IR monitoring of absorbent composition and degradation during pilot plant operation

The monitoring of the absorbent during the operation of CO2 separation processes is a necessary and challenging task. The most common absorbent used is an aqueous amine solution. Traditional approaches to analysis such as titration and chromatography are time consuming and only provided limited information. This hinders the ability of process operators to rapidly respond to changes in operating conditions. In this work a combination of infrared (IR) spectroscopy and Principle Component Regression (PCR) have been demonstrated as a rapid and reliable technique to determine the composition of an absorbent during a pilot plant campaign at brown coal power station. The concentration of amine, a degradation product, CO2 and water was monitored throughout the campaign by a method that provided results in minutes. The results were verified by independent sample analysis using acid-base titration, high performance liquid chromatography (HPLC) and 13C NMR spectroscopy. It was necessary to use spectral windowing whe...