Membrane Absorption Coupling Process for CO₂ Capture: Application of Water-Based ZnO, TiO₂, and Multi-Walled Carbon Nanotube Nanofluids

Abstract

In this work, stable water-based zinc oxide (ZnO), titania (TiO2), and multi-walled carbon nanotube (MWCNT) nanofluids are prepared and examined as CO2 absorbents in a polypropylene hollow fiber membrane contactor. Different operating variables, such as liquid flow rate, gas flow rate, and concentration of nanoparticles, and their effects on CO2 molar flux are investigated. The long-term stability of nanofluids is monitored using ultraviolet–visible spectroscopy. Also, ζ-potential measurements and sediment photography are applied to confirm the results of nanofluid stability. Dynamic light scattering is used to determine the size distribution of dispersed nanoparticles. The results show that the increase in the nanoparticle concentration to 0.15 wt % has a favorable effect on CO2 absorption efficiency as a result of the increase in Brownian motion and other related mechanisms. However, it adversely affects the CO2 absorption by lowering the nanofluid stability at higher concentrations. The obtained results reveal that ZnO nanofluid is the most effective nanofluid in all experimental conditions. At low liquid flow rates of about 10 mL/min, ZnO nanofluid could augment CO2 absorption efficiency by 130%, while both TiO2 and MWCNT nanofluids could enhance it by 60% with respect to distilled water. Possible mechanisms regarding mass transfer augmentation are also discussed.

Experimental study of carbon dioxide absorption by Fe2O3@glutamine/NMP nanofluid

“…Fe 2 O 3 @glutamine NPs were stable as twice as Fe 2 O 3 NPs and could be dispersed in NMP solution to the maximum of 0.05 wt.% without plummeting into the unstable range of zeta potential. According to the last literacy, irregular movements of NPs break large CO 2 bubbles into smaller ones, increasing the bubbles' surface area, and consequently the mass transfer of CO 2 (Bubble breaking theory)(Krishnamurthy et al 2006;Nabipour et al 2017;Zare et al 2019). The schematic of the de ned mechanisms is shown in Fig.4.In this study, it was tried to increase the CO 2 absorption capacity of the Fe 2 O 3 /NMP nano solution using glutamine amino acid.…”

Hollow Fiber Membrane Contactors in CO2 Desorption: A Review

“…144 The improvement of gas solubility into the absorbent by the addition of a third dispersed phase, i.e., nanoparticles, was investigated by several researchers. [145][146][147] However, a few studies have been conducted on CO2 desorption: J.W. Lee et al 148 and Lee et al 149 compared the CO2 regeneration efficiency of nanofluids (Al2O3 and SiO2 nanoparticles dispersed in DI water and methanol) and pure solvents.…”

Superhydrophobic Surface-Constructed Membrane Contactor with Hierarchical Lotus-Leaf-Like Interfaces for Efficient SO2 Capture

“…Recently, inorganic fillers have been incorporated into the polymer matrix for acid gas removal, , and inorganic particles in the membrane contactor show potential in combining the merits of the organic membrane contactor and inorganic membrane contactor such as excellent absorption fluxes, wetting resistances, and long-term stabilities . Leo et al incorporated SAPO-34 and POSS into the PVDF matrix and constructed pathways for gas diffusions, which improved gas absorption flux.…”

“…Rosli et al fabricated a membrane contactor by incorporating TS-530 silica nanoparticles into the PVDF polymer matrix, 24 and the surface of the membrane contactor was coated with polyethylene, which elevated the membrane hydrophobicity property PVDF) mixed matrix membrane contactors were fabricated by Xu et al, 34 and the as-prepared mixed matrix membrane contactor displayed the average pore size of 25 nm and the high WCA of 124°, which noticeably kept the membrane contactor from wetting. Recently, inorganic fillers have been incorporated into the polymer matrix for acid gas removal, 35,36 and inorganic particles in the membrane contactor show potential in combining the merits of the organic membrane contactor and inorganic membrane contactor such as excellent absorption fluxes, wetting resistances, and long-term stabilities. 21 Leo et al 37 incorporated SAPO-34 and POSS into the PVDF matrix and constructed pathways for gas diffusions, which improved gas absorption flux.…”