Minimizing solvent degradation and corrosion using multifunctional additive

Abstract

Solvent degradation and metal corrosion are critical concerns of a post-combustion CO 2 capture process. Systemic analysis indicated that oxidation, nitrosation, and corrosion reactions occur or initiatethrough a radical reaction and thus addition of a radical scavenger is expected to work effectively to avoid these reactions. Here, for the first time, a multifunctional organic compound (CAER additive) has been evaluated as an inhibitor. The corrosion rate of A106 in 5 mol/kg MEA was lowered by one order of magnitude when 5mM inhibitor was added. Oxidation of 5 mol/kg MEA was monitored based on accumulation of formate concentration in the solution and formate levels were below the detection limit when CAER additive was present. Furthermore, the same additive was found to inhibit nitrosation of 5 mol/kgmorpholine with 100 ppm of NO 2 gas by 91% in 6 h.

Influence of Dissolved Metals on N-Nitrosamine Formation under Amine-based CO2 Capture Conditions

“…EDTA effectively suppressed the Cu effect. Development of alternative oxidation inhibitors for amine solvents should evaluate the extent to which they can mitigate Cu catalysis for N -nitrosamine formation . Lastly, the use of tap water or surface waters to constitute solvents or washwaters may be a concern given that Cu promoted nitrosamine formation from primary amines at concentrations lower than the Maximum Contaminant Level permitted in drinking water.…”

Important Aspects Regarding the Chemical Stability of Aqueous Amine Solvents for CO2 Capture

“…This includes instrumentation for both gas and liquid chromatography (GC and LC, respectively), often coupled with mass spectrometry (MS) or other detectors. Common variations of GC and LC are GC−MS, ,,,,− GC coupled with nitrogen chemoluminescence detection (GC-NCD) , or flame ionization detection (GC-FID), LC with tandem mass spectrometry (LC–MS/MS), ,,,,, high-performance LC (HPLC) ,,,,, and HPLC coupled with time-of-flight MS detection (HPLC TOF-MS). ,, Other important analytical methods include ion chromatography (IC), ,,,,,,,,,,,, capillary electrophoresis (CE), , nuclear magnetic resonance (NMR), ,,,, and Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR–MS). , A combination of several of these is required for analyzing all degradation compounds; GC-NCD is often used specifically for the analyses of total nitrosamines, while IC is often used for carboxylic acids or other anionic compounds or the amine itself. GC–MS and LC–MS/MS, HPLC techniques are used for various degradation compounds.…”

“…Common variations of GC and LC are GC−MS, 12,15,29,46,108−112 GC coupled with nitrogen chemoluminescence detection (GC-NCD) 56,104 or flame ionization detection (GC-FID), 113 LC with tandem mass spectrometry (LC−MS/MS), 27,29,46,54,56,109 high-performance LC (HPLC) 22,23,26,66,114,115 and HPLC coupled with time-offlight MS detection (HPLC TOF-MS). 66,108,116 Other important analytical methods include ion chromatography (IC), 15,22,23,26,27,46,54,66,108,109,111,115,116 capillary electrophores i s ( C E ) , 1 1 4 , 1 1 7 n u c l e a r m a g n e t i c r e s o n a n c e (NMR), 15,22,109,110,118 and Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR−MS). 1,109 A combination of several of these is required for analyzing all degradation compounds; GC-NCD is often used specifically for the analyses of total nitrosamines, while IC is often used for carboxylic acids or other anionic compounds or the amine itself.…”