The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Lingjun Chou - One of the best experts on this subject based on the ideXlab platform.
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fabrication of hierarchically porous mgfe2o4 n doped carbon composites for oxidative dehydrogenation of Isobutane
Applied Surface Science, 2020Co-Authors: Baohua Liu, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Abstract MgFe2O4/N-doped carbon (MgFe2O4/N-C) composites with a hierarchically porous structure were successfully synthesized by the one-pot method using MgO as the template and were investigated for the oxidative dehydrogenation of Isobutane with CO2. The catalysts consisting of MgFe2O4 nanoparticles supported on the active carbon (MgFe2O4/AC) and pure MgFe2O4 phase were also prepared for comparison. A series of characterizations with XRD, TEM, XPS and Raman spectroscopy were performed for these materials in order to explore the relationship between the structure and catalytic performance. The high surface area with multiple types of pore structures showed up to 15% iron addition in MgFe2O4/N-C. Furthermore, the effects of acid and base properties on the catalysts were investigated by CO2-TPD and NH3-TPD analyses. Although the coexistence of basic and acidic sites in MgFe2O4/N-C and MgFe2O4/AC samples was observed, the amounts and distribution of the acid and base strengths were very different. The adsorption–desorption of Isobutane or preadsorbed CO2 was utilized to examine the conversion of reactants. It was found that the lower alkali and higher acid contents may have been responsible for the increased catalytic activity. The isobutene formation rate on MgFe2O4/N-C exceeded that obtained when using the active carbon as a support and was 50%.
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fe containing n doped porous carbon for Isobutane dehydrogenation
Microporous and Mesoporous Materials, 2020Co-Authors: Baohua Liu, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Abstract Fe–N–C catalysts were synthesized via high temperature calcining Fe-ZIF-8 (Zeolitic Imidazolate Framework) for catalytic dehydrogenation of Isobutane. The ultimate catalysts are investigated in detail by a series of characterization in order to explore the relationship between the catalyst structure and catalytic performance. XRD, N2 physisorption, TEM and Raman illustrate that Fe doping significantly changes the surface and bulk properties of the catalyst. Increased Fe content causes the decrease of specific surface area and the deposition of Fe2O3 nanoparticles on the catalysts. XPS, ICP-OES and EA show that the surface states and content of N and Fe are also affected with different amounts of Fe. Isobutane and isobutene TPD demonstrate that Fe–N–C catalysts possess reduced adsorption capacity and weaker interaction, thus exhibit lower Isobutane conversion and higher isobutene selectivity compared with N–C catalyst. Moreover, combining other characterizations, such as IR and H2-TPR, both carbonyl group (C O) and Fe2O3 species of the Fe–N–C catalysts contribute to the dehydrogenation activity.
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synthesis and catalytic performance of a dual sites fe zn catalyst based on ordered mesoporous al 2 o 3 for Isobutane dehydrogenation
Catalysis Letters, 2019Co-Authors: Ming Cheng, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Ordered mesoporous Zn/OMA-Fe materials were easily prepared via one pot evaporation induced self-assembly (EISA) method in combination with incipient wetness strategy. Dehydrogenation of Isobutane to isobutene were carried out on these materials, the Isobutane conversion of 50.7% and the yield of 37.8% were obtained over 13Zn/OMA-10Fe catalyst at 580 °C with 300 h−1 GHSV. The synthesized materials with large specific surface areas and uniform pore sizes were characterized by XRD, N2 adsorption–desorption, TEM, XPS, H2-TPR, Mӧssbauer and NH3-TPD. A portion of Fe species were highly dispersed on the support surface and others incorporated into Al2O3 frameworks, Zn species existed in the form of hexagonal ZnO phase. The total acidity of these catalysts was increased by the introduction of Zn, facilitating the conversion of Isobutane. Moreover, the conversion of Fe species might play a major role in improving isobutene selectivity.
