CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2021
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IF 3.171
Chunhua Zhang,Zhengyan Qu,Hong Jiang,Rizhi Chen,Weihong Xing
Phenol hydrogenation is a green route to prepare cyclohexanone, an intermediate for the production of nylon 66 and nylon 6. The development of high-performance catalysts still keeps a great challenge. Herein, the activated carbon (AC) was modified with an acidic material Nb 2 O 5 to adjust the microstructure and surface properties of AC, and the influences of the calcination temperature and Nb 2 O 5 content on the catalytic performance of the Pd/AC-Nb 2 O 5 catalysts for the phenol hydrogenation to cyclohexanone were investigated. The Nb 2 O 5 with proper content can be highly uniformly distributed on the AC surface, enhancing the acidity of the Pd/AC-Nb 2 O 5 catalysts with comparable specific surface area and Pd dispersion, thereby improving the catalytic activity. The hybrid Pd/AC-10Nb 2 O 5 -500 catalyst exhibits the synergistic effect between the Pd nanoparticles and AC-10Nb 2 O 5 , which enhances the catalytic activity for the hydrogenation of phenol. Furthermore, the as-prepared Pd/AC-10Nb 2 O 5 -500 catalyst shows good reusability during 7 reaction cycles.
研究领域:
化学工程
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催化材料
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DOI
高影响因子
Catalysts
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2020
·Vol. 10
·期 3
·302
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IF 3.52
Meng Guo,Zhen Wei,Jianming Yang,Zunyuan Xie,Weiqiang Zhang
In the palladium-catalyzed C−C coupling reaction, electron-rich phosphine ligands and a catalytic amount of catalyst loading are required in most cases. Herein, a bench-stable, easily modified and less toxic alkynone was utilized in palladium-catalyzed Sonogashira coupling to replace conventional phosphine ligands. With 1-(4-methoxyphenyl)-3-phenyl-2-yn-1-one (L2) as the ligand, catalyst loading was reduced to 5-10 ppm. In this newly developed catalytic system, a variety of (hetero)arene iodines and alkynes could be tolerated, resulting in good yields of the corresponding cross-coupling products.Keywords:α;β-alkynone;Pd-catalyzed C−C coupling;π-acidicity
研究领域:
有机化学
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催化化学
✓ 已验证
DOI
高影响因子
Applied Sciences-Basel
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2019
·Vol. 9
·期 9
·1792
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IF 2.217
Anqiu Liu,Xiaochen Wang,Daming Gao,Le Wang,Junjie Cheng,An Wang,Zehui Zhang
Chemoselective hydrogenation of aldehydes with heterogeneous catalysts under mild conditions is of great importance but remains a major challenge. Herein, an efficient strategy was developed for low temperature chemoselective hydrogenation of aldehydes with broad substrate scope over a magnetic material supported palladium catalyst (γ-Fe2O3@HAP-Pd). Aldehydes bearing various reducible functional groups readily underwent hydrogenation to give the corresponding primary alcohols with moderate to excellent yield at room temperature in aqueous solutions. The Hammett equation revealed that the hydrogenation of aromatic aldehydes proceeded via an anionic intermediate. Additionally, when the temperature increased to 70 °C, toluene was obtained by the deoxygenation of benzaldehyde in excellent yield. Furthermore, the γ-Fe2O3@HAP-Pd could be recycled up to six times without loss of activity and metal leaching.Keywords:selective hydrogenation;aldehydes;Pd catalysts;mild conditions
研究领域:
催化化学
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材料科学
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DOI
高影响因子
RSC Advances
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2020
·Vol. 11
·期 1
·48-56
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IF 3.119
Yingjie Hu,Yuxin Mei,Baining Lin,Xuhong Du,Fan Xu,Huasheng Xie,Kang Wang,Yonghua Zhou
