| Autor: |
Lian, Jian-jun, Wu, Meng, Wu, Hong-yan, Liu, Yan-ting, Xu, Qing, Miao, Man-jun, Yang, Jian-hua, Mao, Ke-ke, Chen, Bo, Xue, Feng, Kong, Qiao-ping, Shang, Ming-hao, Li, Xiu-ling |
| Zdroj: |
Desalination & Water Treatment; July 2023, Vol. 299 Issue: 1 p137-153, 17p |
| Abstrakt: |
The significant increase in demand for molybdenum (Mo) resources has led to excessive molybdate (Mo(VI)) content in water, posing a challenge to the innovation of Mo(VI) removal technology in water bodies. Nanoscale iron sulfide (FeS) has an important effect on the environmental behavior of Mo(VI) in aquatic solutions. To address the issue of easy agglomeration and poor stability of FeS, zirconia sol-modified nanoscale iron sulfide (Zr-FeS) was synthesized, and the adsorption behavior of Zr-FeS on Mo(VI) from diverse aquatic solutions was also investigated in this study. The results showed that the removal rate of Mo(VI) was increased from 28.60% to 78.32% within pH value of 7.0 when Zr/Fe molar ratio was elevated from 0 to 0.5. Moreover, the Mo(VI) adsorption efficiency by Zr-FeS was closely related to pH values, and acid conditions were beneficial for Mo(VI) adsorption. The pseudo-second-order model demonstrated a better fit to the data compared to other models. The maximum adsorption capacity of Zr-FeS towards Mo(VI) value calculated by Langmuir isotherm model was 118.48 mg/g at 298 K. The thermodynamic analysis revealed that the adsorption process of Mo(VI) was endothermic, entropically favorable, and spontaneous in nature. Competing anions (e.g., PO43–, HCO3–, and SO42–) partially inhibited the adsorption process of Mo(VI) by Zr-FeS. While the process was less affected by dissolved oxygen and aging. The results of Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and density functional theory (DFT) calculations revealed that the main mechanisms for Mo(VI) removal were hydrogen bonding, electrostatic interaction and surface complexation. The high stability and fast adsorption rate indicated that Zr-FeS was a promising material to remove Mo(VI) from the aquatic solutions. |
| Databáze: |
Supplemental Index |
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