Investigation into the Effect of Adsorbed Water on Absorption of H2S in an MDEA Aqueous Solution Enhanced by ZnO Nanoparticles

Mengxi Zhao; Mengyu Ma

doi:10.1021/acsomega.5c02424

Investigation into the Effect of Adsorbed Water on Absorption of H₂S in an MDEA Aqueous Solution Enhanced by ZnO Nanoparticles

ACS Omega. 2025 Jun 12;10(24):25938-25950. doi: 10.1021/acsomega.5c02424. eCollection 2025 Jun 24.

Authors

Mengxi Zhao¹, Mengyu Ma¹

Affiliation

¹ School of Chemistry and Pharmaceutical Engineering, Huanghuai University, Zhumadian 463000, China.

Abstract

In order to study the influence of water adsorption properties of metal oxide nanoparticles on the removal of H₂S by MDEA, ZnO nanoparticles were modified. The modified ZnO nanofluids still had good stability after 30 days of standing. Meanwhile, the viscosity of modified ZnO nanofluids with good dispersion was slightly higher than that of ZnO nanofluids with the same concentration. However, the absorption capacity of modified ZnO nanofluids to H₂S was higher than that of the ZnO nanofluids. The saturated sulfur capacity of the 0.1 vol % modified ZnO nanofluid was 2.485 g/L and the penetration time was 220 min, and ZnS was generated after desulfurization, while the surface of ZnO nanoparticles had a little change. This indicated that the water film formed by introduction of a hydroxyl group could enhance the adsorption of H₂S by ZnO nanoparticles. Mass transfer coefficient measurement showed that the modified ZnO nanoparticles could enhance mass transfer by enhancing the shuttle effect, and the mass transfer coefficient reached the maximum value of 23.458 mmol/s m² kPa. Therefore, the hydrophilicity of ZnO nanoparticles could be improved by β-cyclodextrin modification, and then the adsorption and mass transfer of H₂S could be enhanced, to improve the H₂S removal ability of the MDEA aqueous solution.