Environmental Science-Nano
·
2025
·
IF 5.1
Junjie Yang,Jun Xie,Junxian Qin,Jin Shang,Hiromi Yamashita,Daiqi Ye,Yun Hu
To address the critical challenges in photocatalytic CO2 reduction systems, including rapid recombination of photogenerated electron–hole pairs, indiscriminate product distribution, and oxidative degradation of liquid-phase intermediates, we designed a ZIF-8-derived Ni–Cu bimetallic modified TiO2 (NiCu-GC-TiO2) photocatalyst for synergistic formate synthesis from CO2 and ammonia nitrogen wastewater The research results indicate that Ni–Cu forms a highly dispersed interface through N bridges, significantly enhancing charge separation efficiency. In the NH3-N system at pH = 10, the formate yield reached 116.2 μmol L−1 (99.4% selectivity), which was 9.4 times higher than that of TiO2. Ammonia nitrogen serves as an oxidative substrate that accelerates hole consumption while inhibiting formate oxidation. Isotope experiments confirmed that formate protons originate entirely from ammonia nitrogen, and the protons released from ammonia nitrogen oxidation drive the directed conversion of CO2 to formate. The system can directly utilize HCO3− as a carbon source, compatible with industrial carbon capture processes. Cycling tests and flow-phase experiments demonstrated excellent material stability and practical applicability. This research provides a novel strategy for synergistic mechanisms between photocatalytic CO2 reduction and wastewater treatment, which contributes to both environmental sustainability and energy utilization.
研究领域:
环境科学
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材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Hengjun Gai,Xiaofeng Liu,Bingxiao Feng,Chaojie Gai,Tingting Huang,Meng Xiao,Hongbing Song
Ammonia nitrogen wastewater is the most abundant and widely distributed wastewater. In this work, a highly dispersed heterogeneous metal catalyst Ru@TiO 2 was successfully fabricated by a one-pot method for the catalytic wet air oxidation (CWAO) of ammonia. These catalysts were characterized by different techniques, indicating that Ru clusters were dispersed uniformly on the TiO 2 surface, and some Ru atoms were embedded in the TiO 2 framework. This structure can afford excellent catalytic performance, such as 0.5%Ru@TiO 2 catalyst offers a 95.5% conversion under the condition of 2 MPa at 190 °C in 6 h without adding alkali. Ammonia concentration can be reduced from 200 ppm to less than 10 ppm to meet emission standards. And the selectivity of ammonia oxidation products can be adjusted and controlled according to the reaction conditions. Besides, the kinetics and mechanism of CWAO of ammonia were studied, which provided a theoretical basis for its industrial application.
研究领域:
环境科学
·
催化化学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2023
·
IF 7
Bingxiao Feng,Junxiu Xue,Donglin Yang,Hongbing Song,Meng Xiao,Tingting Huang,Quanhong Zhu,Hengjun Gai
Deep treatment is an important tool to solve the environmental pollution of ammonia-containing wastewater. Considering the stability and economy of industrial application, we propose a simple and economical synthesis strategy. The procedure is based on the carbonization of citrate at elevated temperatures to synthesize high specific surface area and pore-rich carbon nanoflowers , and carbon nanoflower-loaded Pt catalysts were constructed for the catalytic wet air oxidation (CWAO) of ammonia-containing wastewater. The results showed that the synergistic effect of Pt, edge carbon and carboxyl groups led to the increase of CWAO activity. During the reaction, Pt activated NH 3 to put it in a high-energy state, and there was a positive synergistic effect between the oxygen-containing functional groups (carboxyl groups) on the surface of the porous carbon nanoflowers and the edge carbon exposed at the adjacent defect sites, which promoted the activation of O 2 and the generation of reactive oxygen species . At 200 °C, the Pt 1 /PC catalysts showed high activity and hydrothermal stability for CWAO of NH 3 . The conversion of NH 3 was 98.24 % within 4 h, and the selectivity of N 2 was 100 %. The total nitrogen (TN) was reduced to below 15 mg‧L −1 , which meets the Chinese emission standard for TN in petrochemical industry . Therefore, the novel catalyst proposed in this study effectively solved the problems of complicated catalyst synthesis steps and poor hydrothermal stability in ammonia CWAO studies. The catalyst has potential industrial applications for CWAO of ammonia-containing wastewater.
