CO₂ absorption in membrane contactor using piperazine, monoethanolamine and diethanolamine: A mass transfer and performance study

Carbone dioxide has been demonstrated to be the largest component of greenhouse gases, which increases the temperature of the earth's surface. Therefore, much effort has been endeavor to recover CO₂. Recently, polymeric micro-porous membrane contactors have been proposed as an alternative technology for the conventional gas absorption equipments such as bubble column, packed tower and sieve trays column. In this work, three concentrations of aqueous piperazine (PZ) solutions namely 0.2 M, 0.6 M and 1 M in contact with polyvinylidene fluoride (PVDF) capillary membrane. Moreover, the absorption performances were compared with the aqueous solution of 1M monoethanolamine (MEA) and 1 M diethanolamine (DEA). The results revealed that the efficiency of amine solutions in CO₂ absorption were according to the order of 1 M PZ > 1 M MEA > 0.6 M PZ > 1 M DEA > 0.2 M PZ. It was found that the efficiency of the system was controlled by the liquid phase resistance which could be improved with the increased of the liquid flow rate.