Journal of Cleaner Production
·
2022
·
IF 11.072
Wenju Tao,Jiaxin Yang,Zhibo Liu,Yifan Zhang,Liyu Chen,Shaohua Wu,Jinbo Qiao,Zhengduo Xue,Zhaowen Wang
The recovery and utilization of by-product coal fly ash (CFA) in high-value-added thermal power plants is of great significance. This research focused on producing high-value-added Al–Si master alloy by aluminothermic reduction with coal fly ash as the raw material. The effects of reduction time and reducing agent amount on thermal reduction products were investigated using the single factor method. X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) results showed that Al, Si, and a small amount of Fe were the main components of the alloy. With an increase in reaction time, the mass fraction of Si in the product increased from 4.41% to 9.93%. Besides, the molten salt after thermal reduction was recovered by the electrochemical reduction process. The results showed that a longer electrolysis time is more conducive to improving the recovery of Si and Al. The results of cyclic voltammetry and electrodeposition showed that Si would be reduced in a multi-step process. Combined with thermal reduction and electrochemical secondary recovery process , the comprehensive recovery of Al and Si in fly ash could reach 87.33% and 84.02%, respectively.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
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IF 12.2
Xu Yin,Jiatian Yu,Zhifeng Gao,Wei Li,Kajia Wei,Yun Jiang,Yonghao Zhang,Haoming Chen,Weiqing Han
Bromate (BrO 3 – ) is a common by-product of advanced oxidation water treatment processes. In this study, a catalyst combining MXene and Pd was synthesized to eliminate BrO 3 – by electrochemical reduction in flow-through mode. The fabricated Ti/Pd@MXene filter showed superior activity for BrO 3 – reduction compared with Ti/MXene filter. A satisfactory BrO 3 − removal performance by Ti/Pd@MXene filter was obtained at pH values of 5–7 with a current density of 1.0–2.5 mA·cm –2 . The mechanism explored by quenching experiments and EPR analysis demonstrated that atomic hydrogen (H*)-mediated reduction was dominant in the Ti/Pd@MXene filter system and contributed to 84.2 % of the BrO 3 − removal, which was greater than that of Ti (7.1 %) and Ti/MXene (43.9 %). DFT calculations revealed the introduction of Pd nanoparticles on MXene lowered the energy barrier for generating H* from OH* -H* , thus boosting H* formation. Furthermore, the Ti/Pd@MXene filter had favorable stability and applicability, and nearly 90 % of BrO 3 − could be eliminated in different water matrices. Moreover, energy consumption of the Ti/Pd@MXene filter was more competitive than that previously reported (0.348 kWh·mmol −1 ), especially for high BrO 3 − removal (≥75 %). This work highlighted an effective flow-through electrocatalytic filter to induce H* -mediated electrochemical reduction of BrO 3 − .
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2022
·Vol. 169
·期 5
·052504
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IF 4.386
Kun Zhao,Kejia Liu
The formation of CaTiO3 during the electro-reduction of TiO2 pellets in CaCl2-based molten salts is unavoidable. So in present paper, the electro-deoxidation of porous CaTiO3 pellets was investigated. Cyclic voltammetry and constant potential electrolysis experiments were conducted to gain insight into the electro-deoxidation mechanism. From the results, two new reduction pathways of the porous CaTiO3 pellets were determined. The main factor influencing the reduction pathways is the porosity. When the porosity is low, CaTiO3 is directly reduced into TiO. With the porosity increases, some CaTiO3 will firstly be reduced into CaTi2O4 and then the CaTi2O4 is further reduced into TiO. The effect of the potential applied on the cathode on the possible reduction limit of the sample was discussed. The results indicated that the more negative the potential is, the faster the deoxidation rate is and the lower the deoxidation limit is. Only when the applied potential is more negative than −1.6 V vs Ag+/Ag, low-oxygen titanium (the oxygen content is lower than 1%) can be obtained in our experimental conditions. In addition, the microstructural kinetics of phase transformations during reduction of the CaTiO3 pellets were also discussed.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
MATERIALS TRANSACTIONS
·
2017
·Vol. 58
·期 3
·395-399
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IF 0.713
Xiaolong Liu,Chao Huang,Bing Li
In this paper, the cyclic voltammetry was applied to investigate the electrochemical reduction processes of Nd(III) ions in NdF3-LiF melts with or without excessive metal Nd. Equilibrium experiments were carried out in NdF3-LiF melts with excessive spheric metal Nd to investigate the relationship between the NdF3:LiF mass ratio and NdF2 concentration. Electrolysis experiments were performed in NdF3-LiF-Nd2O3 melts with different NdF3:LiF mass ratios to explore the relationship between the NdF2 concentration and the current efficiency.The results indicated that Nd(III) ions in the melts were reduced in two steps, i.e., Nd(III)→Nd(II) and Nd(II)→Nd(0). NdF2 could be formed by the comproportionation reaction between Nd(III) and Nd(0) and could stably exist in NdF3-LiF melts containing metal Nd(0). NdF2 mass concentration in the melts decreased from 45.5% to 36.4% with the increase of NdF3-LiF mass ratio from 7:3 to 9:1 in NdF3-LiF melts containing excessive spheric metal Nd, which resulted in a higher current efficiency during the electrolysis. And the highest current efficiency of about 50% for Nd extraction has been obtained by electrolysis in NdF3-LiF (9:1 mass ratio) melts with Nd2O3 (2%, mass concentration) at 1423 K.
