Recently, aqueous mixtures of alkanolamines and ionic liquids had emerged as potential solvents for CO2 capture. Solubility data of CO2 in aqueous mixtures of monoethanolamine (MEA) and 1-n-butyl-3-methylimidazolium tetrafluoroborate ([bmim] [BF4]) are already available in the literature. However, data on the corrosiveness of these new solvents with regards to carbon steel are still scarce. In this work, carbon steel corrosion behavior in carbonated aqueous mixtures of MEA and [bmim] [BF4] was investigated using potentiodynamic polarization and weight loss methods at fixed CO2 loading of 0.55 mol/mol. The corrosion rates were measured for [bmim] [BF4] concentration ranging from 0.1 to 1.0 M and at temperatures of 40 and 80 degrees C. Carbon steel corrosion rates obtained from the two methods are in agreement; and showed that the presence of [bmim] [BF4] in the carbonated solution has reduced the solution corrosivity to carbon steel for carbonated 4.0 M MEA/[bmim] [BF4] system, but increased that of carbonated 2.0 M MEA/[bmim][BF4] system. Scanning electron microscopy (SEM) images demonstrated that immersed specimens were severely corroded in carbonated 2.0 M MEA/[bmim] [BF4] system. While for carbonated 4.0 M MEA/[bmim] [BF4] system, a protective surface layer was formed as [bmim] [BF4] concentration and temperature increased, respectively.
- co2 absorption,
- corrosion rate,
- potentio-dynamic polarization,
- mea/ [bmim] [bf4],
- temperature ionic liquids,
Available at: http://works.bepress.com/rozita_yusoff/3/