Determination of Water in 1-Ethyl-3-methylimidazolium tetrafluoroborate

Graham T. Cheek, William O'Grady, Steven Lawrence
2007 ECS Transactions   unpublished
Determination of water in 1-ethyl-3-methylimidazolium tetrafluoroborate has been carried out using both electrochemical and infrared spectroscopic methods. At platinum electrodes, voltammetric responses for water oxidation and reduction have been used to prepare calibration curves. It has been found that the water oxidation current at +2.4V vs Ag/AgCl is suitable for water determination to at least 40 mM. Infrared spectroscopy of water in quartz cells in the OH stretching region revealed an IR
more » ... eature at 3550 cm -1 for water additions to 20 mM, with another feature at 3650 cm -1 appearing at higher water concentrations. For the lowfrequency feature, a calibration curve is linear to 14 mM. Both electrochemical and IR methods provide a lower limit of detection of approximately 1 mM water in this ionic liquid.
doi:10.1149/1.2408973 fatcat:vfnk5dzhgngqfk4xwj6nsjfury