Catalysts
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2021
·Vol. 11
·期 10
·1187
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IF 4.146
Qiuyue Zhou,Zhi-Qiang Wang,Wei Hong,Baohui Lou,Shihui Zou
Oxidative dehydrogenation of KA-oil (a mixture of cyclohexanone and cyclohexanol) is an economically attractive process to produce cyclohexanone because it provides a chance to avoid the energy-intensive alcohol-ketone separation process. The application of this process, however, is hampered by the low cyclohexanone selectivity which results from the competitive adsorption of cyclohexanol and cyclohexanone on the catalyst surface. Herein, by engineering Pt-Bi2O3interface to tune the geometric and electronic structure of Pt, we successfully weaken the cyclohexanone adsorption without compromising the oxidation of cyclohexanol. As a result, Bi2O3-Pt/SiO2with Bi-to-Pd ratio of 0.2 exhibits a 5 times higher cyclohexanone selectivity than Pt/SiO2at the same conversion of KA oil. Long term test suggests that the Pt-Bi2O3interface is stable in the oxidative dehydrogenation of KA-oil.Keywords:KA-oil;oxidative dehydrogenation;bismuth;Pt;electronic effect
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
ACS Sustainable Chemistry & Engineering
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2024
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IF 7.1
Jie Chen,Yi Shen
Selective oxidative cleavage of C(OH)–C or C(O)–C bonds in cyclohexanol and cyclohexanone (KA oil) to produce adipic acid (AA), a monomer for the synthesis of nylon-66, is of significant importance for the petrochemical industry. Herein, we report an electrochemical method to improve the efficiency for upgrading KA oil into AA. Free-standing electrodes consisting of hydroxides (Ni(OH)2 and Mn-doped Ni(OH)2) supported by carbon paper were fabricated via an in situ electrodeposition process and further examined for KA oil conversion. The morphology and structures of the samples were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. The electrochemical performance of the samples was studied by cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy. The products of KA oil oxidation were analyzed by high-performance liquid chromatography. The introduction of manganese into nickel hydroxides enhanced the catalytic performance in terms of activity and product selectivity. Specifically, the optimal sample exhibited a current density of 50 mA mg–1 and selectivity of 46.8%, which are superior to those of pure nickel hydroxides. Such enhancement was attributed to the electronic interaction of manganese with nickel hydroxides, thereby modifying the adsorption of the substrates. Interestingly, the introduction of Mn into nickel hydroxides had negligible effects in the oxygen evolution reaction. The effects of critical parameters including substrate composition, reaction temperatures, KOH concentrations, and electrolysis time on the conversion of KA oil were investigated.
研究领域:
材料科学
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电化学
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催化反应
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DOI
高影响因子
JOURNAL OF CATALYSIS
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2025
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IF 6.5
Jue Wang,Jinyi Yang,Siyu Zeng,Huitao Liu,Fei Li,Haijiao Xie,Senpei Tang,Zaihui Fu,Youji Li
The highly selective synthesis of KA oil (cyclohexanol and cyclohexanone) from the oxidation of cyclohexane (CHA) with O 2 under mild conditions is still a very important and challenging research topic. This paper discloses that the hybrid (DTCN) is easily prepared by inducing carbon nitride (CN) in the synthesis of decatungstate (DT) and is found to be efficiently photo-catalyst for the above selective oxidation in acetonitrile. After illumination (LED of 405 nm) for 2 h, the best DTCN-0.5 can achieve 41.03 % CHA conversion and greater than 95 % KA oil selectivity with an apparent quantum efficiency of 25.52 %, which is much superior to the pure DT (12.46 % CHA conversion). Also, it is active for the selective oxidation of other substrates containing inert C(sp 3 )-H bonds. A series of characterizations, free radical trapping and isotope tracing tests as well as DFT calculations support that the doped CN can construct a built-in electric field with DT to accelerate the separation of the photo-generated charge, thus hoisting the photo-excited quantum efficiency of DT. Furthermore, it also plays a key role in converting O 2 into superoxide (•O 2 – ) radical as the active oxygen donor. Additionally, the doped CN also contributes to the limited participation of water as a weak oxygen donor in the selective oxidation of CHA to cyclohexanol. It is hoped that this work will be informative for advancing the key technology of selective oxidation of saturated hydrocarbons under mild conditions.
