title: Separation of 1,3-substituted imidazoles for quality control of a Lewis acidic ionic liquid for aluminum electroplating.
abstract: Ionic liquids (ILs) are already used or have great potential in many industrial applications. Knowledge about their unique physicochemical characteristics makes ILs suitable for the electrodeposition of metals with very low negative potentials. Aluminum with its good corrosion protection behavior has great capability to be electroplated from IL electrolytes on steel substrates. The stability of the chosen electrolyte is very important to ensure industrial applicability. In this study, temperature and electrochemical long-term stability from electrolytes based on a Lewis acidic mixture of AlCl3 and 1-ethyl-3-methylimidazolium chloride are investigated. A published method was modified to identify possible degradation products using mass spectrometric detection. The optimized method used an Agilent Zorbax SB-Phenyl column (2.0 × 150 mm, 5 μm particles) with a 20 mmol TFA and 5% ACN mobile phase. This method allowed the quantification of several imidazoles from 0.1 to 100 mg/L. When analyzing the long-term stressed electrolytes, no significant changes in electrolyte composition could be observed.
authors.affiliation: Institute for Chemistry and Technology of Materials, Graz University of Technology, Graz, Austria; CEST Competence Centre for Electrochemical Surface Technology, Wiener Neustadt, Austria.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kosmus
authors.forename: Oliver
authors.initials: O
authors.lastname: Steiner
authors.forename: Walter
authors.initials: W
authors.lastname: Goessler
authors.forename: Bernhard
authors.initials: B
authors.lastname: Gollas
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004595:Electroplating / Q000379:methods*; D007093:Imidazoles / Q000737:chemistry* / Q000302:isolation & purification; D052578:Ionic Liquids / Q000737:chemistry* / Q000302:isolation & purification; D058116:Lewis Acids / Q000737:chemistry* / Q000302:isolation & purification; D013058:Mass Spectrometry
chemical_list: D007093:Imidazoles; D052578:Ionic Liquids; D058116:Lewis Acids; D000535:Aluminum
keywords: Aluminum; Electroplating; HPLC-MS; Imidazoles; Ionic liquids