APPLIED CATALYSIS A-GENERAL
·
2009
·Vol. 358
·期 2
·173-179
·
IF 3.19
Guan Huang,Shang-Yue Liu,Yong-An Guo,Ai-Ping Wang,Jin Luo,Chun-Cai Cai
The search for a reusable material as an efficient and economic catalyst for hydrocarbon oxidation is an important field of research. In this study, we investigated the highly effective combination of support and metalloporphyrin provided by manganese tetraphenylporphyrin adsorbed onto a precursor of freshly precipitated aluminium hydroxide, followed by conversion to a manganese porphyrin/boehmite compound. This was characterized using FT-IR, UV–vis spectroscopic techniques, N 2 BET analysis, X-ray powder diffraction, transmission electron micrograph technique and thermal analysis. Aerobic oxidation of cyclohexane has been investigated using the compound as a catalyst under mild conditions and in the absence of any solvent and reductant. The results indicate that it has higher catalytic activity than manganese tetraphenylporphyrin and the corresponding chitosan-supported catalyst. In particular, the catalyst exhibits good atom economy for cyclohexane oxidation, high catalyst turnover number, and good ketone and alcohol selectivity. In particular, it has excellent reusability, with no change in original catalytic activity; a quantity of catalyst containing only 1 mg of Mn TPP can be reused 8 times under the promotion of beomite (BM). In addition, we examined the reaction conditions for the use of such nanoparticle-supported manganese tetraphenylporphyrin as a mild and environmental friendly oxidation catalyst.
研究领域:
催化化学
·
纳米材料
·
绿色化学
·
有机氧化反应
·
多相催化
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2015
·
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
·
有机合成
·
工业化学
·
材料化学
·
绿色化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2019
·
IF 7.723
Yuanyuan Ma,Zhongling Lang,Jing Du,Likai Yan,Yonghui Wang,Huaqiao Tan,Shifa Ullah Khan,Yang Liu,Zhenhui Kang,Yangguang Li
Selective reduction of nitroarenes is extremely valuable in industrial chemical production. The main reduced products are usually aniline derivatives obtained using single-component noble- or transition-metal catalysts; however, other important products such as hydrazobenzene derivatives always involve in harsh conditions and multiple reaction steps. Here, we realize an unexpected switchable reduction of nitroarenes into aniline or hydrazobenzene derivatives with high yield and selectivity just by controlling the molar ratio of nitroarenes to N 2 H 4 ·H 2 O with a nickel–tungsten carbide composite nanocatalyst loaded on carbon (Ni-WC/C). A series of control experiments and density functional theory (DFT) calculations indicate that the multiple interfaces between Ni and WC can induce a synergistic effect, significantly modulating the electronic structure of the Ni-WC/C catalyst, and endowing the catalyst with switchable selectivity and high activity for the reduction of nitroarenes by hydrogenation. This synergistic multi-interfacial catalyst may offer a new way to design and explore highly efficient and selective catalysts for the controllable reduction of nitroarenes and similar hydrogenation reactions.
研究领域:
催化化学
·
有机合成
·
纳米材料
·
表面科学
·
工业化学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
IF 4.8
Guojun Lv,Xuyang Zou,Yan Chen,Qing Zhang,Xubin Zhang,Fumin Wang
The successful one-pot synthesis of MCM-41/MFI composite is mainly concentrated on the trivalent heteroatom of Al 3+ and Fe 3+ , however there are almost no reports about the one-pot synthesis of Ti-MCM-41/MFI composite. In this work, we reported the one-pot synthesis of Ti-MCM-41/MFI composite with a temperature-gradient hydrothermal strategy using hexadecyl trimethylammonium bromide CTAB and silicalite-1 seed as structure directing agents as well as ammonia solution as alkali source, and its application as heterogeneous catalyst in the cyclohexene epoxidation reactions. The impact of Si/Ti molar ratio and ammonia dosage as well as CTAB amount on the formation and property of Ti-MCM-41/MFI composite were systematically investigated. In addition, a possible partial transformation mechanism of Ti-MCM-41/MFI composite sample was proposed. The synthesized Ti-HMZ-50-N3.77-Se0.05 sample with ordered mesoporous structure and high content of framework titanium active centers revealed the eminent cyclohexene epoxidation performance, achieving a 32.51 % of cyclohexene conversion and a 61.27 % selectivity of cyclohexene oxide within 5 h of reaction.
