Three-dimension titanium phosphate aerogel for selective removal of radioactive strontium(II) from contaminated waters

Yiguo Meng; Youbin Wang; Zhenxiong Ye; Nannan Wang; Chunlin He; Yanqiu Zhu; Toyohisa Fujita; Hanyu Wu; Xinpeng Wang

doi:10.1016/j.jenvman.2022.116424

Three-dimension titanium phosphate aerogel for selective removal of radioactive strontium(II) from contaminated waters

J Environ Manage. 2023 Jan 1;325(Pt B):116424. doi: 10.1016/j.jenvman.2022.116424. Epub 2022 Oct 22.

Authors

Yiguo Meng¹, Youbin Wang¹, Zhenxiong Ye¹, Nannan Wang¹, Chunlin He¹, Yanqiu Zhu¹, Toyohisa Fujita¹, Hanyu Wu², Xinpeng Wang³

Affiliations

¹ MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, PR China.
² Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, PR China. Electronic address: wuhy76@mail.sysu.edu.cn.
³ MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials, Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials, School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, PR China. Electronic address: wangxinpeng@gxu.edu.cn.

PMID: 36283167
DOI: 10.1016/j.jenvman.2022.116424

Abstract

The effective removal of radioactive strontium (especially ⁹⁰Sr) from nuclear wastewater is crucial to environmental safety. Nevertheless, materials with excellent selectivity in Sr removal remain a challenge since the similarity with alkaline earth metal ions in the liquid phase. In this work, a novel titanium phosphate (TiP) aerogel was investigated for Sr(II) removal from the radioactive wastewater based on the sol-gel method and supercritical drying technique. The TiP aerogel has amorphous, three-dimensional and mesoporous structures with abundant phosphate groups, which was confirmed by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), atomic force microscope (AFM) and Fourier transform infrared spectroscopy (FT-IR). The adsorbent exhibited high efficiency and selectivity for the removal of Sr(II) with an extensive distribution coefficient up to 4740.03 mL/g. The adsorption equilibrium reached within 10 min and the maximum adsorption capacity was 373.6 mg/g at pH 5. And the kinetics and thermodynamics data fitted well with the pseudo-second-order model and Langmuir model respectively. It can be attributed to the rapid trapping and slow intraparticle diffusion of Sr(II) inside the mesoporous channels of the TiP aerogel. Furthermore, TiP aerogel exhibited over 80% removal for 50 mg/L Sr²⁺ in real water systems (seawater, lake water and tap water). X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy revealed that strong ionic bonding formed during Sr(II) adsorption with the phosphate group on TiP aerogel. These results indicated that TiP aerogel is a promising high-capacity adsorbent for the effective and selective capture of Sr(II) from radioactive wastewater.

Keywords: Aerogel; Radioactive wastewater; Removal; Strontium; Titanium phosphate.

MeSH terms

Adsorption
Hydrogen-Ion Concentration
Kinetics
Phosphates
Spectroscopy, Fourier Transform Infrared
Strontium* / analysis
Wastewater / chemistry
Water / chemistry
Water Pollutants, Chemical* / chemistry

Substances

Strontium
titanium phosphate
Waste Water
Water Pollutants, Chemical
Water
Phosphates