Molecular Catalysis
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2024
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IF 3.9
Meng Xu,Xiaoling Liu,Zhuo Xiong,Yue Wu,Zhen Meng,Yu Zhou,Jun Wang
Furfural is an abundant biomass-derived building block that can be converted into furan-based N-containing compounds through direct reductive amination by using dihydrogen (H 2 ). Nonetheless, the synthesis of furan-based tertiary amines is highly limited via this route. Herein, we reported the straightforward synthesis of MFI zeolite encapsulated Pt nanoparticles and finely modulated the surface electronic state by facilely controlling the reduction process. The constructed catalyst Pt@Z5 effectively catalyzed the amination of furfural with diethylamine for the synthesis of N-ethyl-N-(furan-2-ylmethyl)ethanamine, affording the high yield (>95 %), large turnover number (TON) of 2058, turnover frequency (TOF) of 1029 h −1 , and stable recyclability. Systematic investigations comprising in-situ Fourier transform infrared spectroscopy (FTIR) spectra and kinetic isotope effect (KIE) unraveled that the mild reduction condition allowed the catalyst with a superior affinity towards H atom and beneficial furfural adsorption behavior, accelerating the H 2 activation in the rate-determining step for the conversion of furfural into furan-based amine.
研究领域:
催化化学
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生物质转化
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材料科学
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产品关联
DOI
高影响因子
Catalysts
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2019
·Vol. 9
·期 10
·854
·
IF 3.444
Jian Li,Xiangyu Li,Derun Hua,Xinning Lu,Yujue Wang
A series of gallium-containing MFI (Ga-MFI) zeolites with varying Ga2O3/Al2O3ratios were synthesized using hydrothermal synthesis and tested as catalyst in catalytic fast pyrolysis (CFP) of beech wood for aromatic production. The results show that the incorporation of Ga slightly reduced the effective pore size of Ga-MFI zeolites compared to conventional HZSM-5 zeolites. Therefore, the Ga-MFI zeolites increased the aromatic selectivity for smaller aromatics such as benzene, toluene, andp-xylene and decreased the aromatic selectivity for bulkier ones such asm-xylene,o-xylene, and polyaromatics in CFP of beech wood relative to HSZM-5. In particular, the yield and selectivity ofp-xylene, the most desired product from CFP of biomass, increased considerably from 1.64 C% and 33.3% for conventional HZSM-5 to 2.98–3.34 C% and 72.1–79.6% for the synthesized Ga-MFI zeolites. These results suggest that slightly reducing the pore size of MFI zeolite by Ga incorporation has a beneficial effect on optimizing the aromatic selectivity toward more valuable monoaromatic products, especiallyp-xylene, during CFP of biomass.Keywords:aromatics;biomass;MFI zeolites;gallium;catalytic fast pyrolysis
研究领域:
能源化学
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材料科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2022
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IF 10.53
Li Peng,Zhengqi Wu,Boxuan Wang,Hua Liu,Chun Zhang,Xuehong Gu
Pure silica MFI (Si-MFI) zeolite membranes with desirable hydrophobicity have the potential to separate ethanol/water mixture. However, its separation performance would significantly decrease in the long-term operation due to the presence of silanol groups formed in alkaline media. In this work, silanol-free MFI zeolite membranes were prepared by the incorporation of tungsten in MFI framework. The occurrence of silanol group can be prevented by formation of W–O–Si bridges. The synthesis parameters affected the W-MFI zeolite membranes’ microstructure and separation performance. For 5 wt% ethanol solution, the W-MFI zeolite membranes prepared at optimum condition showed stable separation performance of permeation flux as 2.81 kg m −2 h −1 with separation factor as 32 over 80 h at 60 °C. The membrane was characterized by XRD , DR UV–vis, XPS and 29 Si NMR, and the results confirmed the incorporation of W and the absence of silanol groups. This research showed that W-MFI zeolite membranes are promising candidates for ethanol extraction with high stability.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2022
·
IF 8.047
Haoyu Li,Pengfei Wu,Xianquan Li,Jifeng Pang,Shangru Zhai,Tao Zhang,Mingyuan Zheng
High-performance MFI zeolite supported nickel catalysts were prepared by the ammonia evaporation method for maleic anhydride (MA) conversion to γ-butyrolactone (GBL). According to comprehensive characterizations, the Ni catalysts possessed petal-like morphology and hierarchical structures with meso and micro pores. Nickel species were highly dispersed on the silica support and generated abundant Lewis acid sites (LAS), which effectively activated carbonyl groups in the reactant and accounted for the high activity in MA hydrogenation. Zr species hydrothermally introduced into the catalyst increased the number of LAS and decreased the apparent activation energy for the reaction. The highest GBL yield reached 95.6% over 40Ni-2Zr-MFI with the assistance of 3A zeolite to in-situ remove water byproduct. The catalyst showed reasonably good stability in five-cycle operation thanks to the strong interaction between Ni and support. The reaction route for MA hydrogenation was investigated, in which succinic anhydride (SA-A) served as the major reaction intermediate for GBL formation.
