Wen Y, Wu Y, Xu L. Radiation Resistance and Adsorption Behavior of Aluminum Hexacyanoferrate for Pd.
TOXICS 2023;
11:321. [PMID:
37112548 PMCID:
PMC10143040 DOI:
10.3390/toxics11040321]
[Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 03/26/2023] [Accepted: 03/27/2023] [Indexed: 06/19/2023]
Abstract
Irradiation resistance is important for adsorbents used in radioactive environments such as high-level liquid waste. In this work, a silica-based composite adsorbent (KAlFe(CN)6/SiO2) was synthesized and γ-irradiated from 10 to 1000 kGy. The angles of the main X-ray diffraction peaks slightly decreased with the increase in irradiation dose, and a minor decomposition of CN- occurred after irradiation to 1000 kGy, indicating that the KAlFe(CN)6/SiO2 adsorbent could preserve structural integrity with a dose below 100 kGy. In 1 to 7 M HNO3, the adsorption ability of the irradiated KAlFe(CN)6/SiO2 remained performant, with a higher Kd than 1625 cm3 g-1. The adsorption equilibrium of Pd(II) in 3 M HNO3 was attained within 45 min before and after irradiation. The maximal adsorption capacity Qe of the irradiated KAlFe(CN)6/SiO2 on Pd(II) ranged from 45.1 to 48.1 mg g-1. A 1.2% relative drop in Qe was observed after 100 kGy irradiation, showing that γ-irradiation lower than 100 kGy insignificantly affected the adsorption capacity of KAlFe(CN)6/SiO2. Calculating and comparing the structures and free energies of different adsorption products via the density functional theory (DFT) method showed that KAlFe(CN)6/SiO2 was more inclined to completely adsorb Pd(II) and spontaneously generate Pd[AlFe(CN)6]2.
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