Low Toxic Corrosion Inhibitors for Amine-based CO2 Capture Process

This work evaluated inhibition performance of a low toxic corrosion inhibitor, namely sodium thiosulfate, on carbon steel in 5.0 kmol/m(3) monoethanolamine (MEA) solution at 80 degrees C and 0.55 mol/mol CO2 loading. Effects of corrosion inhibitor concentration and process contaminants, including formate and chloride, on inhibition performance were studied. The results show that sodium thiosulfate significantly reduced corrosion rate with an inhibition efficiency of up to 94% in short term exposure tests, but did not perform well in long term exposure tests due to the instability of passive film. Its inhibition efficiency was not affected by the presence of chloride and formate. (C) 2013 The Authors. Published by Elsevier Ltd. Open access under CC BY-NC-ND license. Selection and/or peer-review under responsibility of GHGT