Activated MDEA is commonly used for CO2 removal in gas treatment plants and as a tertiary amine it is generally regarded as being of lower corrosivity than the secondary and primary alkanolamines. This lower corrosivity allows the use of carbon steel. The need to reduce CO2 emissions has led to the development of amino acid based solvents having greater stability in the presence of oxygen a traditional weakness of alkanolamines. There is limited literature available to guide alloy selection for these newer solvents. This paper will describe two failure case histories showing the limitations of carbon steel. The first example describes the failure of carbon steel tubes exposed to lean MDEA in an amine stripper reboiler. The point of failure was where the reboiler tube passed through the reboiler baffle plate. The second example records the high corrosion rates and locations of major damage suffered by carbon steel in a plant capturing CO2 from boiler flue gas and utilizing an amino acid based solvent.