研究领域:
催化化学
·
材料化学
·
纳米材料
·
多相催化
·
绿色化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 128
·105747-105752
·
IF 3.84
Yuanyuan Zheng,Xiaoming Zhang,Yi Yao,Xiaohong Chen,Qihua Yang
Ultra-small Au nanoparticles (<2 nm) supported on hollow silica nanospheres were successfully fabricated with the aid of chemical modification (–SH groups) or through simple immersion method, leading to supported catalysts Au/SH-HNS and Au/HNS. The resulting solid catalysts showed good thermal stability and the small particle sizes could be remained even at high temperature of 350 °C. Such catalysts were catalytically active in the oxidation of styrene using O2 as oxidant under 1 atm pressure. The catalytic results showed that the activity strongly depends on the Au loading amount, and the loading of 4–5 wt% led to the highest activity. Significant rate enhancement was observed with gold nanoparticles supported on pure silica in comparison with thiol modified silica nanospheres, suggesting the negative effects of thiol groups. The solid catalyst could be reused at least 8 reaction cycles without significant decrease in activity and selectivity. This study not only supplies an active, recoverable catalyst for the green transformation of styrene, but also demonstrates that the hollow silica nanosphere material has a superior ability in stabilizing metal nanoparticles against growth.
研究领域:
纳米催化
·
材料化学
·
绿色化学
·
有机氧化反应
·
多相催化
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Jing Guo,Shanhui Zhu,Youliang Cen,Zhangfeng Qin,Jianguo Wang,Weibin Fan
A series of ordered mesoporous Nb x W (8 − x) oxides with tunable Nb/W ratio were successfully synthesized by evaporation-induced self-assembly method. The mesoporous structure, morphologies, surface chemical state, and acidic properties of these catalysts were fully characterized by low-temperature sorption of N 2 , small-angle and wide-angle XRD, TEM, Raman, XPS, and Py-IR. It was shown that the Nb x W (8 − x) oxides created large amounts of Lewis as well as Brønsted acid sites, which promoted the isomerization of glucose to fructose followed its dehydration to 5-hydroxymethylfurfural (HMF). Mannose was also formed via the epimerization of glucose. Of them, the mesoporous Nb 4 W 4 exhibited the best catalytic activity with a comparatively low E a about 90.2 kJ/mol and good stability in aqueous medium. The kinetic behavior revealed that Lewis acid sites facilitated to glucose-to-fructose isomerization while Brønsted acid sites promoted the dehydration of fructose to form HMF.
研究领域:
催化化学
·
生物质转化
·
绿色化学
·
多相催化
·
材料化学
·
碳水化合物化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Dewang Zeng,Yu Qiu,Min Li,Li Ma,Dongxu Cui,Shuai Zhang,Rui Xiao
Chemical looping redox cycle of oxygen storage materials offers a versatile platform to convert methane to value-added products in a clean and efficient manner. However, the highly dynamic nature of the oxygen diffusion process restrains the selective formation of the target products over a long reaction period. In this work, we show the oxygen storage materials-comprising of iron oxides and zirconium oxide support, with the nickel catalyst controllably deposited—that significantly enhanced the syngas selectivity. Mechanistic study indicated the oxygen releasing rate can be well controlled within a long reaction period by the specific spatial structure, demonstrating a new strategy to tune the oxygen diffusion in chemical looping process. Through the observed spatial effects, this work can be also extended to develop more oxygen storage materials for the other chemical looping applications, e.g. methane reforming, methane oxidative coupling, ethane oxidative dehydrogenation, etc .