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synthesis and catalytic application in Isobutane dehydrogenation of the mesoporous chromia alumina catalysts based on a metal organic framework
Microporous and Mesoporous Materials, 2013Co-Authors: Huahua Zhao, Huanling Song, Lingjun ChouAbstract:The mesoporous chromia/alumina (Cr2O3/Al2O3) catalysts were successfully synthesized using a porous metal-organic framework MIL-101 (Cr3F(H2O)(2)O(BDC)(3)center dot nH(2)O, BDC = 1,4-benzenedicarboxylate) as a molecular host and chromium precursor, inorganic aluminium salt as the aluminium precursor. The aluminium sources had the significant effects on the structure of the products. The formation of alpha-Cr2O3 phase was observed in the mesoporous catalyst (Cr2O3/Al2O3-C) prepared by AlCl3 center dot 6H(2)O, whereas additional chromia alumina solid solution CrxAl2-xO3 phase was produced in the catalyst (Cr2O3/Al2O3-N) using Al(NO3)(3)center dot 9H(2)O as the aluminium precursor. The surface Cr species existed in the Cr6+ and Cr3+ state over the mesoporous catalysts. The Cr species had a strong interaction with the alumina support. Preliminary catalytic studies showed that the Cr2O3/Al2O3-N catalyst exhibited much higher isobutene selectivity and higher stability than the reference catalyst in the Isobutane dehydrogenation. The maintainable dehydrogenation activity during the five dehydrogenation-regeneration cycles indicated high regenerative ability of the catalyst Cr2O3/Al2O3-N. Consequently, this study represents a feasible way toward the facile synthesis of the mesoporous chromia/alumina catalyst. Moreover, this work proposes a novel application of metal-organic framework.
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Isobutane dehydrogenation over the mesoporous cr2o3 al2o3 catalysts synthesized from a metal organic framework mil 101
Applied Catalysis A-general, 2013Co-Authors: Huahua Zhao, Huanling Song, Lingjun ChouAbstract:Abstract The reactivity of Isobutane dehydrogenation over a series of non-ordered mesoporous chromia/alumina (Cr2O3/Al2O3) catalysts with large specific surface area (149.4–381.6 m2 g−1) and high pore volume (0.77–1.24 cm3 g−1), synthesized using a metal-organic framework MIL-101 as a molecular host and chromium precursor, aluminium isopropoxide (Al(i-OC3H7)3) as the aluminium precursor, were studied in detail. The chromium species were highly dispersed over the catalyst with chromia loading up to 10 wt.%. The specific surface area of the catalyst decreased, whereas the amount of surface Cr3+ species and the mole ratio of Cr3+ and Cr6+ species (Cr3+/Cr6+) increased with the increasing chromia loadings (5–25 wt.%) and calcination temperature (500–900 °C), respectively. The addition of potassium to the catalyst system greatly promoted isobutene selectivity and catalyst stability. The catalyst with 1.5 wt.% K2O and 10 wt.% Cr2O3 loadings calcined at 800 °C was found to exhibit the highest Isobutane conversion 60.1% with the isobutene selectivity up to 93.2% among all the catalysts. The maintainable catalytic reactivity demonstrated the high stability of the catalyst in ten dehydrogenation-regeneration cycles. Moreover, it was proposed that the Cr3+ species was mainly the active site and catalytic selectivity was depended on the surface Cr3+/Cr6+ value over the catalyst. The catalyst presented much more stable dehydrogenation activity compared with the conventional catalyst. Consequently, this study presents a feasible way to facile synthesis of the mesoporous MOF-derived Cr2O3/Al2O3 catalysts with high stability and good catalytic reactivity over Isobutane dehydrogenation.
Yoshimori Miyano - One of the best experts on this subject based on the ideXlab platform.
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henry s constants and infinite dilution activity coefficients of propane propene butane Isobutane 1 butene isobutene trans 2 butene and 1 3 butadiene in 2 propanol at 250 330 k
Journal of Chemical & Engineering Data, 2004Co-Authors: Yoshimori MiyanoAbstract:The Henry's constants and the infinite dilution activity coefficients of propane, propene, butane, Isobutane, 1-butene, isobutene, trans-2-butene, and 1,3-butadiene in 2-propanol in the temperature range 250 K to 330 K are measured by a gas stripping method. The rigorous formula for evaluating the Henry's constants from the gas stripping measurements is used for these highly volatile mixtures. The accuracy of the measurements is about 2% for Henry's constants and 3% for the estimated infinite dilution activity coefficients. In the evaluations for the infinite dilution activity coefficients, the nonideality of the solute is not negligible, especially at higher temperatures, and the activity coefficients include the estimation uncertainty of about 1%.