研究领域:
化学工程
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材料科学
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环境科学
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DOI
高影响因子
ACS Catalysis
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2013
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IF 5.265
Wen-Juan Zhou,Raphael Wischert,Kai Xue,Yu-Ting Zheng,Belén Albela,Laurent Bonneviot,Jean-Marc Clacens,Floryan De Campo,Marc Pera-Titus,Peng Wu
Various types of Ti-containing zeolites, i.e., Ti-MWW, TS-1, Ti-MOR, and Ti-BEA, have been evaluated as candidates for the liquid-phase oxidation of cyclohexane using t-butyl hydroperoxide (TBHP, 7–8 wt %) as model oxidant. Ti-MWW zeolite displayed the highest activity for cyclohexanol and cyclohexanone (KA oil) with an overall selectivity higher than 90% at 80 °C, making this catalyst a candidate of choice for industrial KA oil production by deperoxidation of cyclohexyl hydroperoxide. The effect of the reaction temperature, reaction time, catalyst amount, and catalyst stability on Ti-MWW was surveyed in detail. The Ti-MWW catalyst showed a stable performance and could be recycled at least four times without detectable Ti leaching and loss of structural stability. The active sites for cyclohexane oxidation appeared to be located near external 12-ring cups in the Ti-MWW framework as suggested by a series of position-selective poisoning tests with tripropyl- and triphenylamine, impelling cyclohexane diffusion within the internal 10-ring channels. EPR experiments supported by DFT calculations suggested the coexistence of both Ti(IV)-OO• (peroxyl) and Ti(IV)-O• (oxyl) species generated through bimolecular pathways, implying simultaneously (SiO)3Ti(OOtBu) species and tBuOOH. The catalytic activity was strongly inhibited in the presence of alkenes, leading to the preferential formation of the epoxidation product with no detectable formation of radicals. Notably, this is the first time that oxyl species have been detected particularly with the help of DFT calculations. Predicted differences of g tensors between peroxyl and oxyl species at various hydration levels in the presence of cyclohexane were consistent with the EPR spectra.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2025
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IF 3.7
Shuang Wei,Yingwei Li,Longlong Wang,Kexin Li,Bin He,Ruirui Zhang,Ruixia Liu
Nanostructured ceria has attracted much attention in the field of redox catalysts due to the numerous active sites with excellent redox ability. Based on the acidic medium etching strategy, we constructed the strong binding centers (hydroxyl sites and strong acid sites) on the surfaces of nanostructured ceria, which regulate the adsorption process of KA-Oil (the mixture of cyclohexanol and cyclohexanone) and to promote high KA-Oil selectivity in cyclohexane oxidation. The three CeO 2 (nanocube, nanorod and nanopolyhedron) with different exposed crystal planes were treated by acid etching to change the surface sites and catalytic properties. The transition behavior of surface sites during etching was revealed, abundant strong binding centers were proved to be constructed successfully. And especially for the nanorod treated by acid (Acid@CeO 2 -NR) with the strongest response for sulfuric acid etching, the strong adsorption of cyclohexanone by strong binding centers was confirmed based on the in-situ DRIFTs. The sulfuric acid etching strategy to enhance the selective oxidation of cyclohexane based on the construction of strong binding centers was proved to be feasible and effective, Acid@CeO 2 -NR with strongest etching response achieved the dramatic promotion of KA-Oil selectivity from 64.1% to 92.3%.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
Molecular Catalysis
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2020
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IF 3.687
Yepeng Xiao,Jincheng Liu,Hui Wang,Chong Yang,Huicheng Cheng,Yiqiang Deng,Lihua Cheng,Yanxiong Fang
Designing high-performance catalyst for the oxidation of cyclohexane (CyH) into value-added products like cyclohexanol and cyclohexanone (the mixture called KA oil) is of paramount significance in chemical industry. Herein, the catalytic activity of graphene oxide coupled with Ag and Fe 3 O 4 nanopaticles composites (GO-Ag&Fe 3 O 4 NPs) was investigated to understand the synergistic effect between Ag and Fe 3 O 4 NPs in photothermal oxidation of CyH. The comparative experiments between thermal and photothermal catalysis indicated that: (a) Conversion efficiency was facilitated by temperature rise, but less than 50 % of selectivity to KA oil was obtained at high temperature (140 °C); (b) Higher selectivity and milder condition were achieved by photothermal catalysis comparing to that of the thermal catalysis; (c) Ag NPs played more important role in photocatalysis, while thermocatalysis was intensified by Fe 3 O 4 NPs. Using 1.5 MPa of dry air as oxidant, 6.6 % of CyH conversion with over 98 % of selectivity was gained by GO-Ag&Fe 3 O 4 NPs. Additionally, no obvious decline in catalytic efficiency was observed after 5 cycles. The concept of photothermal cooperation for CyH oxidation over GO-Ag&Fe 3 O 4 NPs may provide a new approach for the partial oxidation of saturated C H and the design of high-performance catalysts.