The one-pot synthesis of methyl isobutyl ketone (MIBK) and methyl isobutyl methanol (MIBC) from acetone and hydrogen is a typical cascade reaction comprised of aldol condensation-dehydration-hydrogenation. Pd loss and aggregation during long term operation are typical problems in industrial application. In this paper, an active and stable catalyst was achieved with defective UiO-66 as a support for Pd, which was synthesized with the ratio 15 : 1 of ZrOCl2·8H2O to ZrCl4 as Zr-precursors. The resultant Pd catalyst remained active for at least 1000 h with a MIBK + MIBC selectivity of 84.87–93.09% and acetone conversion of 45.26–53.22% in a continuous trickle-bed reactor. Besides the increased Brønsted acid amount generated by the defect sites was favorable for the activity, the cavity confinement in the UiO-66 (R = 15 : 1) structure also efficiently prevented Pd loss and aggregation during the long term run. The contrast of the characterization of the fresh and used Pd/UiO-66 (R = 15 : 1) indicated that the deactivation of the catalyst was attributed to carbonaceous accumulation on the catalyst surface, which could be easily regenerated by calcination. This work supplied a new alternative for the design and utilization of industrial catalysts for MIBK and MIBC synthesis.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Jirui Yang,Xinhua Qi,Feng Shen,Mo Qiu,Richard Lee Smith
Transfer hydrogenation is highly effective for dechlorinating priority organic pollutants in wastewater. Lindane could be completely dechlorinated at room temperature and atmospheric pressure via transfer hydrogenation, in which Pd (3.1 wt%) supported on chitosan-derived porous carbon (3.1Pd@A600) and formic acid (FA) were used as catalyst and hydrogen source, respectively. Favorable catalytic activity of 3.1Pd@A600 is attributed to pyridinic N of the support that allowed Pd nanoparticles to be well-dispersed in the solid and to pyridinic N-Pd interactions that enhanced FA decomposition over that observed for commercial carbon supported Pd catalyst (5Pd@AC). In the reaction system containing 3.1Pd@A600 and FA, 99.7% lindane conversion and 100% dechlorination efficiency could be achieved at 25 °C and atmospheric pressure within 60 min. Benzene and cyclohexane were identified as end-products of lindane dechlorination . The transfer hydrogenation strategy developed in this study has wide application to chlorinated organic pollutants contained in actual waste streams.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELLULOSE
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2017
·Vol. 24
·期 6
·2403-2413
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IF 3.417
Xu Siquan,Yan Xiaopei,Bu Quan,Xia Haian
A series of carbon nanotube (CNT)-supported monometallic Pd and bimetallic Pd–Fe catalysts were synthesized and employed for catalytic hydrogenolysis of cellulose into polyols, including hexitol, ethylene glycol (EG), 1,2-propanediol (1,2-PG), and glycerol (Gly). The physicochemical properties of the catalysts were characterized by nitrogen physical adsorption measurements, X-ray diffraction analysis, transmission electron microscopy, and X-ray photoelectron spectroscopy. The total yield of hexitol, EG, 1,2-PG, and Gly in hydrolytic hydrogenation of cellulose was 37, 55, and 53% for Pd/CNTs, Pd–Fe/CNTs (Pd:Fe = 1:1), and Pd–Fe/CNTs (Pd:Fe = 1:2), respectively. Addition of Fe to Pd significantly modified the physicochemical properties of the nanoparticles and their catalytic performance, especially regarding hexitol selectivity. The promoting effect of Fe, especially for hexitol selectivity, compared with the monometallic catalyst is due to the fact that incorporation of Fe may stabilize Pd 0 nanoparticles and lead to downshift of the d -band center of Pd metal nanoparticles by charge transfer from Fe to Pd. Recycling experimental results showed that leaching of Fe resulted in a significant decrease in the hexitol yield obtained using the Pd–Fe/CNTs after the first recycle, further demonstrating that Fe element plays a promoting role for hexitol formation.
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
JOURNAL OF ORGANIC CHEMISTRY
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2023
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IF 3.6
Chenxu Zheng,Zhi-Jiang Jiang,Ke Jin,Qian Wang,Jian-Fei Bai,Gang Xu,Zhanghua Gao
As a representative scaffold of alkaloids, indoles have been extensively subjected to deuteration, but the regioselective C4 labeling has not been achieved due to its low reactivity. In this work, a Pd-catalyzed deuterium labeling at the indole’s C4 position has been developed under the strategy of transient directing, using D2O as a deuterium source. The substituent effect is found to be crucial in facilitating this H/D exchange process, where the reversing C–D bond formation favors an electron-enriched ligation contrary to its C–H halogenation counterpart.