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
CHINESE JOURNAL OF CATALYSIS
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2025
·
IF 17.7
Neng Gong,Quanzheng Deng,Yujiao Wang,Zitao Wang,Lu Han,Peng Wu,Shun'ai Che
Designing Fischer-Tropsch synthesis (FTS) catalysts to selectively produce liquid hydrocarbon fuels is a crucial challenge. Herein, we selectively introduced Co nanoparticles (NPs) into the micropores and mesopores of an ordered mesoporous MFI zeolite (OMMZ) through impregnation, which controlled the carbon number distribution in the FTS products by tuning the position of catalytic active sites in differently sized pores. The Co precursors coordinated by acetate with a size of 9.4 × 4.2 × 2.5 Å and by 2,2 ‘ -bipyridine with a size of 9.5 × 8.7 × 7.9 Å, smaller and larger than the micropores ( ca. 5.5 Å) of MFI , made the Co species incorporated in OMMZ's micropores and mesopores, respectively. The carbon number products synthesized with the Co NPs confined in mesopores were larger than that in micropores. The high jet and diesel selectivities of 66.5% and 65.3% were achieved with Co NPs confined in micropores and mesopores of less acidic Na-type OMMZ, respectively. Gasoline and jet selectivities of 76.7% and 70.8% were achieved with Co NPs confined in micropores and mesopores of H-type OMMZ with Brönsted acid sites, respectively. A series of characterizations revealed that the selective production of diesel and jet fuels was due to the C–C cleavage suppressing of heavier hydrocarbons by the Co NPs located in mesopores.
研究领域:
化学工程
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催化材料
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Quanli Ke,Pengyun Pan,Mei Lu,Guonan Fang,Wei Zhang,Ruina Zhang,Guokai Cui,Xiaopo Niu,Feng Xiong,Ying Zhou,Bo Zhao,Hanfeng Lu
Herein, copper and manganese heteroatoms were incorporated into the siliceous MFI frameworks with high dispersity. When employed in the CO 2 /N 2 binary gas separation, a delicate trade-off for the CO 2 adsorption capacity, adsorption heat and moisture resistance could be realized on the heteroatom-incorporated MFI zeolites, especially the Cu-incorporated one. In order to confirm the role that heteroatoms played in CO 2 adsorption, the textural analyses were then conduced, which proved that the enhanced microporosity may be at the heart of the promoted CO 2 capacity. Next to that, the in situ DRIFTs spectra were continuously tracked during the dynamic adsorption process. Compared to the commercial aluminosilicate analogue, the MFI zeolites with Cu/Mn heteroatoms possesses weaker electrostatic field intensity, which in consequence resulted in their stronger moisture resistance, even in presence of humidity up to 90 RH%. As such, a bottom-up adjustment for the adsorption properties of zeolites in practical environment containing competitive moisture impurity was shown.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
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2025
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IF 6.4
Jiayu Yu,Ke Du,Di Pan,He Li,Ling Ding,Wei Chen,Yahong Zhang,Yi Tang
