APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Wenming Liu,Shenyou Yang,Qiuli Zhang,Tianyao He,Yiwei Luo,Jinxiong Tao,Daishe Wu,Honggen Peng
Herein, a series of nano-flower sheet-like alumina spheres (NF-Al 2 O 3 ) with rich unsaturated pentacoordinate Al 3+ sites stabilizing Ru-CeO x catalysts were designed and synthesized for catalytic total oxidation of one typical light alkanes (propane, C 3 H 8 ). The 90 % conversion temperature (T 90 ) and the apparent activation energy (Ea) of Ru-Ce 7 /NF-Al 2 O 3 modified by 7 wt.% of CeO 2 were as low as 207 °C and 56.7 kJ mol −1 , respectively. In addition, it also exhibited superior water, sulfur and carbon dioxide resistance and recycling performance. The excellent catalytic performance of propane total oxidation over Ru-CeO x /NF-Al 2 O 3 is mainly attributed to NF-Al 2 O 3 has rich unsaturated pentacoordinate Al 3+ sites can anchor the Ru-CeO x active species. The anchoring effect of Al 3+ penta on the metal active unit can effectively promote the dispersion of Ru-CeO x active species and stabilize the electronic valence state of Ru 0 . The degradation of C 3 H 8 over Ru-CeO x /NF-Al 2 O 3 conformed to the Mars-van-Krevelen mechanism through two different pathways as revealed by the in situ DRIFTS.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2021
·Vol. 93
·期 8
·1361-1369
·
IF 1.946
Shengkai Xu,Jiaxin Yang,Rafaat Hussein,Guangqing Liu,Bensheng Su
In this study, the performance of ofloxacin (OFX) degradation in synthetic wastewater using synthesized MnO x -CeO x /γ-Al 2 O 3 as a heterogeneous ozonation catalyst was evaluated. The removal rates of OFX and chemical oxygen demand (COD) during 15-day continuous-flow experiments were 98.2% and 76.7% on average, respectively. An ozone index (mgCOD/mgO 3 ) of 1.09 with a high ozone utilization efficiency of 91.39% was achieved. The pseudo-first-order rate constant of ofloxacin degradation reached 15.216 × 10 −2 min −1 , which was five times that (3.085 × 10 −2 min −1 ) without catalysts. The results of gas chromatography-mass spectrometry (GC-MS) demonstrated that a variety of small-molecule organics occurred in the final oxidation products, such as 4-hydroxyl-4-methyl-2-pentanone and 2-oxoadipic acid in addition to homologs of OFX. The results of this study suggested that hydroxyl radicals played critical roles in the degradation and mineralization of OFX via four main pathways: (a) electrophilic addition of nitrogen; (b) breakdown of carbon-carbon double bonds; (c) hydrolysis of ether rings; and (d) halodecarboxylation of carboxyl groups. The biodegradability (BOD 5 /COD) of OFX after catalytic ozonation reached 0.54. Practitioner points Ofloxacin wastewater was treated using catalytic ozonation in a 15-day continuous experiment with MnO x -CeO x /γ-Al 2 O 3 as a catalyst. The ozone index reached 1.09 mgCOD/mgO 3 during ozonation of ofloxacin. The presence of the catalyst increased the reaction rate constant by a factor of five. 4-hydroxy-4-methyl-2-pentanone was the primary ofloxacin oxidation product.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Nano
·
2021
·Vol. 8
·期 11
·3138-3152
·
IF 8.131
Weirui Chen,Hengxi He,Ruini Zou,Yidan Chen,Xukai Li,Jing Wang,Yiming Tang,Laisheng Li
In this study, CeOx with different exposed facets was prepared to investigate their potential effect on activating the peroxone reaction (H2O2/O3) and breaking through the restriction of solution pH on peroxone. By controlling the concentration of hydroxide, cube CeOx with a (100) facet, rod CeOx with a (110) facet and octahedron CeOx with a (111) facet were prepared by the hydrothermal precipitation method, and they all promoted heterogeneous peroxone for oxalic acid (OA) under acidic conditions. The catalytic activity of CeOx was highly related to their surface oxygen vacancies (OVs) and the interfacial electron transfer process. Both experiments and theoretical calculations showed that CeOx with different exposed facets activated peroxone in different ways and (111) CeOx possessed better activity than (100) or (110) CeOx. The low efficiencies of (100) and (110) CeOx were due to their inefficient use of H2O2 to reduce surface Ce4+ and their large energy gap to generate surface peroxide (OVs-OOH). (111) CeOx was stable with surface-adsorbed H2O2, and the rich electrons at OVs could be donated to H2O2 and generate OVs-OOH, which then triggered O3 decomposition into hydroxyl radical (˙OH) and superoxide radical (˙O2−). These electron migration processes depended on the electron-donating ability of the OVs rather than solution pH, therefore, still greater amounts of reactive species were generated under acidic conditions. The flexibility of the (111) CeOx/H2O2/O3 process was further investigated for removing 20 kinds of pharmaceuticals. The synergy effect of (111) CeOx/O3 and H2O2 varied with the structure of the pharmaceuticals.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Peng Wang,Hao Cui,Chengxin Wang
