INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Xiaopo Niu,Xiaoxue Li,Gang Yuan,Fuxiang Feng,Miao Wang,Xiangwen Zhang,Qingfa Wang
Hollow hierarchical silicalite-1 zeolite encapsulated Pt and PtNi bimetals (Pt@HS-1 and PtNi@HS-1) were successfully synthesized via a ship-in-bottle strategy and employed for hydroconversion of methyl stearate into aviation fuel range alkanes in a fixed-bed reactor. Their morphologies, texture, and acidity were characterized by field-emission scanning electron microscopy, field-emission transmission electron microscopy, X-ray diffraction, nitrogen adsorption and desorption, hydrogen temperature-programmed reduction, X-ray photoelectron spectroscopy, inductively coupled plasma optical emission spectrometry, ammonia temperature-programmed desorption, and CO pulse chemisorption. The bimetallic catalysts (PtNi/S-1 and PtNi@HS-1) showed higher catalytic activity and selectivity to aviation fuel owing to the stronger cleavage ability related to the introduction of Ni species. Moreover, aviation fuel selectivity was significantly improved on the hollow hierarchical encapsulated catalysts than their precursors, ascribed to the extended contact time between reactants and active sites. A maximum aviation fuel selectivity of 45% was obtained for the PtNi@HS-1 catalyst at 360 °C under 3 MPa. Furthermore, the PtNi@HS-1 catalyst exhibited superior catalytic stability and selectivity than the PtNi/S-1 catalyst during the stability test. This indicates that the hollow hierarchical encapsulated structure plays crucial roles in enhancing aviation fuel selectivity and catalytic performance.
研究领域:
催化化学
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材料科学
·
能源化工
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DOI
高影响因子
AICHE JOURNAL
·
2026
·
IF 4.4
Qi Liu,Shanlei Han,Dong Xiong,Yuming Li,Qingxin Yang,Dan Zhao,Yuhang Zhong,Shihao Wang,Zhentao Chen,Dmitry E. Doronkin,Laiyong Zhang,Chunming Xu,Guiyuan Jiang
Tuning hydroxyl defects and constructing active sites at the molecular level is critical for rational design of propane dehydrogenation (PDH) catalysts and understanding the structure–activity relationship. For practical application, enhancing catalysts anti-coking performance is equally important. Herein, the simultaneous regulation of hydroxyl nests content and b -axis thickness was achieved by adjusting the urea/SiO 2 ratio during the preparation of Silicalite-1. The propylene formation rate of the catalysts prepared by introducing Zn species showed a linear positive correlation with the hydroxyl nests content, and the coking behavior was governed by the b -axis thickness of the support. The optimized ZnO x /Silicalite-1 exhibited a high propylene space time yield of 2.2 kg h −1 kg cat −1 with propane conversion of 31% at 550°C. This work provides novel insights into PDH catalyst design from both chemistry and chemical engineering views.
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DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
Lei Cai,Xiu Gao,Peihang He,Beining Luo,Xianzai Yan,Zedong Zhang,Wenjun Wang,Guoqiang Wu
To improve the catalytic epoxidation activity of conventional TS-1 zeolite under acid-free conditions, a series of TS-1-supported zinc ( x Zn/TS-1) catalysts were prepared and evaluated in the epoxidation of 1-hexene and methyl oleate (MO) with H 2 O 2 oxidant. The microstructure of x Zn/TS-1 was investigated using various characterization techniques, and the results showed that the introduction of Zn species was not only well dispersed on the surface of TS-1 but also did not disrupt the crystal structure of TS-1 and tetrahedral framework titanium. Furthermore, the Ti-O-Zn structure can be formed between Zn and Ti species through O-atomic coordination, which improves the vulnerability of the Ti-O bond to attack the H 2 O 2 molecule, and ultimately facilitates the epoxidation reaction between 1-hexene and MO. In addition, the 2% Zn/TS-1 catalysts showed optimal conversions of 45.7 % and 75.41 % for 1-hexene and MO, respectively, and exhibited good catalytic stability and regeneration during the epoxidation process.
