(174cf) Reaction Kinetics of Carbon Dioxide with Aqueous Solution of DEEP Eutectic Solvent & Methyl Diethanolamine Amine Using the Stopped Flow Technique

REACTION KINETICS OF CARBON
DIOXIDE WITH AQUEOUS SOLUTION OF DEEP EUTECTIC SOLVENT & METHYL
DIETHANOLAMINE AMINE USING THE STOPPED FLOW TECHNIQUE

H.
Ababneh, A. Benamor, Mustafa Nasser and M. H. El-Naas

Gas
processing Centre, College of Engineering Qatar University, P.O 2713, Doha,
Qatar

hababneh@qu.edu.qa, Benamor.abdelbaki@qu.edu.qa

Global warming has become a worldwide issue
lately. Greenhouse gas emissions, which are responsible of the observed
temperature increase, have reached alarming levels leading the governments and
agencies around the world to force stringent and strict regulations on the
greenhouse gases emissions. Among the most established technologies to capture
CO₂ is amine-based scrubbing. However, amine scrubbing, in addition
of being an energy-intensive process has other operational issues. The
usage of Deep Eutectic
Solvents (DES) as rate promoters in the CO₂ amine absorption process
have not taken much consideration from the research community as the CO₂
reaction with mixtures of DES and MDEA has not been studied yet.  In this work, for the first time, the
kinetics data of CO₂ reaction with DES and MDEA using stopped-flow
method is presented. The DES consisted of equimolar amounts of lactic acid,
β-alanine, and water. The temperature changed from 298 to 313 K for a MDEA
solution concentration varying from 0.1 to 1 molar, while DES concentration
ranged from 0.1 to 1% of the total mass of the solution. The overall
rate constants (Figure 1) increased with increasing temperature and with
increasing DES concentration within the solution. The obtained results from
this work showed that DES could be good rate promoters for the actual
amine-based CO₂ capture technology and another step in the ongoing
efforts for the development of efficient new solvents for the removal of CO₂
from flue and industrial gases.

Keywords: CO₂
Capture, Methyldiethanolamine, Deep Eutectic Solvent, Kinetics, Stopped Flow

Figure 1: Overall rate constant for CO₂-DES-MDEA
reaction at different concentations