APPLIED CATALYSIS A-GENERAL
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2020
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IF 5.006
Peng Zhang,Ziyan Wang,Yan Zhang,Jian Wang,Wenqing Li,Lina Li,Peiping Zhang,Cundi Wei,Shiding Miao
In this work a Pd/Fe-Co-Ni layered double hydroxide (LDH) composite was prepared and investigated in the semi-hydrogenation of 2-methyl-3-butyn-2-ol (MBY). Hollow nanocages of ternary Fe-Co-Ni LDH were constructed by stacking the LDH nanosheets edge-to-face which inherited the rhombic dodecahedral structure of ZIF-67 templates. Uniform palladium (Pd) nanocrystals with cubic shapes were imbedded in the LDH nanocages via a solvothermal method. The hydroxyl groups on LDH supports were critical to inhibit the association of excess hydrogen atoms on the catalyst, so less MBY molecules were converted to 2-methyl-2-butanol (MBA) during the hydrogenation catalysis. Under optimized reaction conditions the hydrogenation activity of Pd/Fe-Co-Ni LDH was significantly improved, and the conversion of MBY was higher than 99% with selectivity of 2-methyl-3-buten-2-ol (MBE) exceeding 99%. The catalyst was easily recovered and had little reduction in catalytic performance during the cycling reactions.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2019
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IF 7.723
Lei Yang,Shiyi Yu,Chong Peng,Xiangchen Fang,Zhenmin Cheng,Zhiming Zhou
A series of nonprecious monometallic Ni/AlSBA-15 and bimetallic Ni M (M = Zn, Ga, Cu, or Fe)/AlSBA-15 catalysts were prepared using a urea precipitation method and applied to the semihydrogenation of phenylacetylene. The catalysts were characterized by various techniques, showing that the Ni particle size of catalyst can be tuned by adjusting the Al content, and NiZn and NiGa supported catalysts exhibited geometric and electronic effects that originated from the bimetallic alloy. Among all the catalysts studied, NiZn 3 /AlSBA-15, with a turnover frequency of 10.89 s −1 comparable to that of precious Pd-based catalysts, presented the highest selectivity to styrene (90.3%) at nearly 100% conversion of phenylacetylene in semibatch operation. This catalyst was further evaluated in a continuous fixed-bed reactor for semihydrogenation of a model C 8 aromatic fraction of pyrolysis gasoline (a mixture of phenylacetylene, styrene, ethylbenzene and xylene), which aimed at assessing its practical application of recovering styrene from pyrolysis gasoline. The results showed that at complete conversion of phenylacetylene, the styrene concentration in the product was always kept at a stable level and higher than its initial concentration over 100 h of time on stream, demonstrating high selectivity and good stability of NiZn 3 /AlSBA-15. Finally, the application of NiZn 3 /AlSBA-15 was extended to other phenylacetylene derivatives.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Jianguo Liu,Nan Wang,Jianan Liu,Ming Li,Ying Xu,Chenguang Wang,Yanzhi Wang,Haoquan Zheng,Longlong Ma
Highly selective catalytic hydrogenation of alkynes to alkenes is a highly important reaction owing to its industrial and commercial application. Specifically, semihydrogenation of terminal alkynes has been more challenging than internal alkenes even using Lindlar catalysts. Also, the high reduction degree state metal-supported catalysts like Pd0/C, Pt0/C, and Ru0/C have been well-known to be used widely in hydrogenation due to their super activity. However, charcoal can absorb a large amount of water; Pd/C with 50% water is convenient on a large-scale synthesis. Charcoal generally bears oxygen groups on its surface, which are responsible for low selectivity and undesired products. Even typically, only 10–60% of the Pd metal atoms are exposed, they still suffer from poor stability in acids owing to leaching. Herein, we intend to design active and stable metal catalysts with features as the following to avoid leaching: having strong interaction with the support and coordinatively unsaturated metal sites or low valence state metals physically isolated from the acid environment. Herein, a highly efficient semihydrogenation of terminal alkynes to produce alkenes has been realized using a heterogeneous Pd(II)/POP-GIEC catalyst, imine-linked, crystalline, and porous organic polymer supporter modified by coordination of Pd(OAc)2 to its walls under mild conditions. Surprisingly, for the first time, modified POP-supported low reduction degree PdII catalysts were synthesized efficiently, and they were successfully used in semihydrogenation of terminal alkynes. The substrate scope was studied and included both unfunctionalized as well as functionalized substituents on the para, ortho, and meta position of aromatic alkynes. The substrate having a substituent with the functionality of fluoro protected at the meta position was semihydrogenated with a high alkyne conversion of 100% and olefin selectivity (up to 99%).