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henry s constants and infinite dilution activity coefficients of propane propene butane isobutene 1 butene Isobutane trans 2 butene and 1 3 butadiene in 1 propanol at t 260 to 340 k
The Journal of Chemical Thermodynamics, 2004Co-Authors: Yoshimori MiyanoAbstract:Abstract The Henry’s constants and the infinite dilution activity coefficients of propane, propene, butane, Isobutane, 1-butene, isobutene, trans-2-butene and 1,3-butadiene in 1-propanol at T=(260 to 340) K are measured by a gas stripping method. The rigorous formula for evaluating the Henry’s constants from the gas stripping measurements is used for these highly volatile mixtures. The accuracy of the measurements is about 2% for Henry’s constants and 3% for the estimated infinite dilution activity coefficients. In the evaluations for the infinite dilution activity coefficients, the nonideality of solute is not negligible especially at higher temperatures and the estimated uncertainty in the infinite dilution activity coefficients include 1% for nonideality.
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henry s constants of butane Isobutane 1 butene and isobutene in methanol at 255 320 k
Fluid Phase Equilibria, 2003Co-Authors: Yoshimori Miyano, Koichiro Nakanishi, Kenji FukuchiAbstract:Abstract The Henry’s constants and the infinite dilution activity coefficients of butane, Isobutane, 1-butene and isobutene in methanol at 255–320 K are measured by a gas stripping method. The rigorous formula for evaluating the Henry’s constants from the gas stripping measurements is proposed for these highly volatile mixtures. By using this formula, a volume effect of vapor phase and the effect of nonideality of fluids are discussed. In the evaluations for activity coefficients the nonideality of solute was not negligible especially at higher temperatures. The values of Henry’s constants of butane are much different from those of Isobutane, while the activity coefficients are not so different to each other. The activity coefficients of butane are about 2.5% greater than those of Isobutane, and those of 1-butene are about 4% greater than those of isobutene.
Huahua Zhao - One of the best experts on this subject based on the ideXlab platform.
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fabrication of hierarchically porous mgfe2o4 n doped carbon composites for oxidative dehydrogenation of Isobutane
Applied Surface Science, 2020Co-Authors: Baohua Liu, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Abstract MgFe2O4/N-doped carbon (MgFe2O4/N-C) composites with a hierarchically porous structure were successfully synthesized by the one-pot method using MgO as the template and were investigated for the oxidative dehydrogenation of Isobutane with CO2. The catalysts consisting of MgFe2O4 nanoparticles supported on the active carbon (MgFe2O4/AC) and pure MgFe2O4 phase were also prepared for comparison. A series of characterizations with XRD, TEM, XPS and Raman spectroscopy were performed for these materials in order to explore the relationship between the structure and catalytic performance. The high surface area with multiple types of pore structures showed up to 15% iron addition in MgFe2O4/N-C. Furthermore, the effects of acid and base properties on the catalysts were investigated by CO2-TPD and NH3-TPD analyses. Although the coexistence of basic and acidic sites in MgFe2O4/N-C and MgFe2O4/AC samples was observed, the amounts and distribution of the acid and base strengths were very different. The adsorption–desorption of Isobutane or preadsorbed CO2 was utilized to examine the conversion of reactants. It was found that the lower alkali and higher acid contents may have been responsible for the increased catalytic activity. The isobutene formation rate on MgFe2O4/N-C exceeded that obtained when using the active carbon as a support and was 50%.
