Regular Article

Kinetics study and simulation of CO₂ absorption into mixed aqueous solutions of methyldiethanolamine and hexylamine

¹ Ecole Nationale Polytechnique, Laboratoire de valorisation des énergies fossiles, El Harrach, Algerie
² MINES ParisTech, PSL Research University, CES -Centre d'efficacité énergétique des systèmes- 60, Boulevard Saint Michel, Paris, France

^* Corresponding author: e-mail: ammar.mehassouel@g.enp.edu.dz

Received: 27 October 2017
Accepted: 23 April 2018

Abstract

This study investigated kinetics of CO₂ absorption into mixed methyldiethanolamine (MDEA) and hexylamine (HA) solutions in a Lewis cell reactor. The experiments were conducted in the temperatures 298, 313 and 333 K with mass concentrations MDEA 37 wt.% + HA 3 wt.%, MDEA 35 wt.% + HA 5 wt.% and MDEA 33 wt.% + HA 7 wt.%. Our results showed that adding a small amount of hexylamine enhances the kinetics of CO₂ absorption and that the kinetics of CO₂ absorption with aqueous MDEA 37 wt.% + HA 3 wt.% is pseudo first order regime with reduced activation energy compared to that of MDEA 40 wt.%. The absorption/regeneration system was simulated using Aspen plus™ software for the treatment of gas streams from cement plant in a post-combustion process. The analysis of our results established that blended solvent MDEA 37 wt.% + HA 3 wt.% gives lower energy consumption than that of MDEA 40 wt.%.