CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Ting Su,Yunhe Gong,Xue Cui,Xinhong Wang,Yanan Zhang,Hongbin Yu
Oxidizing ammonia to nitrogen is a challenge in wastewater treatment. For this challenge ammonia oxidation via chlorine oxide radicals has been proved to be a potential method. In this study, a space-confined photoanode was designed and prepared by loading RuO 2 nanoparticles on TiO 2 /WO 3 nanowires for in situ enhancing the generation of chlorine oxide radical. Scanning electron microscopy characterization confirmed that RuO 2 nanoparticles were uniformly deposited on TiO 2 /WO 3 nanowires. The generation of chlorine oxide radical was markedly boosted, and its steady-state concentration reached 2.76 × 10 −12 M. This value was 3 times that of the traditional bifacial electrode (a type of electrode that has been widely used for chlorine oxide radical-related research). As a result, ammonia oxidation was greatly enhanced. In 90 min, 31.9 mg/L ammonia nitrogen could be degraded, yet only 0.94 mg/L nitrate was accumulated. In addition, the space-confined photoanode exhibited good performance for real wastewater treatment, and 41.0 mg/L ammonia nitrogen could be oxidized in 135 min. During photoelectrocatalysis, a synergistic index (47.7 %) was obtained. Besides the synergistic effect between photocatalysis and electrocatalysis, the unique morphology and structural design (TiO 2 /WO 3 and RuO 2 were mainly responsible to hydroxyl radical generation and free chlorine production, respectively) also synergistically promoted the generation of chlorine oxide radical, thereby improving ammonia oxidation. The mechanism for ammonia oxidation via chlorine oxide radicals over the space-confined photoanode was proposed based on experimental results and theoretical calculations.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 4
·781
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IF 3.9
He Sun,Juping Zhang,Kongzhai Li,Hua Wang,Xing Zhu
HighlightsWhat are the main findings?A styrene yield of 91.4% was found for 10% k/CeO2at 500 °C and CO2-O2mixed atmosphere. The excellent catalytic performance of 10% k/CeO2is attributed to the alkali metal oxide modified cerium oxide and carbon dioxide induced oxygen vacancies to promote the dehydrogenation of ethylbenzene.What is the implication of the main finding?The proposed ODH strategy by using oxygen vacancies enriched catalysts offers an important insight into the efficient dehydrogenation of ethylbenzene at mild conditions.AbstractOxidative dehydrogenation (ODH) is an alternative for styrene (ST) production compared to the direct dehydrogenation process. However, ODH with O2or CO2suffers from either over-oxidation or endothermic property/low ethylbenzene conversion. Herein, we proposed an ODH process with a CO2-O2mixture atmosphere for the efficient conversion of ethylbenzene (EB) into styrene. A thermoneutral ODH is possible by the rationalizing of CO2/O2molar ratios from 0.65 to 0.66 in the temperature range of 300 to 650 °C. K modification is favorable for ethylbenzene dehydrogenation, and 10%K/CeO2achieved the highest ethylbenzene dehydrogenation activity due to the enhanced oxygen mobility and CO2adsorbability. The catalyst achieved 90.8% ethylbenzene conversion and 97.5% styrene selectivity under optimized conditions of CO2-4O2oxidation atmosphere, a temperature of 500 °C, and a space velocity of 5.0 h−1. It exhibited excellent catalytic and structural stability during a 50 h long-term test. CO2induces oxygen vacancies in ceria and promotes oxygen exchange between gaseous oxygen and ceria. The ethylbenzene dehydrogenation in CO2-O2follows a Mars-van Krevelen (MvK) reaction mechanism via Ce3+/Ce4+redox pairs. The proposed ODH strategy by using oxygen vacancies enriched catalysts offers an important insight into the efficient dehydrogenation of ethylbenzene at mild conditions.Keywords:ethylbenzene;oxidative dehydrogenation;ceria;CO2
研究领域:
化学工程
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催化科学
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DOI
高影响因子
CATALYSIS LETTERS
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2017
·Vol. 148
·期 1
·181-193
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IF 2.799
Lin Jin,Guo Yafei,Chen Xiao,Li Changhai,Lu Shouxiang,Liew Kim Meow