研究领域:
冶金学
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电化学
✓ 已验证
DOI
PubMed
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
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IF 15.7
Guo Hongliang,Hu Enmin,Wang Yihao,Ou Zhenhong,Huang Bichu,Lei Jia,Liu Huanhuan,He Rong,Zhu Wenkun
Electrochemical extraction of uranium from seawater is a promising strategy for the sustainable supply of nuclear fuel, whereas the current progress suffers from the co-deposition of impurities. Herein, we construct a synergistic coordination-reduction interface in CMOS@NSF, achieving electrochemical extraction of black UO 2 product from seawater. The internal sulfur of CoMoOS tailors the electron distribution, resulting in the electron accumulation of terminal O sites for strong uranyl binding. Meanwhile, the interfacial connection of CoMoOS with Ni 3 S 2 accelerates the electron transfer and promoted the reductive properties. Such synergistic coordination-reduction interface ensures the formation and preservation of tetravalent uranium, preventing the co-deposition of alkalis in crystalline transformation. From natural seawater, CMOS@NSF exhibits an electrochemical extraction capacity of 2.65 mg g −1 d −1 with black UO 2 solid products as final products. This work provides an efficient strategy for the electrochemical uranium extraction from seawater with low impurities.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHEMISTRY COMMUNICATIONS
·
2021
·
IF 4.724
Liwen Zhang,Xiaoli Xi,Zuoren Nie
A new electrochemical method for efficient and green recovery of cemented carbide in a molten salt is described. Tungsten powder is the main product when recovering cemented carbide by molten salt electrolysis. However, the main purpose of tungsten powder is to make tungsten carbide. Based on this, a new method for preparing tungsten carbide by in situ reduction was developed. Pure tungsten carbide powder was successfully prepared in situ by pulse electrolysis in a NaF–KF molten salt system at 1073 K. This not only effectively recovers the spent cemented carbide, but also enriches the product system and optimizes the method for preparation of tungsten carbide powder.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2020
·Vol. 14
·期 5
·813-823
·
IF 3.552
Wang Mengyun,Zhang Shengbo,Li Mei,Han Aiguo,Zhu Xinli,Ge Qingfeng,Han Jinyu,Wang Hua
Novel, hierarchical, flower-like Ag/Cu 2 O and Au/Cu 2 O nanostructures were successfully fabricated and applied as efficient electrocatalysts for the electrochemical reduction of CO 2 . Cu 2 O nanospheres with a uniform size of ∼180 nm were initially synthesized. Thereafter, Cu 2 O was used as a sacrificial template to prepare a series of Ag/Cu2O composites through galvanic replacement. By varying the Ag/Cu atomic ratio, Ag 0.125 /Cu 2 O, having a hierarchical, flower-like nanostructure with intersecting Ag nanoflakes encompassing an inner Cu 2 O sphere, was prepared. The as-prepared Ag x /Cu 2 O samples presented higher Faradaic efficiencies (FE) for CO and relatively suppressed H 2 evolution than the parent Cu 2 O nanospheres due to the combination of Ag with Cu 2 O in the former. Notably, the highest CO evolution rate was achieved with Ag 0.125 /Cu 2 O due to the larger electroactive surface area furnished by the hierarchical structure. The same hierarchical flower-like structure was also obtained for the Au 0.6 /Cu 2 O composite, where the FE CO (10%) was even higher than that of Ag 0.125 /Cu 2 O. Importantly, the results reveal that Ag 0.125 /Cu 2 O and Au 0.6 /Cu 2 O both exhibit remarkably improved stability relative to Cu 2 O. This study presents a facile method of developing hierarchical metal-oxide composites as efficient and stable electrocatalysts for the electrochemical reduction of CO 2 .