Although Pt-based alloy catalysts have been considered promising candidates for fuel cell applications, constructing highly efficient, multifunctional Pt-based catalysts that simultaneously boost the three key reactions (MOR, ORR and HOR) in proton exchange membrane fuel cells (PEMFCs) remains a huge challenge. Herein, PtMo-CeO x hybrids with interesting ultrathin and ultralong nanowire assemblies (NAs) structure are synthesized by a one-pot solvothermal method without templates. The PtMo-CeO x -NAs catalyst exhibits 5.2-fold, 6.9-fold and 2.4-fold higher mass activity than commercial Pt/C towards the MOR, ORR and HOR simultaneously and shows excellent durability and CO poisoning tolerance. Detailed experiments reveal that the enhancement should be due to strain and ligand effects. Most impressively, when PtMo-CeO x -NAs membrane electrode assemblies (MEAs) fabricated by a catalyst-coated method are used both as the anode and cathode in PEMFCs, the performance of fuel cells is dramatically boosted compared to those with Pt/C.
研究领域:
材料科学
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催化化学
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燃料电池研究
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2023
·Vol. 16
·期 21
·e202300754
·
IF 8.4
Jing Guo,Feng Li,Yuting Chu,Peng Zou,Chuang Li
Graphical The 10 % Ni@CeOx catalyst exhibits excellent catalytic efficiency in the reduction amination of levulinic acid to prepare 1,5-dimethyl-2-pyrrolidone. 1,5-dimethyl-2-pyrrolidone (MNMP), as a highly efficient green solvent, can be obtained from biomass-derived levulinic acid and its esters with 100 % conversion and 96.8 % yield over a 10 % Ni@CeOx catalyst at 140 °C, 2 MPa H 2 , 8 h, and with water as the solvent. Structure-property correlation investigations were performed with diverse characterization methods, including BET, XRD, XPS, TEM, HAADF-STEM, H 2 -TPR, NH 3 -TPD, CO 2 -TPD and FT-IR, and the results revealed that the excellent catalytic performance of the 10 % Ni@CeOx catalyst was mainly resulted from the strong interaction between Ni and CeOx, which formed more catalytic active sites and contributed to higher reductive amination efficiency. Besides, the 10 % Ni@CeOx catalyst had a chemisorption effect on LA. This was also the key to the excellent catalytic activity of the 10 % Ni@CeOx catalyst. The 10 % Ni@CeOx catalyst exhibited great stability throughout 6 reaction runs and excellent catalytic efficiency in the kilogram scale preparation of MNMP. This work provides a low-cost, efficient, and environmentally friendly heterogeneous catalytic system for the production of MNMP.
研究领域:
催化化学
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绿色化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF RARE EARTHS
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2022
·
IF 4.632
Ningyuan Wang,Xiaoqiang Wang,Yue Liu,Zhongbiao Wu
Traditional vanadium-based selective catalytic reduction (SCR) deNO x catalyst can hardly adapt to the gas conditions (much high NO 2 /NO x ratio at lower temperature) of the start-up and low loading periods for a gas turbine . Therefore, a W–Ti-CeO x catalyst with NO x storage and reduction (NSR) function was developed in this work for gas turbine exhaust NO x elimination. The experimental results reveal that W–Ti-CeO x catalyst exhibits high NO 2 adsorption capacity at relatively low temperature while that is quite low for V–W/TiO 2 . The abundant surface Ce 3+ species can be mainly responsible for its high adsorption ability owing to the reaction between NO 2 and Ce 3+ to form nitrate/nitrite species and NO. Meanwhile, the adsorption capacity of W–Ti-CeO x can easily regenerate at medium–high temperature and NH 3 -SCR reaction. Furthermore, W–Ti-CeO x also shows good NH 3 -SCR activity, which can fulfill the deNO x process at high temperature. The addition of W and Ti into ceria can enhance the surface acidity and redox ability, thereby increasing the SCR activity. This work proposes a novel storage-reduction strategy for NO x elimination throughout the operation of gas turbines.