Abstract Nanostructured CeO 2 supported CuO–MnO 2 (CuMn/Ce) catalysts were synthesized by wet co-impregnation method and compared with CuO/CeO 2 and MnO 2 /CeO 2 catalysts on CO oxidation. The former shows significantly higher catalytic activity toward CO oxidation than the bimetallic oxides catalysts with minimum T 50 . Dual synergistic effects in the interfaces of CuO–MnO 2 and CuO–CeO 2 shall be responsible for the higher oxidation performance of CuMn/Ce catalyst. As Cu/Mn mass ratio varies from 1/0.2 to 1/9, CO oxidation activities of the catalysts present unimodal distribution, and the catalyst with Cu/Mn = 1/1 shows the highest performance (T 50 = 45.8 °C; Ea = 24.11 kJ mol −1 ). Cu acts as CO dissociative adsorption sites, and Mn–Ce supplies activated O species from gas molecule and lattice oxygen, which are both indispensable for improving utilization efficiency of the reactants in the dual redox processes. The catalytic performance of catalyst is also vitally correlated with calcination temperature (160–320 °C). The optimum calcination temperature of CuMn/Ce catalyst is 320 °C. Catalyst characterization results indicate that the pretreatment at 320 °C is decent to obtain desired metal oxides along with fine texture properties. Graphical Abstract
研究领域:
催化化学
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材料科学
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环境化学
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Qinghe Liu,Sen Wang,Fei Han,Shupei Lv,Zairong Yan,Yunfei Xi,Jing Ouyang
Highly efficient three-dimensional (3D) kaolinite/MnO2–CuO (KM@CuO–NO3) catalysts were synthesized by a mild biomimetic strategy. Kaolinite flakes were uniformly wrapped by ultrathin tremelliform MnO2 nanosheets with thicknesses of around 1.0–1.5 nm. Si–O and Al–O groups in kaolinite hosted MnO2 nanosheets to generate a robust composite structure. The ultrathin MnO2 lamellar structure exhibited excellent stability even after calcination above 350 °C. Kaolinite/MnO2 exhibited abundant edges, sharp corners, and interconnected diffusion channels, which are superior to the common stacked structure. Open channels guaranteed fast transportation and migration of CO and O2 during CO oxidation. The synthesized KM@CuO–NO3 achieved a 90% CO conversion efficiency at a relatively low temperature (110 °C). Furthermore, the abundant oxygen vacancies on KM@CuO-NO3 assisted the adsorption and activation of oxygen species and thus enhanced the oxygen mobility and reactivity in the catalytic process. The mechanism results suggest that CuO introduced to the catalyst not only acted as CO active sites but also weakened the Mn–O bond, subsequently improved the mobilities of the oxygen species, which was found to contribute to its high activity for CO oxidation. This study provides new conceptual insights into rationally regulating structural assembly between transition metal oxides and natural minerals for high-performance catalysis reactions.
研究领域:
材料科学
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催化化学
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DOI
PubMed
高影响因子
RSC Advances
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2017
·Vol. 7
·期 75
·47435-47447
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IF 3.108
Donglin He,Huiping Zhang,Ying Yan
CuO over ZSM-5 zeolite membrane was prepared by chemical vapor deposition (CVD) for catalytic wet peroxide oxidation (CWPO) of phenol in a fixed bed reactor. Firstly, Cu-ZSM-5/PSSFs catalysts with Cu loading of 2 wt%, 4 wt% and 6 wt% were prepared and characterized by XRD, XPS, SEM, EDS, N2 adsorption–desorption and TPR (H2), respectively. Compared with CuO deposited directly onto PSSFs, the CuO supported on ZSM-5/PSSFs tended to be more regular with smaller crystal size. Then, several parameters affecting H2O2 consumption and phenol oxidation such as reaction temperature, Cu loading, and different supports were investigated in the CWPO of phenol with a high concentration (1 g L−1 phenol and 5.1 g L−1 H2O2). Experimental results revealed that Cu-ZSM-5/PSSFs (6%) showed better activity for the oxidation of phenol than Cu-ZSM-5/PSSFs catalysts with lower Cu loading and CuO/PSSFs with same theoretical loading. A complete reduction of phenol and a high TOC removal around 60% had been achieved over Cu-ZSM-5/PSSFs (6%) at the temperature of 80 °C, feed flow rate of 2 mL min−1 and catalyst bed height of 2 cm. Finally, the possible oxidation pathway of phenol was studied based on the by-products detected by high-performance liquid chromatography (HPLC).