研究领域:
化学工程
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材料科学
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
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2018
·Vol. 10
·期 24
·5689-5697
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IF 4.674
Wei Hong,Zhi-Qiang Wang,Shihui Zou,Yuheng Zhou,Linfang Lu,Qiuyue Zhou,Xue-Qing Gong,Jie Fan
Graphical Pt does it again ! The morphology of Pt nanoparticles was successfully regulated by calcinating Pt/SiO 2 catalysts in different atmospheres and achieved a 78.1 % cyclohexanone yield at 170 °C in oxidative dehydrogenation of KA-oil. It is industrially attractive to produce cyclohexanone directly from gas-phase oxidative dehydrogenation (ODH) of KA-oil (a mixture of cyclohexanone and cyclohexanol) since extra alcohol-ketone separation process can be potentially omitted. Herein, by simply tuning the calcination atmosphere of Pt/SiO 2 , we successfully regulated the morphology of Pt nanoparticles and optimized their catalytic performance in ODH of KA-oil. Pt/SiO 2 calcined in O 2 atmosphere showed a cube-like morphology and achieved a 78.1 % cyclohexanone yield at 170 °C, which surpassed its counterpart calcined in H 2 and most of the reported catalysts. Further experimental and theoretical calculation results indicated that cubic Pt nanoparticles possessed stronger adsorption ability to cyclohexanol and therefore performed better in ODH of KA-oil.
研究领域:
催化
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
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2015
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IF 3.615
Ze Feng,Yujia Xie,Fang Hao,Pingle Liu,He'an Luo
A series of manganese metalloporphyrins were prepared and tested in cyclohexane oxidation. It has been found that the manganese 5,10,15,20-tetrakis(4-nitrophonyl) porphyrin (Mn-TNPP) presents better catalytic performance. The Mn-TNPP was then immobilized on different supports, and characterized by UV–vis, FT-IR, XRD, TG/DTG and ICP. Among these supported Mn-TNPP catalysts, Mn-TNPP/ZnO exhibits the best selectivity to KA oil and higher turnover number in cyclohexane oxidation. The influence of the reaction conditions and the recycle of the catalysts are discussed. Mn-TNPP/ZnO catalyst presents the average cyclohexane conversion of 7.17%, KA oil selectivity of 91.18%, and the average catalytic turnover number of 6.53 × 10 4 after six times of recycle under 150 °C and 1.0 MPa.
研究领域:
催化化学
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有机合成
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工业化学
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材料化学
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绿色化学
✓ 已验证
DOI
高影响因子
CARBON
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2020
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IF 8.821
Cai Xu,Leilei Jin,Xiaozhong Wang,Yingqi Chen,Liyan Dai
In heterogeneous catalysis , developing robust catalysts and preventing the metal leaching during the reactions still remain challenging. Herein, a porous honeycomb-like nanostructure with bimetallic Ce–Cr oxide supported on N-doped carbon was prepared via a facile in-situ pyrolysis method. The prepared catalyst was highly active, selective, and stable in the transformation of cyclohexane to KA oil with H 2 O 2 as the oxidant. The N-doped carbon served as an excellent support for the metal nanoparticles and greatly promoted their dispersion, and displayed a comparable or superior catalytic activity compared to the other traditional supports. It was found that the pyridinic N and pyrrolic N species of N-doped carbon were the main active sites for the metal immobilization , and the strong electronic interaction between N-doped carbon and Ce–Cr oxide was formed. The results revealed that the increased low-valence metal species might be responsible for the improved catalytic activity, and EPR analysis indicated that the hydroxyl radicals played a crucial role during the oxidation process . Besides, the catalyst can be easily separated and still remained stable after recycling seven times, making it a promising candidate for the catalytic oxidation of cyclohexane to KA oil under mild conditions.
