Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Xin Zhong,Yuxin Liu,Tao Hou,Yuling Zhu,Baowei Hu
The efficient, safe, low-cost and easy to treatment of uranium(U(VI))-containing wastewater is still an imminent problem. Herein, the hierarchical hollow-spherical bismuth tungstate (Bi 2 WO 6 ) was prepared by hydrothermal method, and sufficiently characterized by morphology and photoelectrochemical properties. In this research, we not only discussed the adsorption performance of U(VI), but also investigated the photocatalytic reduction performance of U(VI), so as to provide technical support for the treatment of U(VI)-containing wastewater in the future. The adsorption procedure complied with the pseudo-second-order model, implying surface complexation or chemisorption . Besides, under visible-light irradiation lasting for 600 min, the photoreduction removal rate of U(VI) was 53% (just adding 2.0 mg Bi 2 WO 6 ), without adding the h + scavenger, due to the harvest absorption of solar energy, hierarchically porous structure and synergic effect of adsorption and photocatalysis . Furthermore, the adsorption mechanism and photocatalytic reduction mechanism of Bi 2 WO 6 for U(VI) were revealed. The metal 3O and O3H bonds in Bi 2 WO 6 crystal were the active coordination sites for U(VI) adsorption, while •O 2 − and e - were the main active species for U(VI) photocatalytic reduction. Although the mechanisms of adsorption and photocatalytic reactions were different, there was a synergistic effect in the process of practical for application removing U(VI) by Bi 2 WO 6 . Consequently, the hierarchical nanosheets-assembled Bi 2 WO 6 microspheres could be considered as a good candidate for visible-light-responsive photocatalyst in radioactive wastewater treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2023
·
IF 10.9
Yuanqing Wang,Yusong Pan,Hongwu Zhu,Yanlei Xiang,Rong Han,Run Huang,Chao Du,Chengling Pan
Environmental problems have become more and more serious with the continuous development of industrialized society. Especially, the problem of industrial wastewater has been a hot research issue in the field of catalytic degradation. Coupling photocatalysis and advanced oxidation processes (AOPs) is considered to be an efficient organic pollutant degradation technology due to its high efficiency, non-selectivity, and mild treatment conditions. In this article, the authors focused on the synthesis and characterization of Bismuth tungstate (Bi 2 WO 6 ) nanoflowers, which were prepared using a straightforward hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB) surfactant. To investigate the micro-morphology, crystal phase, surface chemical element states, and optical characteristics of the Bi 2 WO 6 nanoflowers, various methods such as X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and diffuse reflection spectroscopy (DRS) were used. The catalytic performance of the Bi 2 WO 6 nanoflowers was then investigated for degrading organic pollutants under different catalytic systems. The removal efficiency of Rhodamine B (RhB) was up to 96.39% within 40 min under vis/potassium monopersulfate triple salt (PMS)/ Bi 2 WO 6 system, which is obviously superior to that in both PMS/ Bi 2 WO 6 (38.77% in 40 min) and vis/Bi 2 WO 6 (31.82% in 40 min) systems, indicating that synergistic effects between visible-light irradiation and PMS accelerated the catalytic activity of Bi 2 WO 6 on the RhB degradation. The researchers also investigated the effect of ambient conditions on the catalytic performance of the systems, such as catalyst dosage, PMS concentration, pH value, and ion concentration. Interestingly, the vis/PMS/Bi 2 WO 6 system demonstrated high removal efficiency (up to 90%) despite changes in these parameters. However, the catalytic degradation rate ( k ) was influenced by these parameters in this system. Conversely, the environmental parameters have obvious influence on the catalytic degradation rate ( k ) under vis/PMS/ Bi 2 WO 6 system. The results showed that when the catalyst dosage and PMS concentration increased, so did the K value. On the other hand, the K value increased firstly and then decreased with the rise of pH value in the catalytic system. And the catalytic degradation rate reached its maximum value (0.1502 min −1 ) at pH = 7 in the catalytic system. Interestingly, the presence of Cl − in the system would be beneficial for promoting the catalytic degradation efficiency. Conversely, the existence of
CO 3 2 - in the system would obviously inhibit the catalytic degradation efficiency. The result of the cycling experiments also verified that the catalyst possessed excellent stability for the degradation of organic dyes. Furthermore, the researchers conducted quenching experiments and EPR (electron paramagnetic resonance) tests, which revealed the crucial roles of superoxide radicals (
⋅ O 2 - ) and singlet oxygen ( 1 O 2 ) in the degradation of organic pollutants. Overall, the excellent catalytic activity of Bi 2 WO 6 in the vis/PMS synergistic catalytic system was attributed to its outstanding visible-light-response photocatalysis activity and the superior ability of bismuth ions in activating PMS. Download: Download high-res image (108KB) Download: Download full-size image
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 41
·16105-16118
·
IF 4.5
Wang Shi,Dang Chenyang,Li Mengli,Gu Li,Wu Jun,Cao Xuebo
Efficiently harnessing abundant and renewable solar energy for sustainable and continuous municipal sewage or industrial outlet water treatment to deal with water crisis has been an urgency for researchers in the past decades. Herein, a scalable and cost-effective solar steam device built up of surface-carbonized cane (CC) and Bi 2 WO 6 nanoflower photocatalyst is demonstrated, which exhibits high efficiency for concurrent waste water treatment and solar-to-water evaporation. CC is chosen as artificial core component in this system due to its nature-made periodic micro-/nanochannels, low heat conductivity, which contributes to extraordinary water transport, evaporation capacity and thermal management. Compared to natural cane, CC exhibits remarkably enhanced light absorption capacity and solar-to-water evaporation efficiency. Moreover, through the modification of Bi 2 WO 6 nanoflower, the system shows an optimized utilization of absorbed photons for high redox charge carriers in photocatalytic degradation and heat generation to promote the water treatment, leading to enhanced pollutant degradation efficiency. The steam generation performance reaches up to 1.417 kg·m −2 ·h −1 and solar-to-water evaporation efficiency of ~ 91.7% under 1 sun irradiation, which are among the highest values in the literatures. Continuous water purification and freshwater production from municipal sewage are also carried out in a home-made tandem system. Graphical abstract
研究领域:
环境科学
·
材料工程
·
可再生能源
·
光催化
·
水净化技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）