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
ENVIRONMENTAL TECHNOLOGY
·
2022
·
IF 3.475
Zhen-xing Yang,Wen-yu Xie,Fang-fang Ye,De-hao Li
Electro-catalytic technology is a promising approach for wastewater treatment, owing to its easy operation, minimal generation of secondary pollution, small foot-print and rapid start-up. In this work, the chlorine evolution potential of the Pd-Sn modified ruthenium(Ru)-iridium(Ir) electrode was investigated for the electro-catalytic treatment of high chlorine ammonia-nitrogen wastewater. The effect of reaction conditions on the removal of ammonia-nitrogen, kinetics and apparent activation energy of ammonia-nitrogen removal were studied. The possible denitrification process of high chlorine ammonia-nitrogen wastewater was discussed. The results indicated that the chlorine evolution potential of the Pd-Sn modified Ru-Ir electrode was 1.0956 V(vs. SCE). The electro-catalytic treatment of high chlorine ammonia-nitrogen conformed to zero-order kinetic law, and the apparent activation energy of removal process was 14.089 kJ/mol. With a current was 0.5 A, the removal efficiency of ammonia-nitrogen could achieve 100% at a reaction time of 40 min. Indirect oxidation played an essential role in the electro-catalytic ammonia-nitrogen removal using the Pd-Sn modified Ru-Ir electrode. This paper demonstrated that the electro-catalytic technology was a promising approach for efficiently treating the high chlorine ammonia-nitrogen wastewater.
研究领域:
环境工程
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废水处理
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电化学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 11
·15337-15346
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IF 5.19
Yang Zhen-xing,Shang Jie,Yan Guang-xu,Wang Yu-xian,Guo Shao-hui
In this paper, Pd-Sn modified Ru-Ir electrode was prepared by thermal oxidation method, and the effects of doping amount of Pd-Sn and synthesis conditions on Pd-Sn modified Ru-Ir electrode performance were studied. Linear sweep voltammetry(LSV), cyclic voltammetry(CV), and the Tafel curve were used to study the electrochemical performance of the Pd-Sn modified Ru-Ir electrode materials. The effects of the doping amount of Pd-Sn on the microstructure and valence states of Pd-Sn modified Ru-Ir electrode materials were investigated by SEM, TEM, XRD, and XPS. When the mass of Pd-Sn accounted for 1.5% of the total mass of the elements, the molar ratio of Ru-Ir was 2:1, and the molar ratio of Pd-Sn was 3:1; the LSV, CV, and the Tafel curves indicated that Pd-Sn modified Ru-Ir electrode had the lowest chlorine evolution potential (1.0640 V vs. SCE), the best CV curve coincidence, and the smallest corrosion current density (6.5 × 10 −4 A/cm 2 ), showing the best chlorine evolution performance, the best durability, and corrosion resistance; the characterization of SEM, TEM, XRD, and XPS showed that Pd-Sn was successfully doped into Ru-Ir electrode materials; the crystallinity of Pd-Sn modified Ru-Ir electrode was the highest, and the binding energy was the lowest, but the crystal form of Ru-Ir solid solution did not have changed. The optimal synthesis conditions of Pd-Sn modified Ru-Ir electrode material were as follows: Pd-Sn molar ratio was 3:1, calcination temperature was 500 ℃, calcination time was 4 h, and water was used as solvent. Pd-Sn modified Ru-Ir electrode can efficiently treat high chlorine ammonia–nitrogen wastewater, when the reaction volume was 200 mL, the initial concentration of NH 3 -N was 100 mg/L, the concentration of chloride ion was 5000 mg/L, the current was 0.75 A, and the reaction time was 40 min; the removal rate of ammonia nitrogen can reach 100%. Responsible editor: Weiming Zhang.
研究领域:
环境科学
·
电化学
·
材料科学
·
废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）