研究领域:
催化化学
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材料科学
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
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2014
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IF 3.679
Yujia Xie,Fengyong Zhang,Pingle Liu,Fang Hao,He’an Luo
Metalloporphyrin-catalysed direct functionalization of saturated C H bonds is one among the topical and challenging areas within the chemical industry. In this work, three types of unsupported and boehmite supported trans-A 2 B 2 -metalloporphyrin chloride complexes (Co-D( p -Cl)PPCl, Fe-D( p -Cl)PPCl, Mn-D( p -Cl)PPCl) were prepared and characterized. It has been found that these trans-A 2 B 2 -metalloporphyrins have high catalytic activity in cyclohexane oxidation under dioxygen. The boehmite supported metalloporphyrins show better catalytic performance and are more stable than unsupported metalloporphyrins. Among these supported metalloporphyrin catalysts, Co-D( p -Cl)PPCl/BM was better than Fe-D( p -Cl)PPCl/BM and Mn-D( p -Cl)PPCl/BM, the cyclohexane conversion and selectivity to KA oil are 6.83% and 83.30%, respectively, and the turnover number is 1.05 × 10 7 . The Co-D( p -Cl)PPCl/BM catalyst can be facilely recovered and was recycled up to six times without significant decrease in catalytic performance.
研究领域:
化学工业
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Junlei Wang,Kuan Wang,Zhen-Hong He,Rong-Rong Zhang,Pengfei Guo,Weitao Wang,Yang Yang,Zhao-Tie Liu
Photocatalytic oxidation of cyclohexane (CHA) with air in solvent-free is an efficient and green approach for the production of cyclohexanol and cyclohexanone (KA oil). In the present work, ultrathin Bi 2 WO 6 /BiOCl heterojunction nanosheets are prepared by varying the amounts of potassium chloride (KCl) via a one-step solvothermal method. The oxygen vacancies (OV) in Bi 2 WO 6 /BiOCl nanosheets can be produced in situ during the photocatalysis. An efficient and selective photo-oxidation of CHA to KA oil with air as an oxidant in solvent-free was achieved over OV-Bi 2 WO 6 /BiOCl catalyst. The composition, structure, morphology, as well as textural, optical, and electrochemical properties of the photocatalysts are systematically analyzed by various characterization techniques. The photocatalytic activity (KA oil, 484.4 μmol) for the titled reaction was significantly improved over OV-Bi 2 WO 6 /BiOCl with 1.8 and 9.8 times compared with that by pure BiOCl and Bi 2 WO 6 catalysts, respectively. Meanwhile, up to 92.5% selectivity of KA oil and 5 cycles without photocatalytic activity loss were achieved. The photogenerated holes (h + ) and ·OH radicals are verified to be predominant reactive species by trapping experiments and electron paramagnetic resonance (EPR) tests. The excellent photocatalytic performance can be attributed to the enhanced photo-absorption, abundant oxygen vacancies, high exposure of active facets, and efficient electron-hole separation. Thereby, the present work offers a prospective strategy for constructing Bi-based photocatalyst with highly efficient and selective photocatalytic oxidation of CHA.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Kuan Wang,Yi Wang,Dan Wang,Yuan-Xiao Du,Xin-Peng Li,Zhen-Hong He,Huan Wang,Weitao Wang,Yang Yang,Zhao-Tie Liu
The exploration of cost-efficient, environmentally friendly, and high-efficacy photocatalysts for the enhanced selective photooxidation of cyclohexane to KA oil (cyclohexanone (CHA-one) and cyclohexanol (CHA-ol)) is a pivotal challenge in the industrial realm. Herein, the present study focuses on the synthesis of needle-like S-scheme heterojunction photocatalysts with oxygen vacancies, which are achieved by the needle growth integration of nano-sized Nb 2 O 5 particles onto the BiOCl nanosheets. Remarkably, the 40 % Nb 2 O 5 /BiOCl composites exhibited superior performance in the solvent-free photooxidation of cyclohexane at room-temperature and under atmospheric pressure. The production yield of KA oil was 180.3 μmol (CHA-one/CHA-ol molar ratio = 3.5), and exceptional selectivity towards KA oil, reaching up to 99.3 %. The enhanced photocatalytic efficiency in cyclohexane oxidation can be attributed to the unique S-scheme heterogeneous interfaces with specific nanoneedle morphology, which result in the enhanced photonic absorption, effective charge carrier separation, a high density of oxygen vacancies, and the exposure of the highly reactive (001) plane of BiOCl. The excellent interfacial charge separation and transfer pathways of S-scheme heterojunction are disclosed by the in-depth EPR analysis and DFT calculations. These insights highlight the significant potential of the needle-like Bi-based S-scheme heterojunction photocatalysts for the efficient photooxidation of saturated alkanes.
研究领域:
材料科学
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催化化学
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环境科学
✓ 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）