研究领域:
环境工程
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催化
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Li Sun,Zhili Qiao,Yuan Zhi,Hua Zhang,Binlin Dou,Yuejin Shan,Weijia Huang
Bulk noble metal–semiconductor composites can be chosen as photocatalysts to carry out the flow degradation of 4-nitrophenol (4-NP) whereas their preparation is complex and uncontrollable. Here, bulk Au-Co-CoO x -CeO x @iron ball (Au/Co-CC@iron ball) is designed and prepared by a facile and controllable route without any toxic chemical. The bulk Au/Co-CC@iron ball shows excellent photocatalytic activity and reusability for the 4-NP degradation, which can be ascribed to the synergistic action of active components and foliated iron ball surface. Furthermore, the highly active Au/Co-CC@iron ball is used as packing material to construct a new-type of packed reactor, by which the flow degradation of 4-NP is successfully achieved. As-fabricated packed reactor and its tandem module exhibit superior photocatalytic performance for the flow degradation of 4-NP. Noteworthy, based on the tandem module with six reactors, the removal rate of 4-NP can reach up to 2750 µmol/h. Meanwhile, the reactor and its module display satisfactory operational stability and reusability in the flow degradation of 4-NP. Clearly, the provided route is effective for the preparation of bulk noble metal–semiconductor composites with exceptional performance, which can also be a prospective strategy to obtain bulk packing materials to serve for the flow degradation.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2024
·
IF 11.3
Yuanjie Xu,Jikang Yao,Hongqiao Lin,Qian Lv,Bo Liu,Lizhi Wu,Li Tan,Yihu Dai,Xupeng Zong,Yu Tang
Enhancing catalyst durability is a critical concern in the partial oxidation of methane (POM) to syngas since the reaction is operated at high temperatures (>600 °C). Alongside sintering and coke deposition, the deactivation of the supported Ni catalyst is often due to the in situ oxidation of active metallic nanoparticles into inactive cations during the POM reaction. Herein, a Ni/BN catalyst was developed by introducing functional CeOx as a promoter to stabilize the Ni sites. The optimized 4Ni/7.5Ce/BN catalyst, comprising 4 wt % Ni and 7.5 wt % Ce on BN, exhibits enhanced stability during continuous testing at 600 °C for 125 h without any deactivation, which is comparable to that of noble metal catalysts. Comprehensive investigations reveal that maintaining the metallic state of Ni under reaction atmosphere is crucial for the stability of the catalyst. The construction of CeOx on BN effectively inhibits migration and oxidation of the catalytically active Ni0 species.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Xiaofeng Wang,Chengcheng Zhang,Zuyi Zhang,Yaoming Gai,Qingbo Li
The interface site between metal and support possess unique electronic and morphological structure, providing distinct active centers for favorable reaction in catalytic conversion of biomass derivatives to valuable chemicals. In this study, a series of Cu-Co/CeO x catalysts were prepared for hydrogenolysis of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) via reduction of the corresponding layered double hydroxide precursors. The characterizations indicated the formation of CoCe-Vö interface (Vö denotes oxygen vacancy) and the effect of hydrogen spillover from Cu species to CoCe-Vö interface. Furthermore, the experiments and theoretical calculations verified that CoCe-Vö interface could activate the C O bond. The optimized catalyst showed a DMF yield of > 90% at 180 °C and 1.5 MPa H 2 with no deactivation in the cycling tests. This study reveals the interfacial effects of the nanocatalysts, including the oxygen vacancies and hydrogen spillover, on hydrogenolysis of HMF, which provided a simple and efficient approach for synthesis of high-performance non-noble metal nanocatalysts applied to the hydrogenolysis of various biomass derivatives.
