MICROPOROUS AND MESOPOROUS MATERIALS
·
2016
·
IF 3.349
Lijun Xue,Di Zhang,Yongqiang Xu,Xinmei Liu
γ-Al 2 O 3 without amorphous domains was synthesized by cation-anion double hydrolysis method. The mesopore size in the range of 3.9–8.5 nm was easily controlled by regulating crystallization temperature, solution pH value and the concentration of NaAlO 2 . The introduction of MoO 3 to the γ-Al 2 O 3 via impregnation method can lead to a decrease of specific surface areas, pore sizes and pore volumes of the supports. The less steric hindrance of the larger mesopores (particularly 8.5 nm) exhibits the more Lewis acid sites over the γ-Al 2 O 3 . The MoO 3 /γ-Al 2 O 3 possesses more Bronsted acid sites compared to Lewis. The thiophene compounds can be adsorbed both on the supports and catalysts. The acid sites can facilitate the interaction between the thiophene compounds and catalysts (or supports). The more adsorbed thiophene and dibenzothiophene on the catalysts is attributed to the coordinately unsaturated metal sites and Bronsted acid sites on the surface of the catalysts. Of note is the supports and catalysts with larger pore size (especially 8.5 nm) could promote the adsorption of thiophene compounds. It demonstrates that there is pore confinement effect in the hydrodesulfurization 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
RSC Advances
·
2015
·Vol. 5
·期 127
·104884-104890
·
IF 3.84
Yuan Cai,Huihui Huang,Lei Wang,Xiaojun Zhang,Yuewei Yuan,Rui Li,Hui Wan,Guofeng Guan
Mesoporous γ-AlOOH and γ-Al2O3 with fibrous morphology were successfully synthesized by an ionic liquid ([OMim]Br) assisted low temperature precipitation method using aluminum nitrate and ammonia as aluminum source and precipitant, respectively. The samples were characterized by XRD, TG, FT-IR, TEM, and N2 adsorption–desorption technique. The results showed that the concentration of [OMim]Br had a significant effect on the phase, porous structure, and morphology of γ-Al2O3 due to the strong interactions between [OMim]Br and γ-AlOOH. High purity γ-AlOOH was synthesized at 0.2 M [OMim]Br and γ-Al2O3 with a specific surface area of 243.53 m2 g−1, pore volume of 0.68 cm3 g−1, and average pore size of 11.10 nm was obtained after calcination. Furthermore, the recyclability of [OMim]Br was investigated. The recovery rate of [OMim]Br could reach 95.0 wt%, and the recycled [OMim]Br still had effects on the synthesis of γ-AlOOH and γ-Al2O3.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2023
·
IF 6.2
Tingyu Chen,Shuaiqi Zhao,Jiajin Lin,Yanan Chong,Yifei Li,Yun Zhao,Guangxu Chen,Yongcai Qiu
As a nontoxic and cheap catalyst, the Al 2 O 3 catalyst can be used to catalyze the propane dehydrogenation (PDH) process. However, due to its poor activity, it has been used as a catalyst carrier rather than catalysis. In this work, the experimental results indicate that γ- Al 2 O 3 -(110)-S catalysts can improve the yield of propane dehydrogenation more effectively than γ-Al 2 O 3 -(110) catalyst. We investigate the potential barrier of propane dehydrogenation reaction catalyzed by Al 2 O 3 -(110) under different conditions and found that the substitution of the S atom for partial O atom can modify the acid-base properties of the surface active site of γ-Al 2 O 3 -(110), thus reducing the reaction energy barrier. In particular, the yield of the reaction can be further improved by the active sites of oxygen vacancies generated by removing partial S atoms in γ-Al 2 O 3 -(110)-S, which is consistent with our theoretical calculation results. At the same time, theoretical calculation shows that Cu clusters can effectively remove the S atoms on the surface of γ-Al 2 O 3 -(110)-S and form oxygen vacancies. This strategy provides a new path to form oxygen vacancies on γ-Al 2 O 3 -(110), which opens up a new way for the study of propane dehydrogenation.