研究领域:
催化化学
·
材料科学
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产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2017
·
IF 3.615
Chang Wang,Jiaqi Liu,Jiangfeng Yang,Jinping Li
Synthesis of ultra-high silica (SiO 2 /Al 2 O 3 > 1800) MFI type zeolite such as silicalite-1 is still considered to be luxury because of the long synthesis time (5–12 days). Here, this material with a highly uniform mesoporous (20 nm) structure was crystallized in a shorter time (20 h) using a crystal-seeds method when an appropriate amount of potassium fluoride was added. Characterization techniques including XRD , SEM, TEM and liquid nitrogen adsorption provided detailed information on the two kinds of porous structure silicalite-1. Due to the “smooth” adsorption surface of silicalite-1 containing few equilibrium ions, it is ideal for the separation of gas mixtures containing non-polar molecules with similar physical properties. Moreover, the CH 4 , N 2 , CO 2 and C 2 H 6 adsorption properties were also investigated. Microporous silicalite-1 has a high adsorption capacity for CH 4 , N 2 , CO 2 and C 2 H 6 and adsorption selectivity for CH 4 /N 2 , CO 2 /N 2 , CO 2 /CH 4 and C 2 H 6 /CH 4 . Although a lower adsorption capacity was observed for mesoporous silicalite-1, the pore size did not affect the outstanding adsorption selectivity, on the contrary, the selectivity of mesoporous silicalite-1 was improved.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Wangyang Wang,Wei Zhou,Wei Li,Xuewei Xiong,Yuhao Wang,Kang Cheng,Jincan Kang,Qinghong Zhang,Ye Wang
Maximizing the use of palladium without compromises in catalytic activity and stability in the combustion of methane is extremely challenging due to the harsh operation conditions. To achieve this goal, a series of core-shell-structured catalysts with different amounts of palladium nanoparticles confined in hydrophobic silicalite-1 (Pd@S-1) was designed. Unexpectedly, a volcanic trend between catalytic activity and palladium loading was found as the loading increased from 0.3 wt% to 1.6 wt%, among which the 0.6 wt%Pd@S-1 exhibited the highest catalytic activity with a complete combustion temperature of 380 °C. Besides, the 0.6 wt%Pd@S-1 showed an ultrahigh stability in the high temperature applications due to the spatial confinement of palladium inside the rigid zeolite matrix. Moreover, owing to the hydrophobicity of the pure silica zeolite, the Pd@S-1 could selectively hinder the diffusion of water vapor into the palladium sites, leading to the outstanding water-resistance ability.
研究领域:
材料科学
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环境科学
·
化学工程
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产品关联
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2018
·Vol. 34
·期 3
·350-357
·
IF 1.248
Liu Xiaofang,Zeng Shangjing,Wang Runwei,Zhang Zongtao,Qiu Shilun
Hierarchical silicalite-1 zeolites were obtained from the direct conversion of a mixture of ground solid raw materials via a steam-assisted crystallization(SAC) method without involvement of any mesoscale template. Only a trace amount of water was necessary during the crystallization, implying that the amount of water can be dramatically reduced, which still offers easy separation and high yields. The simple procedure involved only grinding and heating, which not only saves resources and energy, but also significantly reduces the discharge of eco-friendly synthesis of zeolites for practical applications. Compared to conventional bulk silicalite-1, the nanosized hierarchical zeolites with MFI structure show enhanced removal capabilities for methylene blue owing to their hierarchical porosity.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Pan Liu,Qin-Hao Zhang,Jian-Qing Zhang,Ji-Ming Hu,Fa-He Cao
A method to quickly prepare highly oriented silicalite-1 zeolite films on different substrates at lower temperature was provided in this work. Compared with the traditional hydrothermal synthesis, rubbing a layer of seed pastes on the pretreated substrate surface in advance and using (NH 4 ) 2 SiF 6 as silicon source for subsequent secondary growth process can effectively reduce the synthesis temperature and shorten the contact time between the substrate and the strong alkaline synthesis solution. The thickness of the zeolite films prepared under three optimal conditions is all around 1 μm and the best contact angle value of 142.5° was achieved for the film prepared at 373 K for 4 h, while this values of the film prepared at 363 K for 6 h and 353 K for 10 h were 97.8° and 41.7°, respectively. The results of SECM showed that the detected localized current value of the film prepared at 353 K for 10 h was similar to that on bare steel after immersion in 0.62 M NaCl solution for 24 h (around 0.4 nA). At the same time, the current value measured under the other two preparation conditions was much higher, suggesting that the corrosion resistance of the film prepared under 353 K was unsatisfactory. In addition, EIS results demonstrated that the corrosion resistance of the films prepared at 363 K for 6 h also decreased significantly after 72 h immersion, while the films prepared at 373 K for 4 h still maintained excellent corrosion resistance and no obvious corrosion products were detected even immersion time up to 720 h. This work provides a new strategy for the application of zeolite in the field of material protection.
研究领域:
材料科学
·
腐蚀与防护
·
化学工程
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2025
·
IF 4.2
Fuwei Gan,Wen Liu,Xinbao Zhang,Maochen Qian,Shaoguo Li,Yuzhong Wang,Junjie Li,Xiangxue Zhu,Xiujie Li
Primary amines, exemplified by n-butylamine, serve as critical intermediates in the synthesis of pharmaceuticals and agrochemicals. Amination of n-butanol with ammonia over supported cobalt catalysts represents a promising synthetic route. To enhance the catalytic performance of Co-based amination catalysts, we reported an acid-treated strategy that allows for precise regulation of cobalt speciation. Among the evaluated supports, silicalite-1 demonstrated superior amination performance, attributed to its unique ability to enhance cobalt dispersion and suppress acid-induced side reactions. Through acid treatment, oversized Co3O4 nanoparticles are selectively removed, thereby preserving highly dispersed cobalt species. Under rigorous reaction conditions (WHSV = 2.5 h-1), the acid-treated catalyst achieved 90% selectivity toward n-butylamine, accompanied by improved stability compared to untreated counterparts. Mechanistic investigations revealed that well-dispersed metallic Co0 nanoparticles promoted selective C-N bond formation via efficient coupling, whereas larger cobalt domains facilitated dehydrogenation-driven carbon deposition pathways. This work establishes a clear structure-performance relationship for cobalt-based amination catalysts, offering a blueprint for sustainable amine production.