研究领域:
催化化学
·
能源化学
·
材料化学
·
化学工程
·
多相催化
✓ 已验证
DOI
高影响因子
SURFACE SCIENCE
·
2019
·
IF 1.849
Ting Luo,Ruidan Zhang,Xingxing Peng,Xinting Liu,Chuanyao Zhou,Xueming Yang,Zefeng Ren
Characterizing high-surface-area powders under near-ambient and high-pressure environments has obtained more and more attraction in the field of heterogeneous catalysis in the last decades. Here, we present an easy-operated internal heterodyne phase-resolved sum-frequency generation vibrational spectroscopy (SFG-VS) setup with the z-cut α-quartz as the internal phase reference. It is equipped with CO 2 laser to heat the substrate of α-quartz in a non-contacted way, which enables us to realize high sensitive SFG vibrational spectral measurements under high pressure and high temperature conditions. It has been demonstrated with CO adsorbed on platinum nanoparticles under the high CO pressure and the high temperature environment and sodium dodecyl sulfate film on α-quartz.
研究领域:
物理化学
·
表面科学
·
纳米材料
·
多相催化
·
激光光谱学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2010
·
IF 3.135
Xin Huang,Li Li,Xuepin Liao,Bi Shi
Bayberry tannin (BT), a natural plant polyphenol, was used as a stabilizer to prepare supported platinum catalysts. Bayberry tannin was first grafted onto aminated SiO 2 beads and subsequently coordinate with Pt(IV) species. Then a series of heterogeneous Pt–bayberry tannin–SiO 2 (Pt–BT–SiO 2 ) catalysts was obtained after reduction with NaBH 4 . The catalysts were characterized by UV–DR, XRD and TEM, and the coordination state of Pt(IV) with BT grafted on SiO 2 beads was investigated by XPS. It was found that the Pt–BT–SiO 2 catalysts were highly active and stable in aqueous hydrogenation of acrylic acid, α-methacrylic acid, allyl alcohol and 2-methyl-3-buten-2-ol. Moreover, the Pt–BT–SiO 2 catalysts could be conveniently recovered from the reaction systems simply by filtration, and be reused at least five times without loss of activity.
研究领域:
纳米催化
·
绿色化学
·
材料科学
·
多相催化
·
可持续化学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2019
·
IF 12.221
Wenhui Li,Guanghui Zhang,Xiao Jiang,Yi Liu,Jie Zhu,Fanshu Ding,Zhongmin Liu,Xinwen Guo,Chunshan Song
Cobalt catalysts supported on TiO2 with different crystal forms (anatase and rutile) differ sharply in CO2 conversion and product selectivity for CO2 hydrogenation. The Co/rutile-TiO2 catalyst selectively catalyzed CO2 hydrogenation to CH4, while CO is the main product on the Co/anatase-TiO2 catalyst. In situ DRIFT (diffuse reflectance infrared Fourier transform) results have partially revealed the reaction pathway of CO2 hydrogenation on these two catalysts. On Co/rutile-TiO2, the reaction proceeds through the key intermediate formate species, which is further converted to CH4. Differently, the reaction on Co/anatase-TiO2 undergoes CO2 → *CO, which desorbs to form gas-phase CO instead of subsequent hydrogenation. The strongly bonded *CO is required to enhance the subsequent hydrogenation. By simply changing the calcination temperature of anatase TiO2, the product selectivity can be tuned from CO to CH4 with a significant increase in CO2 conversion due to the surface phase transition of the anatase to the rutile phase. The addition of Zr, K, and Cs further improves the CO, CO2, and H2 adsorption in both the capacity and strength over anatase- and rutile-supported catalysts. The Zr modification makes the reaction pathway over anatase-supported catalyst proceed via the intermediate formate species and enables the subsequent hydrogenation to CH4. In addition, the surface C/H ratio increases significantly in the presence of promoters (unpromoted < Zr-promoted < K-Zr-promoted ∼ Cs-Zr-promoted), which leads to the highest C2+ selectivity of 17% with 70% CO2 conversion over K-Zr-Co/anatase-TiO2 catalyst. These results reveal mechanistic insights into how the product distribution of Co/TiO2 catalysts can be manipulated through adjusting the adsorption performance and surface C/H ratio.