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
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 1.6
Tingting Ge,Hui Guo,Yuchao Li,Jinguo Hao,Yanxia Zheng,Lixi Yang,Haofei Huang,Ming Wang,Cuncun Zuo
Effects of trace oxygen on iron sulphides-supported catalysts (FeS x /γ-Al 2 O 3 ) were evaluated through smelter off-gas reduction process for sulphur synthesis. Catalytic performance was evaluated under different oxygen content conditions. The properties of fresh and used catalysts were investigated by means of X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA), X-ray photoelectron spectroscopy (XPS), and elemental analysis and relationships of active phases and activity were analyzed. The relationship between different active crystal crystals (FeS x , FeS 2 , Fe, FeO, γ-Fe 2 O 3 ) and SO 2 /O 2 adsorption and conversion was investigated. The mechanism of oxygen influence on the FeS x /γ-Al 2 O 3 surface was given and the lifetime of the catalyst in the reaction atmosphere close to real smelter off-gas after dust and oxygen removal steps containing trace oxygen (0.5 O 2 v/v.%) was explored.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2021
·
IF 4.158
Lei Dai,Tingting Wang,Boxuan Jin,Na Liu,Yifei Niu,Wenhao Meng,Ziming Gao,Xianwen Wu,Ling Wang,Zhangxing He
Zinc is a widely used anode material for zinc-ion batteries. However, the problems of dendrites and side reactions faced by the metal zinc anode limit its cycle stability and service life. Surface modification is a simple and effective strategy for preparing high-performance anodes. Here, we used a simple method to coat the γ-Al 2 O 3 on surface of metal zinc as an artificial protective layer for the anode/electrolyte. γ-Al 2 O 3 coating can guide the uniform deposition of zinc ions . The coating has good hydrophilicity, which is conducive to accelerate ion transmission. In addition, the importance of controlling the thickness of protective layer on surface of zinc metal anode to obtain good electrochemical performance is emphasized. The appropriate thickness of Al 2 O 3 coating ensures the rapid migration of zinc ions and improves the uniformity of zinc plating/stripping, which is conducive to more uniform zinc nucleation and high-quality deposition. Therefore, the discharge capacity of Zn@Al 2 O 3 -15 full cell at a current density of 0.3 A g −1 is 174.3 mAh g −1 , which is much higher than that of bare zinc cell (71.8 mAh g −1 ). This work has certain reference significance for the development of anode coating strategies in zinc-ion batteries.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Xin Ning,Heming Wang,Ganghua Zhou,Longyun Zhang,Yanju Yang,Jingya Sun,Xiaozhi Wang
Ni catalysts decorated with trace Rh supported on γ-Al2O3 were prepared by the co-impregnation method. To obtain the Ni–Rh nanoparticles with different nanostructures and chemical compositions, bimetallic catalysts with varied Ni/Rh molar ratios were prepared. For comparison, monometallic Ni/γ-Al2O3 and Rh/γ-Al2O3 catalysts were also prepared by the impregnation method. The selective gas phase catalytic hydrodechlorination of 1,2-dichloroethane to ethylene was used to evaluate catalytic performances of the catalysts. The catalysts were characterized by X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, H2 temperature-programmed reduction, transmission electron microscopy–energy-dispersive X-ray, and CO chemisorption. It was found that the introduction of Rh to Ni catalyst facilitated the generation of spillover hydrogen which could enhance the ability of the Ni catalyst for H2 activation. In bimetallic catalysts, there was an intimate interaction between Ni and Rh, and isolated Rh sites were formed due to the dilution effect of Ni. Accordingly, compared with the monometallic Ni catalyst for gas phase catalytic hydrodechlorination of 1,2-dichloroethane, the bimetallic Ni–Rh(800)/γ-Al2O3 catalyst exhibited markedly higher 1,2-dichloroethane conversion (37%) and comparable selectivity to ethylene (95%). The findings in this study indicate that Ni–Rh/γ-Al2O3 with trace Rh can be used as a promising catalyst for highly effective and selective catalytic hydrodechlorination of chlorinated hydrocarbons.
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
Catalysis Science & Technology
·
2019
·Vol. 10
·期 2
·440-449
·
IF 5.726
Pengqi Zhu,Jin Zhang,Jie Wang,Peng Kong,Yunwei Wang,Zhanfeng Zheng
Hydroxyl coordinated ruthenium dispersed on the surface of γ-Al2O3 can be applied to the selective oxidation of amines with light irradiation and an atmospheric pressure of O2 at room temperature. Sunlight is also an effective light source for the selective aerobic oxidation of primary amines to corresponding nitriles. The high photocatalytic activity and selectivity over Ru/γ-Al2O3 originate from the adsorption of amines and imine intermediates on the abundant surface OH groups of the photocatalyst and further formation of Ru–amide species by ligand exchange of adsorbed amines and imine intermediates with adjacent exposed active Ru sites. Light is introduced to the system successfully via the formation of Ru–amide species, which are used as the light absorption sites of the photocatalytic selective oxidation of amines. Primary amines are directly converted to corresponding nitriles via a two-step oxidative dehydrogenation process.