Simplifying complex synthesis systems containing multiple species into ones with a single classical or non-classical growth path is valuable for understanding their respective mechanisms. However, most zeolite growth involves intertwined classical and non-classical mechanisms, making it crucial to distinguish and modulate their contributions in the original synthetic system. In this study, we presented a method to distinguish and directly quantify the contributions of classical and non-classical crystallization pathways in MFI zeolite synthesis, demonstrating that the dominant pathway could be shifted from non-classical to classical by varying the H2O/SiO2 and ethanol/SiO2 ratios. Our findings showed that reducing the H2O/SiO2 ratio favored the non-classical pathway, while increasing the ethanol/SiO2 ratio promoted the classical mechanism. However, these changes had minimal effect on their crystallization sequences: the non-classical pathway predominated initially, but both pathways intertwined as crystallization progressed. Notably, the shift in crystallization pathway did not significantly affect the acidic properties of the zeolites but had a direct impact on their catalytic performance. The catalytic activity of the resulting ZSM-5 zeolites in furfuryl alcohol etherification correlated with the contribution of the classical pathway, with higher contributions leading to enhanced catalytic activity. This study provides new insights into the zeolite crystallization process, offering a valuable approach for optimizing synthesis conditions and improving catalyst performance.
研究领域:
材料科学
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化学工程
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2025
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IF 13.1
Mingrui Xu,Bofeng Zhang,Rongrong Zhang,Liming Xia,Guozhu Liu
Structural transformation under in situ reaction conditions plays a vital role in heterogeneous catalytic performance, especially caused by metal migration. However, the migration of active components often leads to irreversible structural disruption at high temperatures, which could be associated with the deactivation of catalysts. Here, we report a low-melting-point Zn migration-mediated strategy to synthesize ultrastable isolated PtFe3 sites anchored in MFI zeolite for propane direct dehydrogenation. The optimized catalyst exhibited a superior specific activity of 36.5 mol C3H6 molPt–1 s–1 with propylene selectivity above 99% at 550 °C. Moreover, the dehydrogenation activity remained stable after over 400 h on stream with a low deactivation rate constant of 0.001 h–1 under industrial conditions at 580 °C. In situ characterizations demonstrated that Fe3+ species were conducive to the rearrangement in the electronic configuration of the unoccupied 5d states of Pt atoms to form electron-deficient Pt sites. This strategy could afford insights into the dynamic evolution of catalyst preparation in heterogeneous processes.
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
·
2022
·
IF 10.383
Chao Miao,Shumei Chen,Kaixuan Shang,Lixing Liang,Jing Ouyang
The dry reforming of methane (DRM) is a new potential technology that converts two major greenhouse gases into useful chemical feedstocks. The main challenge faced by this process is maintaining the catalyst with high catalytic activity and long-term stability. Here, a simple and effective preparation route for the synthesis of functional nanomolecular sieve catalysts (NiRuxCZZ5) from kaolinite tailings was developed for dry reforming of methane with CO2. The silica monoliths with flower-like spherical and micropore structures (ZSM-5) were prepared by crystal growth method, and the metal components were loaded by ultrasonic-assisted impregnation method. The NiRu0.5CZZ5 catalyst exhibited excellent catalytic performance (maxmium CO2 and CH4 conversions up to 100 and 95.6%, respectively) and very good stability (up to 100h). The interfacial confinement and the strong support interaction are principally responsible for the excellent catalytic activity of the catalyst. The in situ DRIFTS was used to elucidate the possible carbon conversion steps, and stable surface intermediates were also identified.
