CO2 absorption intensification using novel DEAB amine-based nanofluids of CNT and SiO2 in membrane contactor

Abstract

Recent developments in nanotechnology have a great impact to improve the mass transfer in gas-liquid systems. The effect of nanoparticles was taken into account considering Grazing effect and Brownian motion as main phenomena of mass transfer enhancement in nanofluids. In the present study, a sensitivity analysis was performed to evaluate the influence of nanoparticles on the CO2 absorption inside a hollow fiber membrane contactor (HFMC). The distilled water and chemical system of 4-diethylamino-2-butanol (DEAB)-water nanofluid for CO2 absorption was studied. The considered drops were nanofluids containing carbon nanotube (CNT) and nanosilica (SiO2). A rigorous two-dimensional mathematical model for CO2 absorption from a N2/CO2 gas mixture was developed. The predicted results indicated that the injection of nanoparticles to distilled water and DEAB amine solution improves the CO2 absorption efficiency. Nanofluid of CNT represented better separation performance than nanosilica. Also, the CO2 absorption efficiency of nanofluids was enhanced with the increasing amine and nanoparticle concentration, liquid flow rate and also, decreasing the gas flow rate. Although increasing the liquid temperature decreased the physical absorption of CO2, it enhanced the chemical absorption of CO2 due to improvement of the reaction rates and diffusion coefficients.