ao6b00104_si_001.pdf (295.89 kB)
Adventitious Water Sorption in a Hydrophilic and a Hydrophobic Ionic Liquid: Analysis and Implications
journal contribution
posted on 2016-09-16, 12:36 authored by Radhika
S. Anaredy, Anthony J. Lucio, Scott K. ShawThe sorption of water
in ionic liquids (ILs) is nearly impossible
to prevent, and its presence is known to have a significant effect
on the resulting mixtures’ bulk and interfacial properties.
The so-called “saturation” water concentrations have
been reported, but water sorption rates and mixing behaviors in ILs
are often overlooked as variables that can significantly change the
resulting mixtures’ physical properties over experimental time
frames of several minutes to hours. The purpose of this work is to
establish a range of these effects over similar time frames for two
model ILs, protic ethylammonium nitrate (EAN) and aprotic butyltrimethylammonium
bis(trifluoromethylsulfonyl)imide (N1114 TFSI), as they are exposed
to controlled dry and humid environments. We report the water sorption
rates for these liquids (270 ± 30 ppm/min for EAN and 30 ±
3 ppm/min for N1114 TFSI), examine the accuracy and precision associated
with common methods for reporting water content, and discuss implications
of changing water concentrations on experimental data and results.