Degradation of Amine Solvents Used for Co2 Removal from Flue Gas with High Co₂ Concentration

Abstract

In the ethanolamine (MEA) solution, during the absorption and desorption of CO2 undesired compounds are produced as a result of degradation of an amine. Degradation not only reduces the absorption capacity of the solution but also leads to many operational problems. Furthermore, measuring of the degradation products is of great importance in terms of environmental issues. For the determination of MEA degradation products, mainly chromatographic techniques are used, sometimes coupled with other instrumental methods, e.g. GC-MS. As a part of this work, research was conducted to identify MEA thermal and oxidative degradation products and to develop a method for quantitative analysis of the main thermal degradation products such as OZD, HEIA and HEEDA and oxidative degradation products: HEA and HEI. Samples drawn from a test bench for CO2 capture from synthetic flue gas with an increased content of carbon dioxide were tested. As a research result, a method for the quantitative determination of the main degradation products was developed, the concentrations of degradation products and the rate of their formation were determined, which allows to qualify the solution shelf life.

Hybrid Smart Strategies to Predict Amine Thermal Degradation in Industrial CO2 Capture Processes

“…CO 2 loading stimulates thermal degradation, and a larger loading of CO 2 was proven to increase thermal degradation either by increasing the proton donor availability through catalyzing the dehydration or through the formation of more carbamate . Regarding the impact of time, thermal degradation products usually increase with time . Obviously, the concentration of the solvent in the system plays a significant role in the thermal degradation of the solvent.…”

“… 31 Regarding the impact of time, thermal degradation products usually increase with time. 10 Obviously, the concentration of the solvent in the system plays a significant role in the thermal degradation of the solvent. For instance, increasing MEA concentration unexpectedly decreases the rate of thermal degradation.…”

“…Quantification of the products of the oxidative and thermal degradation of MEA verified that differences in the type of degradation products between samples of lean and rich amine indicate the chemical reaction of the products. Rich amine was more susceptible to thermal degradation than oxidative degradation . Operation time plays a major role in the solvent degradation.…”

“…Rich amine was more susceptible to thermal degradation than oxidative degradation. 10 Operation time plays a major role in the solvent degradation. MEA concentration decreases by 95% due to the thermal degradation at 160 °C for 8 weeks; however, the remaining solvent maintains its capacity at 22% to remove CO 2 , possibly owing to the capacity of some of the degradation product to remove CO 2 .…”