研究领域:
环境科学
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化学工程
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Yi Fang,Shoubing Chai,Zhiwei Chu,Zirui He,Yingjie Li
In the calcium looping CO 2 capture process, using CO in the flue gas to reduce NO at a high molar ratio of CO to NO (e.g., above 10:1) can achieve efficient removal of NO. However, the lots of unreacted CO causes secondary pollution. In this study, a novel Cu/Ce co-modified CaO was proposed for cyclic CO 2 capture and the catalytic NO reduction at a low CO:NO molar ratio (e.g., 2:1). The experimental findings indicate that Cu/Ce modification improves the performance of CaO in both catalytic NO reduction and carbonation. The Cu/Ce co-modified CaO contained the optimal Cu/Ce/Ca molar ratio of 1:5:100 possesses both NO removal and CO conversion efficiencies of above 99 %, along with CO 2 removal efficiency exceeding 88%. Microscopic analysis determines that the electron transfer between Cu and Ce facilitates the conversion of lattice oxygen into surface oxygen, mitigating the competition between CO 2 and CO for surface oxygen. Furthermore, density functional theory calculations demonstrate that CO/NO/CO 2 exhibits non-competitive adsorption behavior on Cu/Ce co-modified CaO. Consequently, Cu/Ce-modified CaO possesses superior catalysis for efficient NO reduction by CO at low CO:NO molar ratio in calcium looping process.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2023
·Vol. 47
·期 39
·18476-18484
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IF 3.3
Bin Liu,Haoliang Ruan,Chengyi Li,Jie Yao,Bei Wei,Lei Wang,Shurong Ban,Jun Xie
In this work, InCex nanoparticles with different In–Ce ratios were synthesized by a simple co-precipitation method and InCex nanoparticles could be used as a mimic of peroxidase to catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2 and produce the typical blue ox TMB. In addition, the prepared InCex nanoparticles showed excellent peroxidase-like catalytic properties compared with pure CeO2 and pure In2O3. InCe0.1 exhibited the best peroxidase-like activity, which was mainly attributed to the indium–cerium synergy, which accelerated the TMB and H2O2 electron transfer rate between them. Based on the above findings, a facile and sensitive H2O2 detection system with a sensitive response range of 10–100 μM and a detection limit of 5 μM for H2O2 was successfully proposed. This work synthesizes nanomaterials with peroxidase-like activity by modifying In2O3 through a simple co-precipitation method and offers new insights into the search for novel peroxidase mimics.
研究领域:
生物化学
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材料科学
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分析化学
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DOI
高影响因子
ENERGY
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2017
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IF 4.52
J. Yan,C.Y. Zhao,Z.H. Pan
Cyclic stability is a key factor in the design of thermochemical heat storage systems . Because carbon dioxide (CO 2 ) may react with heat storage materials and lead to a decrease in energy storage efficiency, the effect of CO 2 on Ca(OH) 2 /CaO and Mg(OH) 2 /MgO systems is investigated in this study. The experimental results show that CO 2 reacts with CaO in the water vapor that appears during the heat release process. Therefore, in the design of Ca(OH) 2 /CaO systems, CO 2 should be cleared from the system. The results from Mg(OH) 2 /MgO systems show that CO 2 only slightly reacts with MgO and Mg(OH) 2 during heat storage and release processes. This study indicates that carbonic acid (H 2 CO 3 ) could easily react with CaO/Ca(OH) 2 to form CaCO 3 during heat release processes. Generally, the remaining CO 2 reduces the reversibility of Ca(OH) 2 /CaO systems but has only a slight influence on Mg(OH) 2 /MgO systems. In addition, the experimental results show that carbonate shell does not exist in rehydration for both of the CaO/MgO samples, but the influence of CO 2 on the entire process increases after each cycle.
