [C(1)C(4)Im][M(2)Cl(9)] for both M = Zr and Hf are formed (T(g) = 224 and 220 K, respectively). The thermal dissociation has been attempted of [C(1)C(4)Im](2)[HfCl(6)], and [C(1)C(4)Im](2)[ZrCl(6)] monitored by (35)Cl and (91)Zr solid NMR (high temperature up to 551 K).
Campbell
Paul S
PS
Université de Lyon, Institut de Chimie de Lyon, UMR 5265 CNRS-Université de Lyon-ESCPE Lyon, LC2P2, Equipe COMS, ESCPE 43 Boulevard du 11 Novembre 1918, 69616, Villeurbanne, France.
Santini
Catherine C
CC
Bouchu
Denis
D
Fenet
Bernard
B
Rycerz
Leszek
L
Chauvin
Yves
Y
Gaune-Escard
Marcelle
M
Bessada
Catherine
C
Rollet
Anne-Laure
AL