Constructing mesoporous phosphated titanium oxide for efficient Cr(III) removal

Wang Peng; Sun Du; Zhang Shaoning; Huang Xieyi; Bi Qingyuan; Qian Meng; Zhao Wei; Huang Fuqiang

doi:10.1016/j.jhazmat.2019.121278

Constructing mesoporous phosphated titanium oxide for efficient Cr(III) removal

J Hazard Mater. 2020 Feb 15:384:121278. doi: 10.1016/j.jhazmat.2019.121278. Epub 2019 Sep 23.

Authors

Wang Peng¹, Sun Du², Zhang Shaoning², Huang Xieyi², Bi Qingyuan², Qian Meng², Zhao Wei³, Huang Fuqiang⁴

Affiliations

¹ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 200031, PR China.
² State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, PR China.
³ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, PR China. Electronic address: zhaowei220@mail.sic.ac.cn.
⁴ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, PR China; Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China; Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, PR China; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 200031, PR China. Electronic address: huangfq@mail.sic.ac.cn.

PMID: 31581021
DOI: 10.1016/j.jhazmat.2019.121278

Abstract

Heavy metal removal by environmental-friendly nanostructured TiO₂ adsorbent is a promising strategy to facilitate wastewater treatment. Here, a boiling water synthetic approach is explored to prepare mesoporous phosphated TiO₂ (PTO) used for Cr(III) adsorption in polluted water. We obtain mesoporous 8-PTO (synthesized with 8% molar ratio of H₃PO₄) with a high specific surface area (278 m²/g), narrow size distribution (<5 nm), low pH_zpc (pH of zero point of charge) value (∼1.0), and abundant surface hydroxyl group, which is attributed to the introduction of H₃PO₄ during the hydrolysis process of TiCl₄ in boiling water. Importantly, the obtained 8-PTO shows better thermal stability than pure TiO₂ and retains mesoporous structure after thermal treatment owning to [PO₄] tetrahedral incorporated into the network of [TiO₆] octahedral. The optimized 8-PTO exhibits superior Cr(III) adsorption up to 92 mg/g in sewage, which makes it one of the best materials among TiO₂ adsorbent known for Cr(III) Removal (10-83 mg/g). Additionally, the as-prepared mesoporous 8-PTO adsorbent possesses an excellent reusability without significant degradation and can largely avoid the generation of secondary contaminants. A linear relationship (R² = 0.9985) between adsorption capacity and hydroxyl content percentage of different PTO samples is revealed, indicating that the surface hydroxyl groups play a decisive role in the adsorption process. This study provides a facile approach to synthesize high specific surface area mesoporous phosphated TiO₂ with rich surface functional groups for efficient Cr(III) removal in sewage.

Keywords: Adsorption; Adsorption capacity; Cr(III) ion; High specific surface area; Hydroxyl group; Mesoporous 8-PTO.

Publication types

Research Support, Non-U.S. Gov't