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
JOURNAL OF CATALYSIS
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2021
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IF 7.92
Jianguo Liu,Shanshan Lin,Jiangming Sun,Longlong Ma
Transition metal-catalyzed semi-hydrogenation of alkynes has become one of the most popular methods for alkene synthesis. Specifically, the noble metal Pd, Rh, and Ru-based heterogeneous catalysts have been widely studied and utilized in both academia and industry. But the supported noble metal catalysts are generally suffering from leaching or aggregation during harsh reaction conditions, which resulting low catalytic reactivity and stability. Herein, we reported the facile synthesis of nitrogen doped graphene encapsulated Pd catalyst and its application in the chemo-selective semi-hydrogenation of alkynes. The graphene layer served as “bulletproof” over the active Pd Nano metal species, which was confirmed by X-ray and TEM analysis, enhanced the catalytic stability during the reaction conditions. The optimized prepared Pd@N/C catalyst showed excellent efficiency in semi-hydrogenation of phenylacetylene and other types of alkynes with un-functionalized or functionalized substituents, including the hydrogenation sensitive functional groups (NO 2 , ester, and halogen).
研究领域:
化学
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材料科学
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催化反应
✓ 已验证
DOI
高影响因子
Nature Communications
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2024
·Vol. 15
·期 1
·1-9
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IF 14.7
Liu Qiaoxi,Xu Wenjie,Huang Hao,Shou Hongwei,Low Jingxiang,Dai Yitao,Gong Wanbing,Li Youyou,Duan Delong,Zhang Wenqing,Jiang Yawen,Zhang Guikai,Cao Dengfeng,Wei Kecheng,Long Ran,Chen Shuangming,Song Li,Xiong Yujie
Hydrogen spillover widely occurs in a variety of hydrogen-involved chemical and physical processes. Recently, metal–organic frameworks have been extensively explored for their integration with noble metals toward various hydrogen-related applications, however, the hydrogen spillover in metal/MOF composite structures remains largely elusive given the challenges of collecting direct evidence due to system complexity. Here we show an elaborate strategy of modular signal amplification to decouple the behavior of hydrogen spillover in each functional regime, enabling spectroscopic visualization for interfacial dynamic processes. Remarkably, we successfully depict a full picture for dynamic replenishment of surface hydrogen atoms under interfacial hydrogen spillover by quick-scanning extended X-ray absorption fine structure, in situ surface-enhanced Raman spectroscopy and ab initio molecular dynamics calculation. With interfacial hydrogen spillover, Pd/ZIF-8 catalyst shows unique alkyne semihydrogenation activity and selectivity for alkynes molecules. The methodology demonstrated in this study also provides a basis for further exploration of interfacial species migration.
研究领域:
催化化学
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材料科学
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表面科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Mingshuai Sun,Fumin Wang,Guojun Lv,Xubin Zhang
S-containing silane coupling agents (SCA) with various structures were chosen as regulators to synthesize PdC nanoparticles in different sizes for semi-hydrogenation of acetylene. Characterization and catalytic performance demonstrate that the catalytic property of PdC is deeply influenced by particle size. PdC particles prepared by employing SCA containing sulfhydryl has a smaller size and narrow diameter distribution. They exhibited better inhibition on ethane formation than those by containing thioether bond. Catalysts with larger PdC particles have lower selectivity to C4 and green oil. Reaction paths on typical (1 1 1) surface of PdC nanoparticles with different dimensions were investigated by DFT calculations. It reveals that within a certain particle size range (∼2.6 nm), surfaces of smaller PdC particles have weaker adsorption strength of ethylene. As particle size exceeds 2.6 nm, the adsorption strength no longer increases. C4 and green oil are more likely to be generated when PdC particles are around 2 nm, and the size smaller or larger than 2 nm will weaken the tendency of C4 and green oil formation.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Yingna Wang,Zilong Liu,Yuanpei Lan,Chaoyi Chen,Wei Zhang
The removal of small amounts of phenylacetylene from styrene is a crucial step in the production of high-quality styrene feedstocks. In the presence of a large amount of styrene and a small amount of phenylacetylene, achieving and maintaining high selectivity of styrene remains a significant challenge. In this work, a catalyst denoted as Pd 1.25 -Fe-N-C/VC was designed and synthesized with remarkably low Pd loading (the actual Pd content was 0.96 wt%). The catalyst exhibited a satisfactory selectivity for styrene (>95 %) and maintained high selectivity levels (>90 %) in the semi-hydrogenation of phenylacetylene even with prolonged reaction time. Pd nanoparticles (NPs) were well distributed and securely anchored onto the Fe-N-C/VC support with a hierarchical mesoporous structure, which obtained from the pyrolysis of a hexagonal star-like Fe-doped zeolitic imidazolate framework with vitamin C surfactant (Fe-doped ZIF/VC). The remarkable catalytic properties may be partly ascribed to the effective synergy effect of the uniformly well-dispersed Fe-N x (x represents the coordination number) with Pd active centers, which could modulate the adsorption kinetics of the reactant alkynes and alkenes and thus enhancing the selectivity towards styrene. Meanwhile, the hierarchical mesoporous structure is beneficial for the mass transfer, which can effectively promote the interactions between the reactants and active centers. Possible mechanism for the selective hydrogenation of phenylacetylene catalyzed by Pd 1.25 -Fe-N-C/VC was also illustrated. Moreover, the Pd 1.25 -Fe-N-C/VC catalyst exhibited sustained catalytic activity and selectivity even after four continuous cycle tests, showing notable reusability and stability. This work may offer a promising approach for creating highly efficient Pd-based catalysts with remarkably low Pd loading for phenylacetylene semi-hydrogenation.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