研究领域:
催化化学
·
材料化学
·
多相催化
·
CO2利用
·
表面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2021
·
IF 7.92
Wei She,Jing Wang,Xuewei Li,Jingfang Li,Guijie Mao,Weizuo Li,Guangming Li
One-pot direct synthesis of imines via reductive amination of nitroarenes with aromatic aldehydes remains a great challenge due in part to its over-hydrogenation of imines to secondary amines. Herein, a novel Co 3 ZnC and ZnO supported on N-doped carbon nanosheet catalyst with the thickness of ca. 5.0 nm was fabricated through the direct pyrolysis of a Co/Zn bimetallic MOFs at 500 °C (named as Co 3 ZnC-ZnO/NC-500). Surprisingly, the developed Co 3 ZnC-ZnO/NC-500 catalyst delivers 99.9 % conversion of nitrobenzene and 98.5 % selectivity to N -benzylideneaniline in one-pot reductive amination of nitrobenzene with benzaldehyde. Various characterizations (including as SEM, XRD, TEM, AFM, XPS, Raman and N 2 adsorption–desorption) have revealed that the generated small size of Co 3 ZnC alloy, abundant structural defects, larger specific surface area (105.5 m 2 ·g −1 ) as well as more basic sites are responsible for the outstanding catalytic activity of Co 3 ZnC-ZnO/NC-500 catalyst for tandem reaction. Moreover, the Co 3 ZnC-ZnO/NC-500 catalyst exhibits high stability during the recycling experiments without the loss of its catalytic activity. Notably, the results of contrast experiments have demonstrated that the intentional introduction of ZnO in Co 3 ZnC-ZnO/NC-500 catalyst plays a key role in the selectivity to N -benzylideneaniline in the tandem reaction. This study provides a new guideline for designing tandem catalysts with high selectivity.
研究领域:
材料化学
·
多相催化
·
有机合成
·
纳米材料
·
金属有机框架（MOFs）
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Enhui Wu,Xiaoshan Feng,Yingbin Zheng,Daifeng Lin,Yongjin Luo,Yufeng You,Baoquan Huang,Qingrong Qian,Qinghua Chen
Mn–Co–O catalysts with different Mn/Co molar ratios were synthesized by means of a facile inverse coprecipitation strategy and applied for the oxidation of propane (C3H8). The XRD pattern of Co2Mn1Oδ (molar ratio of Mn:Co = 1:2) indicates a Co3O4 phase, and most Mn incorporates into Co3O4 lattice to form a solid solution. Minor distributed Mn species occur structure reforming, totally converting to a stable Co–Mn solid solution during oxidation process. Meanwhile, Co2Mn1Oδ features a porous core–shell morphology, the core and shell of which are made up of Co–Mn solid solution, giving rise to a high surface area. The optimized synergistic effect of manganese and cobalt improves low temperature reducibility and produces rich surface active Co3+ species and surface-absorbed oxygen over Co2Mn1Oδ. As a result, it exhibits a prominent excellent catalytic activity, and delivers good thermal stability in the presence of 5 vol % H2O and 5 vol % CO2. In situ DRIFTs analysis displays the reaction path of C3H8 over Co2Mn1Oδ, where dominate intermediate species formate are easily decomposed into CO2. The synthesized porous core–shell Mn–Co–O can be a promising candidate replacing non-noble catalysts toward C3H8 oxidation at low temperature.
研究领域:
催化化学
·
环境化学
·
材料科学
·
多相催化
·
能源与环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）