JOURNAL OF THE ENERGY INSTITUTE
·
2024
·
IF 5.6
Bowen Luo,Xiaoxin Chen,Yongxiang Guo,Riyang Shu,Chao Wang,Jianping Liu,Junyao Wang,Zhipeng Tian,Ying Chen
Hydrodeoxygenation (HDO) is a crucial technique for upgrading biomass-derived compounds, playing a significant role in the advancement of sustainable energy technologies. Under harsh reaction conditions, conventional HDO catalysts often suffer from reduced efficiency due to particle aggregation. This study presents a highly efficient Ni/Al 2 O 3 -C catalyst that mitigates this issue by stabilizing Ni metal particles and enhancing metal-support interactions. Characterization of the catalyst was carried out using XRD, TEM, and CO-TPD, which revealed that the incorporation of Al species improved metal dispersion and reduced the size of the Ni particles. Guaiacol, a phenolic compound derived from lignin, was chosen to evaluate the HDO performance under mild conditions. The optimized Ni/3Al 2 O 3 -5C catalyst achieved a guaiacol conversion of 99.9 % with a cyclohexane selectivity of 99.8 % at 210 °C. The outstanding performance is attributed to the high hydrogenation capacity of the small Ni particles and the acid sites on the carbon surface. Metal-support interactions stabilize the Ni particles, preventing leaching and deactivation. The catalyst has also exhibited comparable effectiveness in the HDO of both lignin-derived compounds and lignin-oils, confirming its adaptability across various substrates. The study demonstrates that Al 2 O 3 -C plays a crucial role in enhancing both the structural stability and catalytic efficiency of HDO catalysts, offering a promising approach for upgrading biomass-derived compounds.
研究领域:
催化化学
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生物质能
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 93
·51184-51193
·
IF 3.708
Qing Zhang,Tao Wu,Peng Zhang,Ruijuan Qi,Rong Huang,Xuefeng Song,Lian Gao
Hydrogen reduction of hierarchical spinel intermediates that were synthesized by a facile hydrothermal method results in Ni/γ-Al2O3 nanocomposites with Ni nanoparticles (∼5.5 nm) well dispersed and embedded in nanoflakes of the hollow Al2O3 microspheres. The good dispersion of small metal nanoparticles and strong metal–support interactions that resulted from decomposition of spinel intermediates during reduction are essential for the efficient and sustainable high temperature dry reforming of methane (DRM) catalysis. The high surface area (170 m2 g−1) composite catalysts show coke and sintering resistance in long term DRM catalysis at 750 °C, the highest temperature ever tested for hierarchical nanostructures. Ni loadings and the calcination temperatures of the spinel intermediate are investigated for their effect on the morphology and the catalytic performance of the final catalysts. It is interesting that some initially non-active control catalysts can be activated during long term testing.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2024
·
IF 3.8
Huan Yang,Xu Wang,Haowei Wang,Ya-Dong Xie,An-Hui Lu
Graphical The Sn species doped by coprecipitation with Al precursor introduces additional acidic sites on Sn-doped alumina, which after loading with Pt species exhibits superior reactivity and stability for propane dehydrogenation. Alumina-supported PtSn catalysts have been industrialized as the major catalysts for propane dehydrogenation, where Sn serves as an essential promoter. Herein, we synthesized a variety of Sn-doped alumina supports by regulating the precipitation order of Sn and Al precursors as follows: Sn precursor precipitated before Al, coprecipitated with Al, precipitated immediately after Al, or precipitates after 2 h of Al. The effect of Sn promoter on the surface acidic properties of alumina and, ultimately, on propane dehydrogenation was further investigated. The Sn species introduced by coprecipitation in alumina created additional surface strong acid sites, attributed to more Sn 4+ species on the surface, which are able to remain stable during the subsequent treatment. Consequently, the coprecipitated Sn species in the corresponding catalyst donate more electrons to Pt and reduce the metal particle size. As a result, the catalyst with Pt supported on the coprecipitated support (Sn+Al) exhibits superior initial propane conversion (43.2%) and stability ( k d = 0.035 h −1 ). This study provides new insight into the interaction between the two key components, tin promoter and alumina support, of Pt/Sn-Al 2 O 3 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
