Assessment of the volatility of amine degradation compounds in aqueous MEA and blend of 1-(2HE)PRLD and 3A1P

Abstract

Amine-based carbon capture has proven to be a mature technology, but challenges remain. Emission control of potentially hazardous compounds is critical to ensure the long-term viability of the technology. The ability to predict which compounds to expect in gas emissions and at what levels is fundamental. This work aims to provide a qualitative and quantitative assessment of the volatility of both MEA and HS3 blend degradation products. VLE experiments were performed with different degraded solutions over a temperature range from 40 to 100 °C. Samples were analyzed using extensive LC-MS methods to quantify over 40 degradation compounds. Henry's constants were calculated to assess their volatility. The compiled results allow the ranking of most of the compounds studied in terms of volatility, and the quantification of their relative volatility compared to each other. Pyrazines and alkylamines are among the most volatile, followed by aldehydes, ketones, nitrosamines, and finally, larger amides. When compared, the volatilities of the degradation compounds are consistent from one degraded solution to another, highlighting the possibility of generalization from one solvent to another. This consistency is also observed with the dilute version of the degraded solutions simulating water-wash conditions. Finally, this work provides insight into the temperature dependence of the volatilities of the compounds studied. The methodology used provides a valuable and new type of data that have never been published before on the volatility of amine degradation compounds. The results can be used to better understand emissions and the design of emission control technologies.