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fe containing n doped porous carbon for Isobutane dehydrogenation
Microporous and Mesoporous Materials, 2020Co-Authors: Baohua Liu, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Abstract Fe–N–C catalysts were synthesized via high temperature calcining Fe-ZIF-8 (Zeolitic Imidazolate Framework) for catalytic dehydrogenation of Isobutane. The ultimate catalysts are investigated in detail by a series of characterization in order to explore the relationship between the catalyst structure and catalytic performance. XRD, N2 physisorption, TEM and Raman illustrate that Fe doping significantly changes the surface and bulk properties of the catalyst. Increased Fe content causes the decrease of specific surface area and the deposition of Fe2O3 nanoparticles on the catalysts. XPS, ICP-OES and EA show that the surface states and content of N and Fe are also affected with different amounts of Fe. Isobutane and isobutene TPD demonstrate that Fe–N–C catalysts possess reduced adsorption capacity and weaker interaction, thus exhibit lower Isobutane conversion and higher isobutene selectivity compared with N–C catalyst. Moreover, combining other characterizations, such as IR and H2-TPR, both carbonyl group (C O) and Fe2O3 species of the Fe–N–C catalysts contribute to the dehydrogenation activity.
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synthesis and catalytic performance of a dual sites fe zn catalyst based on ordered mesoporous al 2 o 3 for Isobutane dehydrogenation
Catalysis Letters, 2019Co-Authors: Ming Cheng, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Ordered mesoporous Zn/OMA-Fe materials were easily prepared via one pot evaporation induced self-assembly (EISA) method in combination with incipient wetness strategy. Dehydrogenation of Isobutane to isobutene were carried out on these materials, the Isobutane conversion of 50.7% and the yield of 37.8% were obtained over 13Zn/OMA-10Fe catalyst at 580 °C with 300 h−1 GHSV. The synthesized materials with large specific surface areas and uniform pore sizes were characterized by XRD, N2 adsorption–desorption, TEM, XPS, H2-TPR, Mӧssbauer and NH3-TPD. A portion of Fe species were highly dispersed on the support surface and others incorporated into Al2O3 frameworks, Zn species existed in the form of hexagonal ZnO phase. The total acidity of these catalysts was increased by the introduction of Zn, facilitating the conversion of Isobutane. Moreover, the conversion of Fe species might play a major role in improving isobutene selectivity.
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synthesis and catalytic application in Isobutane dehydrogenation of the mesoporous chromia alumina catalysts based on a metal organic framework
Microporous and Mesoporous Materials, 2013Co-Authors: Huahua Zhao, Huanling Song, Lingjun ChouAbstract:The mesoporous chromia/alumina (Cr2O3/Al2O3) catalysts were successfully synthesized using a porous metal-organic framework MIL-101 (Cr3F(H2O)(2)O(BDC)(3)center dot nH(2)O, BDC = 1,4-benzenedicarboxylate) as a molecular host and chromium precursor, inorganic aluminium salt as the aluminium precursor. The aluminium sources had the significant effects on the structure of the products. The formation of alpha-Cr2O3 phase was observed in the mesoporous catalyst (Cr2O3/Al2O3-C) prepared by AlCl3 center dot 6H(2)O, whereas additional chromia alumina solid solution CrxAl2-xO3 phase was produced in the catalyst (Cr2O3/Al2O3-N) using Al(NO3)(3)center dot 9H(2)O as the aluminium precursor. The surface Cr species existed in the Cr6+ and Cr3+ state over the mesoporous catalysts. The Cr species had a strong interaction with the alumina support. Preliminary catalytic studies showed that the Cr2O3/Al2O3-N catalyst exhibited much higher isobutene selectivity and higher stability than the reference catalyst in the Isobutane dehydrogenation. The maintainable dehydrogenation activity during the five dehydrogenation-regeneration cycles indicated high regenerative ability of the catalyst Cr2O3/Al2O3-N. Consequently, this study represents a feasible way toward the facile synthesis of the mesoporous chromia/alumina catalyst. Moreover, this work proposes a novel application of metal-organic framework.
