MOLECULES
·
2025
·Vol. 30
·期 7
·1533
·
IF 4.6
Yuyang Gan,Yimin Cai,Song Huang,Xiaowei Li,Wen Feng,Lihua Yuan
Nitrogen donor-based ligands are highly promising extractants for palladium separation from high-level liquid waste (HLLW). However, the electronic effect of these ligands, a critical factor influencing their complexation ability with Pd(II), remains largely unexplored. Herein, three picolinamide-based ligands were designed and synthesized, each featuring substituents with distinct electronic effects at thepara-position of the pyridine (electro-donating methoxyl group for L-I, hydrogen for L-II, and electro-withdrawing ester group for L-III). The concurrent processes of Pd(II) coordination and ligand protonation enable the manipulation of pyridine nitrogen electronegativity, resulting in a tunable Pd(II) extraction performance. Notably, L-I exhibits the highest extraction efficiency at low acidities (≤1 M HNO3) but the lowest extraction at high acidities (≥3 M HNO3), whereas L-III shows the poorest efficiency at low acidities but the best performance at high acidities. The Job plot analysis and ESI-HRMS results reveal a 1:1 and 2:1 (L/Pd) stoichiometry in the Pd(II) complexation process. The single crystal X-ray analysis of Pd(NO3)2(L-II)2complex confirms a four-coordinated Pd(II) center, with two pyridine nitrogen atoms and two monodentate nitrate oxygens forming a quadrangular geometry. Density functional theory (DFT) calculations further indicate that the formation of 2:1 (L/Pd) complexes is energetically favored, and the stronger basicity of the nitrogen atoms correlates with a higher Pd(II) binding affinity and increased susceptibility to protonation.
研究领域:
化学
·
环境科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Wentao Wang,Shichang Zhang,Lifeng Chen,Zengyuan Li,Kun Wu,Ye Zhang,Zhe Su,Xiangbiao Yin,Mohammed F. Hamza,Yuezhou Wei,Shunyan Ning
Palladium (Pd) in high level liquid waste (HLLW) is a valuable alternative resource besides its natural reserves. On the other hand, the presence of Pd has extremely negative impacts on the vitrification process of HLLW. To separate Pd from HLLW, a novel silica-based adsorbent named HEMAP/SiO 2 -P was designed and prepared by using 2-hydroxyethyl-2-methyl-2-propenoate phosphate as the functional group donor, dichloromethane as the diluent and styrene–divinylbenzene modified silica particle as the carrier. The experimental results reveal that HEMAP/SiO 2 -P possesses excellent adsorption selectivity ( SF Pd/other metals > 183.2) and large adsorption capacity (393.4 mg/g) towards Pd in 1 M HNO 3 solution. Moreover, column experiments show that the adsorbent can effectively separate Pd from other coexisting metal ions in simulated HLLW with the recovery yield of 99.4%. The experimental and characterization analyses as well as DFT calculations confirm that the adsorption mechanism involves ion exchange between Pd(II) and H + (in P-OH) accompanied by the transfer of charge.
研究领域:
化学工程
·
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Zhe Su,Shunyan Ning,Zengyuan Li,Shichang Zhang
A silica-polymer-based adsorbent ( iso Pentyl-BTBP/SiO 2 -P) was prepared via a vacuum impregnation method for efficient and continuous separation of palladium from complex systems. The results revealed that the distribution coefficient ( K d ) value of iso Pentyl-BTBP/SiO 2 -P toward Pd in 3 M HNO 3 solution was 5226 mL/g, with a maximum adsorption capacity of 31.7 mg/g. Besides, iso Pentyl-BTBP/SiO 2 -P exhibited a superior adsorption selectivity toward Pd to the other 14 coexisting interfering fission product ions, with the separation factor SF Pd/M value over 433 in 0.1–6 M HNO 3 solution. Moreover, column experiments results demonstrated that iso Pentyl-BTBP/SiO 2 -P can efficiently separate Pd with approximately 100% recovery, from simulated high level liquid waste (HLLW) solutions with multiple competing ions. Finally, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analysis results revealed strong interactions between nitrogen-containing functional groups (C-N C) and Pd throughout the adsorption process , wherein the NO 3 − acting as the counterions to balance the charge. In conclusion, iso Pentyl-BTBP/SiO 2 -P has shown promising applications for effectively separating Pd from multi-component and highly acidic environments.
研究领域:
化学工程
·
核化学与放射化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Hefang Liu,Shunyan Ning,Zengyuan Li,Shichang Zhang,Lifeng Chen,Xiangbiao Yin,Toyohisa Fujita,Yuezhou Wei
In this work, a novel silica-based N-donor ligand functional adsorbent (SiVpC) is prepared by in situ polymerization for the efficient separation of palladium from high level liquid waste (HLLW). The as-prepared SiVpC adsorbent is characterized by SEM-EDS, TGA, and BET. The effects of nitric acidity, SiVpC adsorbent dosage, time, temperature, and palladium ion concentration on the adsorption are investigated. Among the 12 typical fission product metal ions (Ru, Rh, La, Y, Pr, Ce, Sm, Nd, Gd, Eu, Zr, Mo) existing in HLLW, SiVpC adsorbent can selectively adsorb palladium ( SF Pd/other metals = 137.6) in 0.5 M HNO 3 solution. The adsorptio kinetics of Pd(II) are consistent with the pseudo-second-order model, reaching equilibrium within 120 min. The maximum adsorption capacity is 38.4 mg/g in 0.5 M HNO 3 , and the adsorption process is consistent with the Langmuir model. The adsorbed palladium can be completely desorbed with 0.5 M HNO 3 -0.5 M Thiourea. Furthermore, SiVpC adsorbent remains good performance after five adsorption–desorption cycles, which indicates good reusability. The adsorption mechanism of SiVpC adsorbent on palladium is analyzed by FT-IR and XPS that N-containing functional groups on the ligand are coordinated with palladium, which is also further verified by DFT calculations. In addition, through the column chromatography separation system, SiVpC adsorbent can efficiently adsorb palladium from HLLW and the adsorbed palladium can be desorbed with 0.5 M HNO 3 -0.5 M thiourea solution, which has great application potential.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Junli Wang,Chen Luo,Wentao Wang,Hui Wang,Jiaxuan Shi,Taihong Yan,Meiwen Cao,Jianwei Li
The effective separation of palladium isotopes from high-level radioactive waste offers significant advantages, not only in ensuring the safe management and disposal of radioactive materials but also in addressing the scarcity of noble metals. In this study, a covalent organic framework (COF-SSH) modified with thiol and thioether groups is synthesized for the purpose of palladium separation. The experimental results demonstrate that the adsorption of Pd(II) occurs rapidly, reaching equilibrium within just 10 min. The adsorption isotherm for Pd(II) aligns well with the Langmuir model, revealing a maximum adsorption capacity of 420.2 mg/g at 3 M HNO 3 . Through Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Photoelectron Spectroscopy (XPS), and Density Functional Theory (DFT) analyses, the interaction between Pd and S atoms as being crucial for the adsorption process is identified. Moreover, COF-SSH exhibits exceptional selectivity for Pd(II) in simulated nuclear wastewater and maintains its performance throughout six consecutive adsorption and regeneration cycles. These results suggest that COF-SSH is a promising adsorbent for palladium separation, offering both acid resistance and high selectivity, making it a valuable candidate to the field of radioactive waste management and noble metal recovery.
研究领域:
材料科学
·
核化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）