研究领域:
催化化学
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材料科学
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环境工程
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产品关联
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Kaiwei Wang,Fumin Wang,Yi Zhai,Xubin Zhang,Mingshuai Sun,Jinjin Zhang,Xiaolu Fan,Changhao Bing
The metal species embedded in specific positions within the zeolite framework and their unique microenvironment exhibit fascinating effects on catalytic performance. Herein, we incorporated tetrahedrally coordinated Co 2+ into the framework of hollow silicate-1 zeolite and investigated the influence of halogen anions (Cl - , Br - and F - ) in the synthesized gel on the distribution of cobalt species in the channels. The addition of an appropriate amount of inorganic ammonium salts and seeds was found to be a necessary condition for cobalt incorporated into the framework. Notably, the Cl - anions present in the synthesis gel can induce more cobalt species located at the intersection cavity of silicate-1 (β-type). Comprehensive characterization results indicate that the tetrahedrally coordinated Co 2+ in the intersecting cavities of hollow zeolite appears to exhibit more efficient styrene epoxidation performance. This work presents a simple and cost-effective method to synthesize hollow cobalt-based zeolite with adjustable metal distribution in channels. By regulating the spatial distribution of cobalt species with halogens, the CS-0.1–0.5-Cl catalyst enhanced activity and selectivity in the epoxidation reaction of styrene to styrene oxide. Specifically, at a temperature of 80 °C after a reaction time of 6 h, the catalyst demonstrated a styrene oxide yield of 42.47 % and a excellent styrene oxide selectivity of 82.29 %.
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
·
2024
·
IF 8.3
Jiajie Ye,Xuan Tang,Lu Cheng,Shoujie Zhang,Wangcheng Zhan,Yanglong Guo,Li Wang,Xiao-Ming Cao,Kuan-Wen Wang,Sheng Dai,Yun Guo
Metal/metal oxide clusters possess a higher count of unsaturated coordination sites than nanoparticles, providing multiatomic sites that single atoms do not. Encapsulating metal/metal oxide clusters within zeolites is a promising approach for synthesizing and stabilizing these clusters. The unique feature endows the metal clusters with an exceptional catalytic performance in a broad range of catalytic reactions. However, the encapsulation of stable FeOx clusters in zeolite is still challenging, which limits the application of zeolite-encapsulated FeOx clusters in catalysis. Herein, we design a modified solvent-free method to encapsulate FeOx clusters in pure siliceous MFI zeolites (Fe@MFI). It is revealed that the 0.3–0.4 nm subnanometric FeOx clusters are stably encapsulated in the 5/6-membered rings intersectional voids of the pure siliceous MFI zeolites. The encapsulated Fe@MFI catalyst with a Fe loading of 1.4 wt % demonstrates remarkable catalytic activity and recycle stability in the direct oxidation of methane, while also promoting the direct oxidation of cyclohexane, surpassing the performance of conventional zeolite-supported Fe catalysts.
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
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Yu Gu,Zhiqiang Tao,Shujia Zhang,Xiaohui Wang,Hao Yan,Xinmei Liu,Lei Wang,Jun Xu,Hui Shi
Methane–propane coaromatization (MPCA) upgrades two abundant and inexpensive light alkanes into value-added aromatic products. While Ga-loaded MFI zeolites represent by far the most promising catalysts for MPCA reaction, they often contain a sizable portion of Ga species at the external surface of zeolites, which are remote from the Brønsted acid sites (BAS) within MFI pores and thus inefficient for MPCA. Here, we show that Ga can be introduced into MFI pores at fairly high loadings via a simple cocrystallization approach, yielding catalysts possessing well-dispersed Ga sites predominantly residing inside the pores and framework. Adjacency between Ga and BAS within the constraints of MFI channels makes these (Ga, Al)-H-MFI catalysts more active toward methane and propane activation and more selective toward aromatics compared to the Ga/MFI counterparts prepared by impregnation that inevitably leaves a large fraction of Ga at the external surface (i.e., without confinement and few adjacent BAS). Further, the effects of the Si/Al ratio on MPCA performance have been investigated for (Ga, Al)-H-MFI catalysts. Due to the multifold roles of BAS in the overall reaction sequence, an increased BAS concentration generally results in higher propane conversion and productivity of aromatics together with lower net methane conversion and severer coking.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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