研究领域:
有机化学
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药物化学
✓ 已验证
DOI
PubMed
高影响因子
SYNTHETIC COMMUNICATIONS
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2018
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IF 1.377
Xinyuan Ma,Qiong Mo,Jie Chang,Kai Xie
This paper mainly studied Pd-catalyzed regioselective chlorination of disubstituted 1,2,3-triazoles directed by the 1,2,3-triazole ring. A series of regioselective chlorinated products were synthesized in 47–86% yields using Pd(OAc)2 as a catalyst and CuCl2 as a chlorinated reagent. This method provides a new mean for the synthesis of 1,2,3-triazole halides which combines the formation of C-X bond with C-H activation.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
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2017
·Vol. 31
·期 12
·e3854
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IF 2.319
Xiaojun Ma,Guanghui Lv,Xu Cheng,Weijian Li,Rui Sang,Yong Zhang,Qiantao Wang,Li Hai,Yong Wu
An environmentally friendly palladium(II) catalyst supported on cyclodextrin-modified h-BN was successfully prepared. The catalyst was characterized by FT-IR, SEM, TG, XRD and XPS, and the loading level of Pd in h-BN@β-CD@Pd(II) was measured to be 0.088 mmol g −1 by ICP. It exhibits excellent catalytic activity for the Suzuki and Heck reactions in water, and can be easily separated and consecutively reused for at least nine times. In addition, a series of pharmacologically interesting products were successfully synthesized using this catalyst to demonstrate its potential applications in pharmaceutical industries. Above all, this work opens up an interesting and attractive avenue for the use of cyclodextrin-functionalized h-BN as an efficient support for hydrophilic heterogeneous catalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
Green Chemical Engineering
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2025
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IF 7.6
Ruan Tao,Zhao Lisha,Ouyang Xinping,Li Lifeng,Zhang Wenwei,Qiu Xueqing
The depolymerization of lignin into aromatic monomers with high yield is the bottleneck of high valued utilization of lignin. In this work, a highly dispersed Pd supported on WO 2.72 (Pd/WO 2.72 ) catalyst was prepared for efficient hydrogenolysis lignin. The highly dispersed Pd, high specific surface area, high content of acidic sites, and hydrogen spillover of Pd/WO 2.72 improved the depolymerization efficiency of lignin. In addition, the depolymerized products were alkylated with the reaction solvent to prevent monomers from re-polymerizing, thus further enhancing aromatic monomers yield. Under 320 º C, 6 h, Bio-oil and aromatic monomers yield reached 77.67% and 28.80%, respectively. Among the aromatic monomers, the tert -butyl group substituted products accounted for 65.71%, of which 77.1% were methoxy-free phenols. It was found that the bio-oil had a calorific value of 38.13 MJ/kg and an IC 50 value of 43 mg/L, showing their potential applications as fuels or antioxidant additives.
研究领域:
化学工程
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可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2018
·
IF 6.759
Yujie Song,Hao Wang,Shijing Liang,Yan Yu,Liuyi Li,Ling Wu
The photoalkylation of nitroarenes with benzyl alcohols in one pot at room temperature and 1 atm N 2 was achieved over the Pd/H 1.07 Ti 1.73 O 4 ·H 2 O nanosheets. The sample shows efficient photocatalytic activity with high conversion of nitrobenzene (99%) and selectivity of secondary amine (85%). This flexible photocatalytic system is also applicable to other nitroarenes with high efficiency. Results of in situ FTIR, DRS, and in situ ESR revealed that the benzyl alcohol and nitrobenzene molecules can bind with the surface Lewis and Brønsted acid sites in the catalyst via the H O⋯Ti and NO 2 ⋯H O Ti species. The formation of surface coordination species results in not only the activation of reactant molecules via surface electron transfer, but also the expanded visible light absorption of the catalyst. Moreover, in situ ESR suggested that the surface coordination can also facilitate the formation of oxygen vacancies in catalysts, which can greatly promote the exposure of Lewis sites and enhance the activation of reactant molecules. Finally, a possible hydrogen transfer strategy over the sample is proposed on a molecular level.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
·
IF 22.1
Nanxing Gao,Dongchen Han,Tongtong Yang,Qinglei Meng,Xian Wang,Changpeng Liu,Junjie Ge,Wei Xing
The importance of the dynamic structural evolution of water in the solid–liquid interface cannot be overstated. However, the ubiquitous hydrogen-bonded network is notoriously difficult to probe owing to complex interfacial environment. Formic acid , a fair hydrogen-bond donor and acceptor, is a promising reversible hydrogen storage/release material. Herein, isotope-labeled in-situ mass spectrometry (MS) and operando surface-enhanced Fourier transform infrared measurements ( operando FT-IR) reveal the central role of water during formic acid dehydrogenation . The water-promoted restructured HCOONa-Pd@ANI/C catalyst exhibits 100% selectivity, 100% conversion yield with high stability (even after 112 days) under ambient conditions. Coupled to a proton exchange membrane fuel cell, this integrated system reaches a high power density at 29.81 W⋅g Pd −1 . Our study demonstrates a new pathway involving water, the indispensable proton transfer and exchange through efficiently hydrogen-bonded network in light of operando experimental evidence.
研究领域:
催化化学
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材料科学
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表面化学
✓ 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）