研究领域:
化学工程
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Iranian Chemical Society
·
2016
·Vol. 14
·期 1
·111-119
·
IF 1.3
Yang Xiaomei,Fu Xiaomin,Bu Ningning,Han Li,Wang Jianfeng,Song Chengying,Su Yunlai,Zhou Lipeng,Lu Tianliang
Cu–Ni/γ-Al 2 O 3 bimetallic catalysts were developed for anaerobic dehydrogenation of non-activated primary aliphatic alcohols to aldehydes. Systematic investigation about the promotion effect of nickel on the catalytic performance was carried out. Hydrogenation of C=C bond rather than C=O bond, was significantly improved over Cu–Ni/γ-Al 2 O 3 catalyst by introducing nickel, which interprets the good conversion of primary aliphatic alcohols. This work would contribute to design new catalysts for dehydrogenation of primary aliphatic alcohols.
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
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Jun Wang,Bin Li,Yang Li,Xiaobin Fan,Fengbao Zhang,Guoliang Zhang,Yuanzhi Zhu,Wenchao Peng
In this work, γ-Al2O3-supported CuO (c-CuO/Al2O3) materials are successfully synthesized using a novel impregnation–precipitation–decomposition method. The obtained c-CuO/Al2O3 catalyst shows excellent catalytic activities for bisphenol A (BPA) degradation with sodium persulfate (PDS) as an oxidant. Radical quenching tests and electron paramagnetic resonance (EPR) studies indicate that PDS activation is a combined mechanism involving both free radical and nonfree radical pathways. In a continuous large-scale degradation process, about 1.78 L of 20 ppm BPA can be completely removed within 480 min. Although c-CuO/Al2O3 can be deactivated after several reaction cycles, the catalytic activity can be regenerated after simple aerobic calcination. X-ray photoelectron spectroscopy (XPS) and Raman analysis confirm that the deactivation of c-CuO/Al2O3 should be attributed to the conversion of Cu(II) to Cu(I). The aerobic calcination could oxidize Cu(I) back to Cu(II), thus recovering the catalytic activity. In addition, the density functional technology (DFT) and temperature-programmed oxidation (TPD) results reveal that γ-Al2O3 can not only serve as a carrier to anchor the CuO particles but also can adsorb and activate PDS by introducing more basic sites on the surface. c-CuO/Al2O3 has high activity and can be regenerated easily, thus having great potential applications for wastewater treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
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
NEW JOURNAL OF CHEMISTRY
·
2017
·Vol. 41
·期 21
·13036-13042
·
IF 3.269
Fenfen Lu,Yan Xu,Xia Jiang,Yang Liu,Jiale Huang,Daohua Sun
Low temperature 1,3-butadiene hydrogenation over biosynthesized Pd/γ-Al2O3 catalysts annealed under different atmospheres (H2 and air) was compared in a fixed bed reactor, and the catalysts were prepared using a facile sol-immobilization method. The structural properties of the Pd/γ-Al2O3 catalysts in relation to their activities in 1,3-butadiene hydrogenation were investigated by X-ray photoelectron spectroscopy, X-ray diffraction, hydrogen temperature-programmed reduction, thermogravimetry, transmission electron microscopy, CO chemisorption measurement techniques and Fourier transform infrared spectroscopy. The results of characterization revealed that the calcination atmosphere (H2 and air) exhibited a remarkable impact on the chemical state of Pd species and catalytic activity, and the coexistence of the metallic state and oxidation state of Pd was a key factor for higher catalytic activity and butene selectivity, while the catalyst with the existence of the metallic state only (H2–Pd/γ-Al2O3) showed lower butene selectivity, and the catalyst with the oxidation state alone (air–Pd/γ-Al2O3) hardly showed any activity in 1,3-butadiene hydrogenation. Therefore, the chemical state of Pd played an important role in the 1,3-butadiene hydrogenation reaction.
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
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
·
催化材料
·
可再生资源转化
✓ 已验证
产品关联
DOI
高影响因子