218f Rules to Select Solvents for Scrubbing CO2 from Fossil Power Stations

Wolfgang Arlt and Liudmila Mokrushina. Chair of Separation Science and Technology, University of Erlangen, Egerlandstr. 3, Erlangen, Germany

The present amine-based technology scrubbs CO2 from flue gas by a chemical equilibrium reaction. Some disadvantages are obvious:

1. the recovery of the CO2-rich solution requires so much energy that the electrical output is reduced by 25-35 %

2. Amines are harmful to the environment and should be removed from the flue gas

3. Some amines form irreversible products

The focus of this lecture is to show how a thermodynamical analysis will lead to more economical solvents.

It turns out that the following properties are advantageous:

1. “no” vapour pressure

2. molecular weight around some few thousand Dalton

3. low viscosity