Evaluation of CO2 absorption characteristics of low-cost Al2O3/MeOH nanoabsorbent using porous Nickel foam for high efficiency CO2 absorption system

This study proposes an effective strategy to enhance the capturing of CO2 using the Al2O3 nanoparticle-enhanced methanol absorbents with the porous metal foam, which requires no additional energy or operating cost. To investigate CO2 absorption performance, the viscosity and surface tension of Al2O3/MeOH nanoabsorbent under various conditions were measured. Moreover, the behavior of the CO2 bubble and absorption processes was analyzed. As a result, a CO2 mole fraction in the absorbents increased up to 379% when operating pressure increased to 1 MPa and it also increased up to 488% when a concentration of 0.1 wt% Al2O3 nanoparticles was added to the MeOH absorbent. Besides, when 0.1 wt% Al2O3/MeOH nanoabsorbent and porous Ni foam were used, CO2 absorption increased up to 503% compared to pure MeOH without the porous Ni foam. It was concluded that a hybrid system using Al2O3 nanoparticles and porous Ni foam significantly enhanced CO2 absorption due to the hydrodynamic and forced bubble-breaking mechanisms. [Display omitted] •CO2 absorption enhancement of Al2O3 nanoabsorbent with porous foam was investigated.•Al2O3 nanoparticles improved thermophysical properties of MeOH absorbent.•Maximum enhancement of 503% was obtained using Al2O3 nanoabsorbent with porous foam.•Porous foam elevated the bubble breaking effect during CO2 absorption.