Sono-hollow fiber membrane contactors: A new approach for CO2 separation by physical/chemical absorbents

Abstract

Herein, the nano adsorbents of Fe3O4 and Fe3O4@SiO2–NH2 were first synthesized and then dispersed in distilled water as a base fluid for Carbon dioxide (CO2) separation from a gas stream using a polypropylene hollow fiber membrane contactor (PP HFMC) and the separation experiment was performed under non-ultrasonic/ultrasonic irradiation for the first time. The impacts of varying liquid and gas flow rates, nanoparticles (NPs) loading, absorbents viscosity, NPs stability, and ultrasonic irradiation intensity were evaluated on the performance of Fe3O4 and Fe3O4@SiO2–NH2 nanofluids in CO2 separation. According to the obtained results, Fe3O4@SiO2–NH2 nanofluid was considerably powerful compared to Fe3O4 nanofluid due to the advantage of chemical reaction with CO2. Furthermore, ultrasound irradiation effectively raised the CO2 absorption capacity of Fe3O4 and Fe3O4@SiO2–NH2 nanofluids up to 13.37 and 16.41%, respectively. Ultimately, at the best operational condition, the CO2 separation enhancement factors of 58.44 and 84.45% were achieved by Fe3O4@SiO2–NH2 nanofluid under non-ultrasonic irradiation and ultrasonic irradiation conditions.