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2019
·
IF 3.073
Kai Yang,Yifan Li,Zejun Zhao,Zhongliang Tian,Yanqing Lai
The amorphous porous layered-Al 2 O 3 derived from aluminium fumarate metal-organic frameworks (AlFu MOFs) by roasting at 773 K under air has been applied to remove fluorine ions from industrial ZnSO 4 solution. The amorphous porous layered-Al 2 O 3 was characterized by XRD, SEM and BET. The adsorption experiments were conducted under different conditions, including adsorbent dosage, initial pH, adsorption temperature and adsorption time. And the process of removing fluorine ions is well fitted with the pseudo-second-order kinetic model and Langmuir isotherm model, which is studied by the adsorption kinetics and isotherms. The theoretical maximum adsorption capacity was 12.05 mg g −1 . Moreover, the adsorption mechanism of the amorphous porous layered-Al 2 O 3 was analyzed by SEM-EDS and FTIR. The results indicate that the adsorption process is affected by complexation and ion exchange between fluorine ions and amorphous porous layered-Al 2 O 3 . The regeneration of the amorphous porous layered-Al 2 O 3 shows that the adsorbent could be reused to reduce the production cost.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2016
·
IF 2.101
Dong Feng,Xudong Luo,Guodong Zhang,Zhipeng Xie
In order to determine the relationship between the property of MgOAl 2 O 3 SiO 2 composite ceramics and molar ratios of MgO/Al 2 O 3 , especially the sintering behavior and thermal shock resistance, the MgOAl 2 O 3 SiO 2 composite ceramics were fabricated with micro-size MgO , Al 2 O 3 powder and nano-size SiO 2 as main raw materials. The sample was characterized by phase analysis, densification and thermal shock times. Moreover, field emission scanning electron microscope was also conducted to study microstructure of the samples before and after thermal shock. Effect of different molar ratios of MgO/Al 2 O 3 on the sintering behavior and thermal shock resistance of composite ceramics were investigated. The results showed that the sample possess better sintering behavior and thermal shock resistance with the molar ratio of MgO/Al 2 O 3 equal to 2/1. Grains of periclase and spinel were directly bonded together, resulting in a dense and compact microstructure, and the bulk density of obtained sample reached 3.4 g/cm 3 . The microstructure of sample after thermal shock revealed that the crack propagation path was deflected and bifurcated, the main-crack propagation was restricted and more fracture energy was consumed, the thermal shock resistance of composite ceramics was greatly improved.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2017
·Vol. 147
·期 4
·953-963
·
IF 2.799
Wu Chunyan,Yuan Wenwen,Huang Yi,Xia Yongmei,Yang Huamei,Wang Haijun,Liu Xiang
Abstract A novel heterogeneous catalyst was prepared by immobilizing bifunctional acidic ionic liquid of metal Al substituted (BAIL-Al) onto the surface of magnetic γ-Al 2 O 3 , and characterized by FT-IR, TG, XRD, BET, XPS, VSM, SEM and TEM. The catalytic activity of the prepared solid catalyst was investigated for the conversion of xylose to furfural. On the basis, the effects of temperature, time, amount of catalyst and solvent were studied on the yield of furfural. A furfural yield of 67.5% with 97.3% xylose conversion was obtained from xylose using Fe 3 O 4 @Al 2 O 3 -(BAIL-Al) as the catalyst in DMSO at 140 °C for 3 h. The immobilized catalyst has the features of easily separation and recycling as well as good thermal stability. Thus, the immobilized catalyst can be efficiently and easily recycled at least five times without apparent loss of activity in xylose conversion and furfural yield. Graphical Abstract A novel heterogeneous catalyst was prepared by immobilized bifunctional acidic ionic liquid (BAIL-Al) onto the surface of magnetic γ-Al 2 O 3 , possessing unique physicochemical properties and excellent catalytic activity for xylose transformation have been developed.
