Effects of shape, porosity, and operating parameters on carbon dioxide recovery in polytetrafluoroethylene membranes.

In this study, the recovery of carbon dioxide using an absorbent composed of 2-amino-2-methyl-l-propanol (AMP)+monoethanolamine (MEA)+piperazine (PZ) in polytetrafluoroethylene (PTFE) membrane contactors was investigated. Experiments were conducted using various gas flow rates, liquid flow rates, absorbent blends, and pore size membranes. CO(2) recovery increased with increasing liquid flow rates. The blended amine absorbent had a synergistic effect on CO(2) recovery. CO(2) recovery increased as the pore size of the PTFE membrane decreased. An asymmetric membrane had a better CO(2) recovery than that of symmetric membrane. Besides, membrane mass transfer coefficient and operational stability of asymmetric membrane were enhanced. For an asymmetric membrane, the smaller pore-size side of the membrane surface contacting the liquid phase can reduce the level of wetting of the membrane.