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Tian-Wen Jiang,Xianxian Qin,Ke Ye,Wei-Yi Zhang,Hong Li,Wenhui Liu,Shengjuan Huo,Xia-Guang Zhang,Kun Jiang,Wen-Bin Cai
Electrochemical CO 2 reduction reaction to formate (CO 2 RRTF) on Pd-based surfaces merits very low overpotentials, yet is challenged with identification of a high-performance catalyst and validation of the reaction pathway. In this work, an interactive study of catalyst and mechanism is presented to address the above bottleneck. On one hand, inspired by preliminary mechanistic understanding of HCOOH ↔ CO 2 interconversion at Pd surfaces, a Bi-modified Pd/C with the known high performance towards formic acid dehydrogenation (FAD) is elected as the prototype candidate catalyst for CO 2 RRTF, exhibiting indeed significantly higher activity, selectivity, durability and extended working potentials. On the other hand, the CO 2 chemical hydrogenation mechanism is clarified with monodentate formate being the key intermediate for CO 2 RRTF on Pd surfaces, by applying isotope labeled ATR-SEIRAS measurement and kinetic analysis in conjunction with DFT calculations. The research paradigm facilitates locating efficient catalysts and advancing mechanistic study for CO 2 RRTF on Pd surfaces and beyond.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Henan Zhang,Kewei Jiang,Wantong Li,Qi Liu,Jing Yu,Jiahui Zhu,Yongde Yan,Milin Zhang,Jun Wang
The effective extraction of neutron poison samarium from nuclear waste to prevent reactions with metallic uranium is crucial for the sustainable development of nuclear energy. The electrochemical recovery of samarium on the liquid gallium cathode from the NaCl-2CsCl molten salts has been investigated by a variety of electrochemical techniques, and its electrochemical reduction properties and kinetic parameters have been provided. It was revealed that the reduction reaction on the Mo cathode of Ga(III) to Ga(0) and Sm(III) to Sm(II) is a two-step and one-step reaction process, respectively, and both reactions are reversible. The diffusion coefficients of Ga(III)/Ga(II) and Sm(III)/Sm(II) were identified, and the activation energies were 20.07 and 42.96 kJ mol–1, respectively. Simultaneously, the codeposition mechanism of Ga(III) and Sm(III) on the Mo cathode was systematically investigated, and the potential and types of formation of binary intermetallic compounds were explored. Subsequently, it was determined that there are two main reaction processes for Sm(III) on the liquid Ga cathode, and the deposition potential of Sm becomes more positive due to the formation of the alloy. The exchange current density values of Sm(III)/Sm(Ga) obtained by both linear polarity (LP) and Tafel techniques increased with temperature, meanwhile the charge transfer resistance decreased, as well as the transfer coefficient. In addition, the apparent electrode potential of Sm(III)/Sm(Ga) was also calculated. Based on the electrochemical analysis, the fission element Sm was deposited on the liquid Ga cathode by potentiostatic electrolysis at a suitable potential, and the alloy products were verified by X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. Ultimately, the highest separation efficiency of Sm on the liquid Ga cathode reached 92.43% according to the analysis of inductively coupled plasma atomic emission spectrometry (ICP-AES) results.
研究领域:
核能工程
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电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Huawang Zhao,Yuxin Xie,Bihong Lv,Guohua Jing,Yongdan Li
The CO 2 electrochemical reduction reactions (CO 2 ER) to produce high-value formate are crucial for closing the anthropogenic CO 2 cycle. Modulating the adsorption energy between *OCHO and Bi atoms in Bi-based catalysts could enhance both the activity and selectivity for formate formation. Here, a Bi/BiOBr nanosheet with highly dispersed Bi single atoms in intercalations was synthesized through NaBH 4 treatment of BiOBr, which retained the intercalated Bi atoms after electrolysis (Bi/BiOBr-D). The intercalated Bi atoms optimize the Bi-6p band center (0.016 eV) and charge distribution in Bi/BiOBr-D, enhancing the coupling between the O-2p orbitals of *OCHO and the Bi-6p orbitals as well as the electron transfer dynamics between Bi and the *OCHO intermediate, which improves the stability of the *OCHO intermediate during CO 2 ER. Further studies demonstrate that enhanced *OCHO adsorption reduces the Gibbs free energy barrier for the CO 2 →*OCHO process and suppressing the formation of the *H intermediate. Those advantages lead to high selectivity (FE of 96.83 %) in H-type cell, and excellent activity (j HCOO- of 815 mA/cm²) and productivity (15.22 mmol/h·cm²) in flow cell for formate production over Bi/BiOBr-D sample.
