Efficient Selective Adsorption of Rubidium and Cesium from Practical Brine Using a Metal-Organic Framework-Based Magnetic Adsorbent

Yanping Wang; Qiongyuan Zhang; Kexin Li; Chunyan Wang; Dezhen Fang; Wenjie Han; Miao Lu; Xiushen Ye; Huifang Zhang; Haining Liu; Xiaoli Tan; Zhijian Wu

doi:10.1021/acs.langmuir.4c00647

Efficient Selective Adsorption of Rubidium and Cesium from Practical Brine Using a Metal-Organic Framework-Based Magnetic Adsorbent

Langmuir. 2024 Apr 23. doi: 10.1021/acs.langmuir.4c00647. Online ahead of print.

Authors

Yanping Wang^{1

2

3}, Qiongyuan Zhang^{1

2

3}, Kexin Li^{1

2}, Chunyan Wang^{1

2}, Dezhen Fang^{1

2

3}, Wenjie Han^{1

2}, Miao Lu^{1

2

3}, Xiushen Ye^{1

2}, Huifang Zhang^{1

2}, Haining Liu^{1

2}, Xiaoli Tan^{1

4}, Zhijian Wu^{1

2}

Affiliations

¹ Key Laboratory of Green and High-end Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, Qinghai 810008, PR China.
² Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province, Xining, Qinghai 810008, PR China.
³ University of Chinese Academy of Sciences, Beijing 100049, PR China.
⁴ School of Environment and Chemical Engineering, North China Electric Power University, Beijing 102206, PR China.

PMID: 38654502
DOI: 10.1021/acs.langmuir.4c00647

Abstract

Rubidium (Rb) and cesium (Cs) have important applications in highly technical fields. Salt lakes contain huge reserves of Rb and Cs with industrial significance, which can be utilized after extraction. In this study, a composite magnetic adsorbent (Fe₃O₄@ZIF-8@AMP, AMP = ammonium phosphomolybdate) was prepared and its adsorption properties for Rb⁺ and Cs⁺ were studied in simulated and practical brine. The structure of the adsorbent was characterized by SEM, XRD, N₂ adsorption-desorption, FT-IR, and vibrating sample magnetometer (VSM). The adsorbent had good adsorption affinity for Rb⁺ and Cs⁺. The Langmuir model and pseudo-second-order dynamics described the adsorbing isotherm and kinetic dates, respectively. The adsorption capacity and adsorption rate of Fe₃O₄@ZIF-8@AMP were increased by 1.86- and 2.5-fold compared with those of powdered crystal AMP, owing to the large specific surface area and high dispersibility of the adsorbent in the solution. The adsorbent was rapidly separated from the solution within 17 s using an applied magnetic field owing to the good magnetic properties. The composite adsorbent selectively adsorbed Rb⁺ and Cs⁺ from the practical brine even in the presence of a large number of coexisting ions. The promising adsorbent can be used to extract Rb⁺ and Cs⁺ from aqueous solutions.