Competitive adsorption of VOCs (benzene, xylene and ethylbenzene) with Fe3O4@SiO2-NH@BENZOPHENONE magnetic nanoadsorbents

Abstract

Volatile organic compounds (VOCs), which are toxic, mutagenic and carcinogenic, are considered a critical factor for air pollution and cause serious harm to the eco-environment and human health. In this study, Fe3O4, Fe3O4@SiO2-NH2, Fe3O4@SiO2-NH@BENZOFENONE were synthesized as new magnetic nanoadsorbents (MNAs) and used for the first time in the removal of gas-phase benzene, xylene and ethylbenzene. The synthesised MNAs were characterized by SEM-EDS, TEM, FTIR, XRD, VSM, TGA and BET analyses. The characterization results showed that the MNAs have mesoporous structure, type IV physioresorption and type H3 hysteresis loop character. In order to clarify the comparative and competitive adsorption behaviour, the adsorption capacity of Fe3O4@SiO2-NH@BENZOFENONE MNA was found to be in the order of xylene > ethylbenzene > benzene in both single, binary and ternary component systems. The adsorption kinetics of benzene, xylene and ethylbenzene with Fe3O4@SiO2-NH@BENZOFENONE MNA were found to be governed by multistep mechanisms. Fe3O4@SiO2-NH@BENZOFENONE MNA showed reuse efficiencies of 83.07%, 84.35% and 82.99% after 5 cycles for benzene, xylene and ethylbenzene respectively. In the framework of the results, Fe3O4@SiO2-NH@BENZOPHENONE MNA, which has a high potential in terms of both adsorption capacity and reuse efficiency, is proposed as a promising adsorbent for the efficient removal of benzene, xylene and ethylbenzene.