研究领域:
催化
·
化学合成
·
材料科学
·
反应工程
·
有机化学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 18
·12837-12849
·
IF 2.993
Han Zongzhuang,Shen Yu,Wang Fumin,Zhang Xubin
Hierarchical titanium silicalite-1 (TS-1) without generated anatase TiO 2 species was synthesized in the presence of polyquaternium-7 (M550) by one-step hydrothermal crystallization method and characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray fluorescence (XRF), Fourier transform infrared spectra, ultraviolet visible spectra, Raman spectroscopy and N 2 adsorption–desorption measurements. The experimental results show that highly porous TS-1 crystals, with pores of ca. 2.6–4.9 nm diameter, are obtained under hydrothermal conditions by using polyquaternium-7 as the mesopore-directing agent. The polyquaternium-7 has a great influence on both the textural properties and the coordination of Ti species in the framework of TS-1. The catalytic properties and recyclability of the prepared mesoporous TS-1 for hydroxylation of phenol with H 2 O 2 have been evaluated, and their activity has been compared with those of TS-1 with only micropores. The great catalytic activity, selectivity and stability of the hierarchical TS-1 as well as the cheap price and environmental-friendly nature of the used mesopore-directing agent allow to consider this hierarchical TS-1 as a promising catalyst for industry application.
研究领域:
材料科学
·
催化化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yong Chen,Xiaoxiao Zhu,Xinping Wang,Yunpeng Su
A facial and cost-effective protocol preparing multi-hollow silicalite-1 (S-1) zeolite was proposed. That is, treating the parent zeolite with tetrapropylammonium hydroxide (TPAOH) solution at low temperature for a period prior to recrystallization. In this protocol, the geometric structure of the product could be highly controlled from hollow to sponge-like multi-hollow configuration, by modulating the period. It was demonstrated that the key role of this step performed before the recrystallization is to create some deep gullies on the parent zeolite that are necessary for constructing the desired multi-hollow structure. This strategy was also succeeded for fast confining single- or bi-metal nanoparticles in much high dispersion within the multi-hollow S-1 without any protective agent addition. It was proved that this protocol is very effective for dispersing Pt within the sponge-like S-1, even for preparing the Pt@S-1 composite with the Pt content as high as 1.67 wt.%. As a specialty of the protocol, it is that, the protocol always gives desired open mesopores to the product material. The Pt@S-1 and PtSn@S-1 exhibited much higher activity for CO oxidation and propane dehydrogenation than the corresponding conventional catalysts.
研究领域:
材料化学
·
纳米催化
·
多孔材料
·
化学工程
·
工业催化
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DOI
高影响因子
Small
·
2024
·
IF 13
Guilin Wei,Linsen Zhou,Xianglin Wang,Ru Tang,Kelin Chen,Junhong Luo,Jiangfeng Song,Yan Shi,Ning Liu,Xingwen Feng
The construction, use, and maintenance of tritium-related equipment will inevitably produce tritium-containing radioactive waste gas, and the production of efficient catalysts for tritium removal remains a difficult problem. Herein, silicalite-1 zeolite with entrapped Pt nanoclusters is skillfully post-oxidized at an appropriate temperature, building highly active Pt─O sites on the nanoclusters to achieve efficient oxidation of hydrogen isotopes at low temperatures. The designed Pt─O sites can directly participate in the oxidation reaction of hydrogen isotopes. Compared to the case without Pt─O sites, the presence of these sites significantly reduces the reaction energy barrier to 0.55 eV, enabling the catalyst to achieve a hydrogen conversion rate of 99% at a low temperature of 40 °C. Specifically, the O atoms consumed by the Pt─O sites in the reaction are replaced by O 2 gas and this cycle repeats, which is consistent with the Mars-van Krevelen (M–K) theory. This ensures efficient catalytic oxidation of hydrogen isotopes, and provides an astonishingly high conversion rate of 99% in the nearly 34 days restart performance test. The results of this study provide insights into the strategic design of efficient catalysts for hydrogen isotope oxidation.
研究领域:
催化化学
·
核能科学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Jian Zhang,Liang Wang,Zhiyi Wu,Hai Wang,Chengtao Wang,Shichao Han,Feng-Shou Xiao
We report the synthesis of Zn/ZSM-5 particles coated with a silicalite-1 zeolite shell (core–shell Zn/ZSM-5@silicalite-1) via grinding of the raw silica source materials with TPAOH and Zn/ZSM-5, followed by solvent-free crystallization at 180 °C for 72 h. The product was well characterized by the XRD patterns, N2 sorption isotherms, SEM images, and TEM images. Because of the core–shell structure, the Zn/ZSM-5@silicalite-1 sample exhibits high selectivities for benzene, toluene, and xylenes in the conversion of methanol, compared with those over ZSM-5 and Zn/ZSM-5 samples. The solvent-free synthesis offers an alternative method for preparing core–shell Zn/ZSM-5@silicalite-1 catalysts.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子