Effect of ionic liquids on dissociation of copper flake into copper nanoparticles and its application to facilitated olefin transport membranes

• Published in: Journal of membrane science Vol. 374; no. 1; pp. 43 - 48
• Main Authors: Han, Kook In, Kang, Sang Wook, Kim, Jongho, Kang, Yong Soo
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.05.2011; Elsevier
• Subjects: artificial membranes; Chemistry; Colloidal state and disperse state; copper; Copper nanoparticle; dissociation; energy; Exact sciences and technology; General and physical chemistry; Interaction; Ionic liquid; ionic liquids; Membranes; nanoparticles; olefin; Olefin and facilitated transport; Physical and chemical studies. Granulometry. Electrokinetic phenomena; spectroscopy; transmission electron microscopy; Copper nanoparticle; Interaction; Olefin and facilitated transport; Ionic liquid; Surface charge; Separation; Nanoparticle; Transition metal; Paraffin; Composite material; Liquid metal; Transmission electron microscopy; Olefin; Synthesis; Binding energy; Distribution; Membrane; Micrometer; Raman spectrometry; Dissociation; Copper; Transport; Ethylenic compound
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2011.03.005

► Copper nanoparticles dis-agglomerated by ionic liquid. ► Reversible interaction between surface of copper nanoparticles and olefin. ► Facilitated olefin transport membrane utilizing copper nanoparticles as olefin carrier. Effects of ionic liquids on dissociation of micrometer-sized copper flakes into copper nanoparticles and on facilitated olefin transport were investigated. Three different ionic liquids (ILs) of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM +BF 4 −), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM +PF 6 −) and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM +BF 4 −) were employed for facile synthesis of copper nanoparticles and for inducing the partial surface positive charge of the copper nanoparticles for facilitated olefin transport. The positively charged surface was induced by interactions with anion of the ILs as evidenced by FT-Raman spectroscopy. The intensity of the interactions depending upon the ionic liquid resulted in the difference in the size and its distribution of the nanoparticles as confirmed by TEM images and UV–vis spectra. The separation performance of the ionic liquid/Cu metal composite membranes for olefin/paraffin mixtures was in the following order: EMIM +BF 4 −/Cu < BMIM +PF 6 −/Cu < BMIM +BF 4 −/Cu. Surprisingly, the binding energies of the copper atoms in the ionic liquid/Cu metal composites were strongly correlated the separation performance. Consequently, it was concluded that facilitated olefin transport was consistent with the trend of increasing binding energy of copper atoms.