研究领域:
材料科学
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能源工程
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DOI
高影响因子
ACS Applied Nano Materials
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2021
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IF 5.097
Yuanjie Xiong,Xiang Liu,Tian Cheng Zhang,Shaojun Yuan
The conversion of As(III) to As(V) in groundwater is an urgent issue, owing to the higher mobility, stronger toxicity, and weaker binding ability of As(III). In this work, the electrocatalytic oxidation of As(III) was efficiently achieved with a facile and environmentally benign method by using hierarchical MnO2-deposited TiO2 nanotube arrays (MnO2/TNAs) as the anode. The electrocatalytic oxidation performance of the as-fabricated MnO2/TNA-coated anode was systematically investigated. The results exhibited that such as-fabricated MnO2/TNAs had a high oxidation efficiency of 90% at a low concentration of As(III) (1 mg L–1). Furthermore, the reaction mechanism was systematically studied by electron spin resonance and free radical capture experiments. The oxidation of As(III) was accomplished via both direct oxidation on the anode surface and indirect oxidation of the reactive oxygen species. The highly efficient TNA-based anode offers a potentially promising advanced material for electrochemical oxidation of trace As(III) in the practical field.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Ning Kang,Zhiqiang Zhao,Xiaoyang Yu,Jin Lin,Shouxiang Lu
The application of ceria-supported catalysts as promising catalysts for air pollutant abatement via heterogeneous catalytic processes is still a challenge. Phosphorus (P) is a potential threat to catalyst deactivation but has not been sufficiently explored. Herein, a systematic study reveals the poisoning behaviors of P on Cu-Mn bimetallic oxides supported by ceria (Cu-Mn/CeO 2 ) as a typical case in CO oxidation and provides new insights into the deactivation mechanism. The P impregnation decreases the surface area of Cu-Mn/CeO 2 and leads to the emergence of a new sheet morphology. The interactions between P and catalyst components (support and active species) result in the generation of dominant P species of PO 4 3− and PO 3 − . The P addition also weakens the oxygen storage capacity of ceria and decreases the proportions of low-valent Cu and Mn, hindering electron transfers among metals. Furthermore, the reducibility and the adsorption and activation of O 2 are limited in P-loaded Cu-Mn/CeO 2 catalysts as found in H 2 -TPR and O 2 -TPD when increasing the P concentration. In situ DRIFTS experiments demonstrate that the inhibition of the formation and transformation of active intermediates, namely carbonyls and carbonates, is responsible for the poisoning behaviors of P in the pathway of CO oxidation over Cu-Mn/CeO 2 catalyst.
研究领域:
环境科学
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催化化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Archer Bright,Wuyi Zhang,Kaisong Xiang,Hao Chen,Hui Liu,Jun Wu
CuO-CeO 2 composite catalyst for low temperature CO oxidation was fabricated via an impregnation method. The prepared composite CuO-CeO 2 achieved 50 % and 100 % conversion at approximately ∼ 70℃ and ∼ 110℃ (denoted as T 50 and T 100 ), respectively. The enhanced catalytic activities were attributed to the formation of abundant CuO/CeO 2 heterostructures, which increased the concentration of oxygen vacancies in their lattices. In addition, the pore structure of the CuO-CeO 2 composite has also been optimized during the impregnation synthesis process. Compared with bare CeO 2 , which only possesses micropores, CuO-CeO 2 forms more mesopores on its surface, which assists in reducing the deposition rate of sulfate species on the surface. The SO 2 tolerance of the catalyst and hence its stability towards practical industrial flue gas treatment is significantly promoted. Furthermore, Density Functional Theory (DFT) was also performed to explore the mechanism of CO oxidation on the CuO-CeO 2 . It was found that the oxygen vacancy can be easily formed on the CuO/CeO 2 heterointerfaces; the adsorption energy (ΔG) of CO was therefore decreased to 0.15 eV, much lower than that of bare CeO 2 (0.53 eV). Besides, the center of f electrons of Ce in CeO 2 rises from −0.55 eV to – 1.71 eV by introducing CuO, suggesting that the f electrons in Ce become more active, which is beneficial for CO to adsorb.
研究领域:
催化化学
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环境化学
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材料科学
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表面化学
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工业催化
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DOI
高影响因子
JOURNAL OF PHASE EQUILIBRIA AND DIFFUSION
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2017
·Vol. 38
·期 1
·30-36
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IF 0.938
Sun W. Z.,Cheng J. G.,Huang Z. K.,Jiang Y.,Wu L. E.,Liu L. M.
The present work determined the phase relations in Si-Al-M-O-C (M = Zr, Mg) systems, involving SiC-Al 2 O 3 -ZrO 2 , SiC-Al 2 O 3 -MgO, SiC-SiO 2 -Al 2 O 3 -ZrO 2 and SiC-SiO 2 -Al 2 O 3 -MgO systems by XRD phase analyses of the solid-state reacted samples from powder mixtures of SiC, Al 2 O 3 , ZrO 2 , MgO and SiO 2 . Within these systems, SiC was respectively compatible with other neighboring phases, forming a set of four-phase compatibility tetrahedrons. The subsolidus phase diagrams of the SiC-SiO 2 -Al 2 O 3 -ZrO 2 and SiC-SiO 2 -Al 2 O 3 -MgO quaternary systems were presented.
研究领域:
材料科学
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陶瓷学
✓ 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）