研究领域:
催化化学
·
生物质转化
·
纳米材料科学
✓ 已验证
DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2021
·Vol. 15
·期 6
·1-10
·
IF 4.357
Wang Xinyu,Jin Ye,Chen Weirui,Zou Ruini,Xie Jinxin,Tang Yiming,Li Xukai,Li Laisheng
E-peroxone (EP) was one of the most attractive AOPs for removing refractory organic compounds from water, but the high energy consumption for in situ generating H 2 O 2 and its low reaction efficiency for activating O 3 under acidic conditions made the obstacles for its practical application. In this study, cerium oxide was loaded on the surface of graphite felt (GF) by the hydrothermal method to construct the efficient electrode (CeO x /GF) for mineralizing carbamazepine (CBZ) via EP process. CeO x /GF was an efficient cathode, which led to 69.4% TOC removal in CeO x /GF-EP process with current intensity of 10 mA in 60 min. Moreover, CeO x /GF had the flexible application in the pH range from 5.0 to 9.0, TOC removal had no obvious decline with decrease of pH. Comparative characterizations showed that CeO x could enhance surface hydrophilicity and reduce the charge-transfer resistance of GF. About 5.4 mg/L H 2 O 2 generated in CeO x /GF-EP process, which was 2.1 times as that in GF-EP process. The greater ozone utility was also found in CeO x /GF-EP process. More O 3 was activated into hydroxyl radicals, which accounted for the mineralization of CBZ. An interfacial electron transfer process was revealed, which involved the function of oxygen vacancies and Ce 3+ /Ce 4+ redox cycle. CeO x /GF had the good recycling property in fifth times’ use.
研究领域:
环境科学
·
水处理
·
电化学
·
催化
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2019
·Vol. 43
·期 8
·3823-3836
·
IF 3.343
Xiang Luo,Yu Hong,Honglei Zhang,Kaiqi Shi,Gang Yang,Tao Wu
Summary Steam reforming of ethanol (SRE) over non-noble metal catalysts is normally conducted at high temperature (>600°C) to thermodynamically favour the catalytic process and carbon deposition mitigation. However, high temperature inhibits water-gas shift reaction (WGSR) and therefore restrains the yield of H 2 and leads to the formation of an excessive amount of CO. The modification of non-noble metal catalyst to enhance WGSR is an attractive alternative. In this study, CeO x was firstly loaded onto a nano-scaled Ni x Mg y O matrix and subsequently used as the catalyst for hydrogen production via SRE. Morphology of the catalyst materials was characterized by using a series of technologies, while H 2 -temperature programmed reduction (H 2 -TPR), CO-temperature programmed deposition (CO-TPD), and X-ray photoelectron spectroscopy (XPS), were employed to study the surface nickel, ceria clusters, and their interactions. The catalytic activity and durability of the catalyst were studied in the temperature region of 500°C to 800°C. The CeO x -coated nano Ni x Mg y O matrix exhibited an outstanding hydrogen yield of 4.82 mol/mol ethanol under a high gas hourly space velocity (GHSV) of 200 000 hour −1 . It is found that the unique Ni 0 -CeO x structure facilitates the adsorption of CO on the surface and therefore promotes the effective hydrogen production via WGSR. Moreover, this modified Ni x Mg y O matrix was found to be a more robust and anticoking nanocatalyst because of reversible switch between Ce 4+ and Ce 3+ .
研究领域:
催化化学
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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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Jia-Yun Wang,He-Nan Shang,Di Liu,Si-Jia Li,Ya-Xuan Bai,Yu-Bo Liu,Jin-Sheng Liang
Formic acid (HCOOH, FA), a common liquid hydrogen storage material, has attracted tremendous research interest. However, the development of efficient, low-cost and high-stable heterogeneous catalyst for selective dehydrogenation of FA remains a major challenge. In this paper, a simple co-reduction method is proposed to synthesize nitrogen-phosphorus co-functionalized rGO (NPG) supported ultrafine NiCoPd-CeO x nanoparticles (NPs) with a mean size of 1.2 nm. Remarkably, the as-prepared Ni 0.2 Co 0.2 Pd 0.6 -CeO x /NPG shows outstanding catalytic activity for FA dehydrogenation, affording a high TOF value of 6506.8 mol H 2 mol Pd −1 h −1 at 303 K and a low activation energy of 17.7 kJ mol −1 , which is better than most of the reported heterogeneous catalysts, and can be ascribed to the combined effect of well-dispersed ultrafine NiCoPd-CeO x NPs, modified Pd electronic structure, and abundant active sites. The reaction mechanism of dehydrogenation of FA is also discussed. Furthermore, the optimized Ni 0.2 Co 0.2 Pd 0.6 -CeO x /NPG shows excellent stability over 10 th run with 100% conversion and 100% H 2 selectivity, which may provide more possibilities for practical application of FA system on fuel cells.
研究领域:
催化
·
材料科学
·
能源存储
·
纳米技术
✓ 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）