研究领域:
化学工程
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催化材料
·
可再生资源转化
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2025
·
IF 4.8
Xiao Yang,Heying Zhao,Aiyong Wang,Wangcheng Zhan,Yanglong Guo,Li Wang,Xuan Tang,Yun Guo
SO 2 in the sintering flue gas severely inhibits the CO oxidation performance of commercial Pt/Al 2 O 3 catalysts. However, the major poisoning mechanism of SO 2 on Pt/Al 2 O 3 in CO oxidation in the presence of H 2 O remains to be elucidated. Here, Pt/Al 2 O 3 was pretreated with different reducing atmospheres at high temperatures. Among these, the catalyst pretreated with a CO atmosphere at 600 °C (denoted as Pt/Al 2 O 3 -CO-600) exhibited superior CO oxidation performance and enhanced sulfur resistance in the presence of both H 2 O and SO 2 . The combination of XPS, HAADF-STEM, TG-MS, SO 2 oxidation test, and in-situ DRIFTS reveal that the Pt species on Pt/Al 2 O 3 -CO-600 transformed from Pt oxide clusters to metallic Pt nanoparticles. This transformation enhanced SO 2 adsorption and reactivity, leading to increased sulfate accumulation. Despite the high SO 2 reactivity and sulfate content, in-situ DRIFTS revealed that the CO reaction of Pt/Al 2 O 3 -CO-600 was less hindered by SO 2 and the sulfated Al 2 O 3 . This is attributed to the high ratio of the under-coordinated (UC) Pt sites in Pt/Al 2 O 3 -CO-600, which promotes the reaction intermediates spillover from Pt site to Al 2 O 3 compared to the Pt/Al 2 O 3 . This phenomenon was positively correlated with the sulfur resistance of reduced catalysts. Accordingly, the UC site contributes to the spillover of sulfate intermediate (H 2 SO 4 ), reducing the CO reactivity loss of Pt/Al 2 O 3 due to the intermediate coverage. This study elucidates that the primary poisoning pathway of Pt/Al 2 O 3 in the presence of H 2 O and SO 2 is the difficulty of sulfate intermediate spillover.
研究领域:
催化化学
·
环境化学
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材料科学
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Guanyu Li,Ruonan Jia,Zheng Liu,Tianfei Qi,Xuefeng Wei,Xin Xu,Linbo Zhang,Liangjun Yin,Li Wang
A short lifetime, low phosphorescence quantum efficiency (PQE), and unstable room-temperature phosphorescence (RTP) in oxidants and solvents are the core problems in the development of carbon dot (CD)-based RTP materials for anticounterfeiting applications. Herein, a series of CDs/Al2O3 nanocomposites with excitation-dependent RTP properties were fabricated by a sol–gel process followed by high-temperature treatment. The crystalline structure and rigid Al–O network of the Al2O3 matrix could readily benefit the stabilization of the triplet excited state of CDs. The Al–O–C interactions between the CDs and Al2O3 favor the facilitation of intersystem crossing (ISC) to effectively populate triplet excitons, which contributes to the RTP with a low energy gap. As a result, an ultralong lifetime of up to 1.4 s (observed by the naked eye for 22 s) and a high PQE of 12.78% were achieved by CDs/Al2O3-500 and CDs/Al2O3-300, respectively. The results demonstrated that the oxidants, polar solvents, and strong acids and alkalis almost had no effect on the RTP emission of the CDs/Al2O3 nanocomposites. Taking advantage of the ultralong phosphorescence afterglow, excitation-dependent multicolor RTP emission, and excellent stability, graphics of the Eight Trigrams were present for advanced anticounterfeiting via time-resolved luminescence imaging based on different CDs/Al2O3 nanocomposites.
研究领域:
材料科学
·
纳米技术
·
光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 13
·4412-4423
·
IF 5.721
Qiang Liu,Zhenbo Zhao,Masahiko Arai,Chao Zhang,Ke Liu,Ruhui Shi,Peixuan Wu,Zhuangqing Wang,Weiwei Lin,Haiyang Cheng,Fengyu Zhao
The transformation of γ-valerolactone (GVL) into 1,4-pentanediol (1,4-PDO) and 2-methyltetra-hydrofuran (2-MTHF) in the presence of H2, one of the useful biomass conversion and utilization processes, was investigated with monometallic Cu/Al2O3 and bimetallic ZnCu/Al2O3 catalysts. A 10 wt% Cu-loaded monometallic catalyst produced 1,4-PDO and 2-MTHF in comparable quantities at a medium conversion (∼50%). When Zn was added in a range of Zn/Cu molar ratios of up to 2, in contrast, the catalysts yielded 1,4-PDO in a high selectivity of about 97% at low and high conversion levels. In addition, the 1,4-PDO selectivity over the ZnCu/Al2O3 catalysts remained almost unchanged during recycled runs. That is, the addition of Zn to Cu/Al2O3 switched the product selectivity and improved the catalyst stability and reusability. Furthermore, the physicochemical properties of the catalysts were characterized by several methods including XRD, TEM, TPR, XPS, FTIR of adsorbed pyridine, and so on. On the basis of those results, the relationships between the catalytic performance (activity, selectivity, and reusability) and the catalyst structural features were discussed.