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2024
·
IF 3.9
Zuwei Luo,Yun Shen,Di Fang,Chuanchao He,Yueqiang Cao,Wei Li,Yi-An Zhu,Jinghong Zhou,Xinggui Zhou
Support materials play vital roles in heterogenous catalysis via the so-called support effects, and understanding on the support effects is beneficial for the design of high-performance catalysts. Herein, we represent detailed investigations on the support effects of Ag catalysts for dimethyl glycolate (DMO) semi-hydrogenation to methyl glycolate (MG), where G6 silica with amorphous mesopores, SBA-15 with parallel mesopores and silica nanospheres (MSNS) with center-radial ones were employed as the supports. The hydrogenation activity decreases in the order of Ag/MSNS > Ag/SBA-15 > Ag/G6 while the MG selectivity in the order of Ag/G6 > Ag/MSNS > Ag/SBA-15 at the same reaction conditions, indicating remarkable support effects on both activity and selectivity. Structural characterizations, temperature programmed experiments and in-situ FTIR of DMO adsorption experiments demonstrate that the weak confinement effect of G6 leads to the larger sized Ag nanoparticles and weakened activation of DMO and H 2 , which contributes to low hydrogenation activity. In contrast, the ordered mesoporous SBA-15 and MSNS deliver well confinement effects for Ag nanoparticles and the activation of DMO and H 2 , but the distinct pore structures result in different activation and diffusion behaviors. Finally, DMO conversion and MG yield are well correlated with the competitive adsorption of H 2 versus DMO on Ag catalysts, indicating such competitivity as a descriptor for DMO semi-hydrogenation over Ag catalysts.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Junjie Tang,Peiwen Liu,Xiaoling Liu,Lei Chen,Haimeng Wen,Yu Zhou,Jun Wang
Straightforward encapsulation of Pt clusters (∼2 nm) into the pure silica TON-type zeolite (ZSM-22) was reached in a dry gel conversion route, where the ionic liquid template was removed via the hydrocracking-calcination-reduction approach. The obtained Pt@ZSM-22 series possessed high crystallinity, large surface area, and ultrafine Pt clusters inside the zeolite crystals. They exhibited remarkable activity in the semi-hydrogenation of phenylacetylene into styrene; the lead sample with 0.2 wt % Pt loading afforded a large turnover number up to 117,787. The preferential high affinity of the pure silica ZSM-22-encapsulated Pt clusters toward the substrate phenylacetylene rather than the hydrogenated product was derived from the unique space-confinement effect of zeolite microchannels, which is responsible for such excellent performance.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Chemistry
·
2021
·
IF 8.301
Z. Tian,C. Dong,D. Li,G.-H. Wang
Semihydrogenation of alkynes to alkenes is an important and fundamental reaction in many industrial and synthetic applications and often suffers low selectivity because of the overhydrogenation. Here, highly selective semihydrogenation of alkynes is achieved by using H 2 ex situ generated from formic acid dehydrogenation with palladium (Pd)-based bimetallic catalysts through a two-chamber reactor in this work, realizing efficient utilization of H 2 and selective production of alkenes under mild reaction conditions. The Pd-based bimetallic catalysts show excellent catalytic performances for semihydrogenation of alkynes (PdZn bimetallic catalyst) and dehydrogenation of formic acid (PdAg bimetallic catalyst) in the two-chamber reactor.
研究领域:
催化化学
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材料科学
·
有机合成
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yaxin Xing,Yatao Su,Luyao Li,Zengli Jia,Gang Feng,Hongchao Wang,Yuangong Zhang,Xin Wen
The practical application of non-noble metal-based hydrogenation catalysts is limited because of their low activity and easy oxidation in air. Here, porous silica-supported ultrafine nickel oxide (NiO) was prepared by calcining an organic–inorganic hybrid 3D nanomaterial that was formed via the Michael addition/Schiff’s base reaction, and hydrolyzation of triethoxysilane. NiO nanoparticles with ca. 2.6 nm diameter was uniformly dispersed and confined in the cogenerated mesoporous SiO 2 skeleton, thanks to the coordination between pyrogallol/amino units and Ni 2+ ions, and the isolation effect of Si-O-Si network. The as-prepared catalyst featured mesoporous structure and high specific surface area (715 m 2 /g), and exhibited excellent activity, selectivity and reusability in the semi-hydrogenation of alkynes. Small amount of metallic nickel (Ni x -NiO) that formed on the surface of NiO nanoparticles during the semi-hydrogenation acted as the active species, and the moderate adsorption/desorption energies on Ni x -NiO facilitated the activity enhancement. Most importantly, it showed constant catalytic activity and selectivity after a long-term storage in air. This work provides a green and feasible strategy, as an alternative to the traditional impregnation method, for the preparation of ultrafine metal-supported catalysts with air-stability and reusability.
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
危险品化学品经营许可证（带存储）