Enhanced selective separation of vanadium(V) and chromium(VI) using the CeO2 nanorod containing oxygen vacancies

• Published in: Environmental science and pollution research international Vol. 30; no. 27; pp. 70731 - 70741
• Main Authors: Lin, Ruixi, Li, Jiarong, Jing, Xuequan, Guo, Meina, Ren, Guoqing, Qin, Haonan, Yao, Zhangwei, Wan, Yinhua, Song, Weijie, Zeng, Huifeng, Yang, Feifei, Zhao, Da, Hu, Kang
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2023; Springer Nature B.V
• Subjects: Adsorption; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Cadmium; Cerium oxides; Chromium; Copper; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Ions; Manganese; Nanorods; Oxygen; Research Article; Selectivity; Separation; Vanadium; Waste Water Technology; Wastewater; Water Management; Water Pollution Control; Vanadium ions; Oxygen vacancies; Selective removal; CeO; nanorod
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-27415-1

Adsorption of vanadium from wastewater defends the environment from toxic ions and contributes to recover the valuable metal. However, it is still challenging for the separation of vanadium (V 5+ ) and chromium (Cr 6+ ) because of their similar properties. Herein, a kind of CeO 2 nanorod containing oxygen vacancies is facilely synthesized which displays ultra-high selectivity of V 5+ against various competitive ions (i.e., Fe, Mn, Cr, Ni, Cu, Zn, Ga, Cd, Ba, Pb, Mg, Be, and Co). Moreover, a large separation factor ( SF V/Cr ) of 114,169.14 for the selectivity of V 5+ is achieved at the Cr 6+ /V 5+ ratio of 80 with the trace amount of V 5+ (~ 1 mg/L). The results show that the process of V 5+ uptake is the monolayer homogeneous adsorption and is controlled by external and intraparticle diffusions. In addition, it also shows that V 5+ is reduced to V 3+ and V 4+ and then formation of V–O complexation. This work offers a novel CeO 2 nanorod material for efficient separation of V 5+ and Cr 6+ and also clarifies the mechanism of the V 5+ adsorption on the CeO 2 surface.