研究领域:
催化化学
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生物质转化
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 45
·46705
·
IF 1.901
Dapeng Gu,Longxiao Zhang,Suwen Chen,Kefeng Song,Shouyao Liu
The filling combination of polytetrafluoroethylene (PTFE)/Cu/Al 2 O 3 filled poly(methyl methacrylate) (PMMA) based composites aiming at low friction and wear is optimized based on L 9 (3 4 ) by Taguchi method. The worn morphologies of PMMA based composites are analyzed by scanning electron microscopy (SEM). The PTFE transfer film and the wear debris on the steel ball surface are analyzed by SEM and X-ray spectroscopy. It is observed that the friction and wear of PMMA can be obviously decreased by filling with PTFE, Cu, and Al 2 O 3 . PTFE has the most significant but Cu has the negligibly smallest contribution on both the friction coefficient and the wear rate. The lower friction coefficient (<0.2) appears by the combination of the mass ratio of PTFE larger than about 4.5% and the mass ratio of Al 2 O 3 lower than ∼7.5%. The lower wear rate (<5 × 10 −5 mm 3 /Nm) appears by the combination of the mass ratio of PTFE larger than about 5% and the mass ratio of Al 2 O 3 lower than ∼8%, but it does not include that PTFE is greater than about 8.5% and Al 2 O 3 is less than about 1.5%. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46705.
研究领域:
材料科学
·
机械工程
✓ 已验证
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2019
·Vol. 33
·期 11
·e5208
·
IF 3.259
Baowei Wang,Chengyu Wang,Wenxian Yu
Mo 2 C/Al 2 O 3 catalyst was prepared by the impregnation method with urotropine and ammonium paramolybdate. The catalytic effect of Mo 2 C as a typical transition-metal carbide in sulfur-resistant methanation was studied. The catalysts prepared were characterized by N 2 adsorption–desorption, X-ray diffraction, transmission electron microscopy, H 2 -temperature-programmed reduction, and Raman spectra, with the results confirming the formation of β-molybdenum carbide on the surface of the catalysts. Studies on catalysts with different loading doses indicate that the optimal loading of Mo 2 C/Al 2 O 3 is about 15 wt.%, which enables CO conversion rate of up to 47%, with methane selectivity of up to 53%. This work further explored the effect of different concentrations of H 2 S in the raw gas on the performance of the catalyst, with the results showing that high concentration of H 2 S (>1500 ppm) can lead to sulfuration of active species on the catalyst, while resulting in a decrease in the catalytic activity.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2018
·Vol. 10
·期 24
·5637-5648
·
IF 4.674
Zhiquan Hou,Yuxi Liu,Jiguang Deng,Yue Lu,Shaohua Xie,Xiuzhong Fang,Hongxing Dai
Graphical Effective synergy : The Pd−GaO x /Al 2 O 3 catalysts are prepared via the oxidative transformation of intermetallic Pd 5 Ga 3 nanocrystals supported on Al 2 O 3 . A synergistic effect between palladium and gallium oxide via formation of a bi-functional active Pd−O−Ga phase is observed, resulting in a highly active and exceptionally stable catalyst that can markedly suppress the sintering of noble metals under harsh conditions. Surface oxygen vacancies and the surface Pd−O−Ga phase are the catalytically active sites. Catalytic combustion of methane is widely used in industrial and transportation activities. The commonly used Pd-based catalysts, however, are easily deactivated under hydrothermal conditions. In this work, we adopted a novel strategy to prepare a GaO x -doped Pd/Al 2 O 3 catalyst via the oxidative transformation of intermetallic Pd 5 Ga 3 nanocrystals supported on γ -Al 2 O 3 . We observed a synergistic effect between palladium and gallium oxide via formation of a bi-functional active Pd−O−Ga phase, resulting in a highly active and exceptionally stable catalyst that could markedly suppress the sintering of noble metals under harsh conditions (hydrothermal treatment at 750 °C). Moreover, the presence of a large amount of surface oxygen vacancies and the surface Pd−O−Ga phase could promote methane combustion over the catalysts. It is believed that such a novel dual-metal catalyst is promising in practical applications for methane combustion.
研究领域:
催化化学
·
环境科学
·
材料科学
✓ 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）