研究领域:
材料科学
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电化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Liqi Zhang,Xu Zhang,Bowen Huang,Yusheng Yang,Zengwu Zhao
Titanium is an excellent structural and functional material . At present, the production of titanium has long process cycle, high energy consumption, serious pollution and other characteristics, so the development of low-cost titanium production methods has extremely far-reaching significance. In this work, the electrochemical reduction process of Ti(IV) and Ti(II) in the CaF 2 -CaO melt were investigated by cyclic voltammetry and square wave voltammetry measurements at 1740 K, respectively. In the CaF 2 -CaO-5 wt% TiO 2 melt, Ti(IV) ions were reduced to Ti by one step. One measure was taken to lower the valence state of Ti ions : Ti(IV) ions in the melt was changed to Ti(II) by adding Ti 0 . Ti(IV) ions were reduced in two steps: in the CaF 2 -CaO-5 wt% TiO 2 -Ti 0 melt, Ti(IV) → Ti(II) and Ti(II) → Ti, respectively, and in the CaF 2 -CaO-5 wt% TiO, the Ti(II) ions were reduced in a single step: Ti(II) → Ti. It was found that both migration and mass transfer affected the reduction processes. In contrast to the Ti(IV) reduction to Ti process, the Ti(II) reduction to Ti process showed a higher diffusion rate. Electrolytes and electrodes were analyzed after titanium electrodeposition by XRD . It was found that there were no metal titanium was detected in the electrolyte placed close to the cathode after electrodeposition . It believed that the formed metallic Ti reacted with dissolved O 2- in the melt to form TiO. The reduction process of Ti(IV) on the iron electrode was investigated, the metal Ti was reduced by alloying process, the oxidation of Ti was hindered, there was a dense structure layer of CaTiO 3 outside the reduced metal Ti that prevented the ions transfer and affected the Ti(IV) ions migration process, which might be the main factor that the Ti(IV) reduction process was controlled by migration. The lower valence state of Ti in the melt promoted the formation of Ca 2 TiO 4 , which increased the ion migration rate and decreased the mass transfer rate. It was suggested that titanium or titanium alloys may be prepared by reducing the valence of Ti(IV) in minerals and altering the melt composition. It is feasible to prepare titanium and titanium alloys by MOE short process using ore as raw material.
研究领域:
冶金学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RESOURCES CONSERVATION AND RECYCLING
·
2021
·
IF 10.204
Liming Yang,Genping Yi,Bo Wang,Penghui Shao,Yufa Feng,Yanbiao Liu,Kai Yu,Fuqiang Liu,Lingling Liu,Xubiao Luo,Shenglian Luo
Simultaneous recovery and value-added conversion of hazardous heavy metal ions from complex wastewater sources is of great significance yet challenging. Herein, we demonstrate that highly toxic antimonite Sb(III) could be effectively recovered from antimony (Sb) mine flotation wastewater and converted into high-value-added metallic Sb using a novel facile atomic H* enhanced electrochemical reduction avenue coupled with thermal reduction by H 2 gas. The high production of atomic H* generated from the electrochemical cathode with an optimum reduction potential of –1.2 V vs . Ag/AgCl, which is lower than the Sb(III) reduction potential of –1.0 V, might be attributable to the superior Sb recovery capabilities. Furthermore, the metallic Sb concentration at –1.2 V was 14.43 times greater than at –1.0 V due to the strong reductivity of atomic H*. In addition, Sb(III) removal efficiency was found to be as high as 98.52%, with a metallic Sb recovery rate of up to 1.67 mg min –1 . The efficiency of Sb(III) recovery was demonstrated throughout a wide pH range, with metallic Sb being the main product, independent of the presence of multiple coexisting ions. Economic analysis also indicated that treating Sb mine flotation wastewater per ton may yield a net profit of $40.09. This research contributes to the advancement of an atomic H* enhanced electrochemical technology for high-valued heavy metal recovery from complex heavy metal-polluted wastewater.
研究领域:
环境科学
·
冶金工程
·
电化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）