Congcong Ding,Wencai Cheng,Yubing Sun,Xiangke Wang
This article has been retracted: please see Elsevier Policy on Article Withdrawal ( https://www.elsevier.com/about/our-business/policies/article-withdrawal ). This article has been retracted at the request of the Executive Editor-in-Chief. Concern was raised about the EDX spectra shown by the insets of Figure 1D and the top two XPS spectra of Figure 9A (Fe 0 pH 3.5 and Fe 0 + B. Subtilis pH 3.5), as well as the FTIR spectra from Figure S6 and the XPS spectra from Figure S7B-E, which contained features and noise that indicated data fabrication. The corresponding authors were not able to provide reasonable explanations for these features and the Editor decided to retract the article. Moreover, the top EDX spectrum shown by the insets of Figure 1D is highly similar to the spectrum shown by the inset of Figure 1C of the article that the authors have previously published in the Journal of Hazardous Materials 280 (2014) 399–408 http://dx.doi.org/10.1016/j.jhazmat.2014.08.023 . One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents an abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
Ning Liu,Rumin Li,Dalei Song,Qi Liu,Jiahui Zhu,Jing Yu,Ying Li,Hongsen Zhang,Jun Wang
The extraction of uranium (VI) from uranium solutions is an attractive means in the context of increasing demand for uranium resources. Multiple photocatalysis can convert uranyl ions to UO2 precipitation by adjusting the valence of uranium species, which makes it one of the effective means of uranium extraction. In this paper, LDHS@TCN composites were prepared by in-situ growth method, and the II-scheme heterojunction photocatalyst was successfully constructed. The LDHS@TCN composites has photo-assisted uranium reduction ability, and the photo-assisted uranium extraction reaches 1719.12 mg g −1 . In addition, XPS and DFT calculations were used to verify the formation mechanism of II-scheme heterojunction and the photoelectron transfer pathway during the reduction of U(VI) to U(IV).
The reduction behaviors of U(VI) ions in nitric acid media were investigated electrochemically by cyclic voltammetrys (CVs) and square wave voltammetrys (SWVs). The electrochemical redox reactions of uranium between different oxidation states was found to proceed quasi-reversibly at 295 K. At low nitric acid concentrations and in the absence of additional chemical reductant, the reduction of U(VI) was found to be diffusion controlled. The diffusion coefficient of U(VI) was determined to be 3.30–8.83 × 10 −6 cm s −1 and the activation energy for the diffusion of U(VI) was calculated as 23 kJ mol −1 by cyclic voltammetry at different temperatures. The reduction of U(VI) at relatively high nitric acid concentrations was further studied by chemical reduction (hydroxylamine, N,N-diethylhydroxylamine and acetaldoxime), potentiostatic/galvanostatic electrolysis, as well as the two ways combined (electrolysis in the presence of chemical reductants). No obvious reduction of U(VI) was observed by absorption spectroscopy when only electrolysis or chemical reductants were used. In contrast, U(VI) could be obviously reduced to U(IV) by electrolysis in the presence of chemical reductants. Moreover, hydroxylamine was found to be the best choice among the three chemical reductants used as holding reductant to ensure efficient reduction of U(VI) by electrolysis. Temperature has mixed effect on the electrolytic reduction rate as evaluated by absorption spectra.
Feng He,Qianxiang Xiao,Yin Chen,Hongqing Wang,Xiangke Wang
In the photoreduction of U(VI), protective gases and additional sacrificial agents are still the major obstacles. Herein, we developed an oxygen-deficient WO x /g-C 3 N 4 catalyst for the simultaneous reduction of U(VI) and preparation of benzaldehyde by selective oxidation of benzyl alcohol without protective gases and sacrificial agents. The removal of U(VI) by WO x /g-C 3 N 4 could reach 98.5% and the conversion of benzyl alcohol was nearly 32% with a selectivity close to 100%. Compared with single g-C 3 N 4 and defect-free WO 3 , the photoreduction activity of WO x /g-C 3 N 4 was 10.4 and 7 times higher, respectively. Besides, the role of oxygen and oxygen defects was explored. Owing to oxygen defects in the catalyst, oxygen was adsorbed on the oxidation end (WO x ) of the catalyst and activated without entering the reduction end to interfere with the photoreduction of U(VI), while favoring the generation of •O 2 - to improve the selectivity of benzaldehyde. Finally, a new mechanism was proposed.
危险品化学品经营许可证（带存储）