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Isobutane dehydrogenation over the mesoporous cr2o3 al2o3 catalysts synthesized from a metal organic framework mil 101
Applied Catalysis A-general, 2013Co-Authors: Huahua Zhao, Huanling Song, Lingjun ChouAbstract:Abstract The reactivity of Isobutane dehydrogenation over a series of non-ordered mesoporous chromia/alumina (Cr2O3/Al2O3) catalysts with large specific surface area (149.4–381.6 m2 g−1) and high pore volume (0.77–1.24 cm3 g−1), synthesized using a metal-organic framework MIL-101 as a molecular host and chromium precursor, aluminium isopropoxide (Al(i-OC3H7)3) as the aluminium precursor, were studied in detail. The chromium species were highly dispersed over the catalyst with chromia loading up to 10 wt.%. The specific surface area of the catalyst decreased, whereas the amount of surface Cr3+ species and the mole ratio of Cr3+ and Cr6+ species (Cr3+/Cr6+) increased with the increasing chromia loadings (5–25 wt.%) and calcination temperature (500–900 °C), respectively. The addition of potassium to the catalyst system greatly promoted isobutene selectivity and catalyst stability. The catalyst with 1.5 wt.% K2O and 10 wt.% Cr2O3 loadings calcined at 800 °C was found to exhibit the highest Isobutane conversion 60.1% with the isobutene selectivity up to 93.2% among all the catalysts. The maintainable catalytic reactivity demonstrated the high stability of the catalyst in ten dehydrogenation-regeneration cycles. Moreover, it was proposed that the Cr3+ species was mainly the active site and catalytic selectivity was depended on the surface Cr3+/Cr6+ value over the catalyst. The catalyst presented much more stable dehydrogenation activity compared with the conventional catalyst. Consequently, this study presents a feasible way to facile synthesis of the mesoporous MOF-derived Cr2O3/Al2O3 catalysts with high stability and good catalytic reactivity over Isobutane dehydrogenation.
Huanling Song - One of the best experts on this subject based on the ideXlab platform.
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fabrication of hierarchically porous mgfe2o4 n doped carbon composites for oxidative dehydrogenation of Isobutane
Applied Surface Science, 2020Co-Authors: Baohua Liu, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Abstract MgFe2O4/N-doped carbon (MgFe2O4/N-C) composites with a hierarchically porous structure were successfully synthesized by the one-pot method using MgO as the template and were investigated for the oxidative dehydrogenation of Isobutane with CO2. The catalysts consisting of MgFe2O4 nanoparticles supported on the active carbon (MgFe2O4/AC) and pure MgFe2O4 phase were also prepared for comparison. A series of characterizations with XRD, TEM, XPS and Raman spectroscopy were performed for these materials in order to explore the relationship between the structure and catalytic performance. The high surface area with multiple types of pore structures showed up to 15% iron addition in MgFe2O4/N-C. Furthermore, the effects of acid and base properties on the catalysts were investigated by CO2-TPD and NH3-TPD analyses. Although the coexistence of basic and acidic sites in MgFe2O4/N-C and MgFe2O4/AC samples was observed, the amounts and distribution of the acid and base strengths were very different. The adsorption–desorption of Isobutane or preadsorbed CO2 was utilized to examine the conversion of reactants. It was found that the lower alkali and higher acid contents may have been responsible for the increased catalytic activity. The isobutene formation rate on MgFe2O4/N-C exceeded that obtained when using the active carbon as a support and was 50%.
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fe containing n doped porous carbon for Isobutane dehydrogenation
Microporous and Mesoporous Materials, 2020Co-Authors: Baohua Liu, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Abstract Fe–N–C catalysts were synthesized via high temperature calcining Fe-ZIF-8 (Zeolitic Imidazolate Framework) for catalytic dehydrogenation of Isobutane. The ultimate catalysts are investigated in detail by a series of characterization in order to explore the relationship between the catalyst structure and catalytic performance. XRD, N2 physisorption, TEM and Raman illustrate that Fe doping significantly changes the surface and bulk properties of the catalyst. Increased Fe content causes the decrease of specific surface area and the deposition of Fe2O3 nanoparticles on the catalysts. XPS, ICP-OES and EA show that the surface states and content of N and Fe are also affected with different amounts of Fe. Isobutane and isobutene TPD demonstrate that Fe–N–C catalysts possess reduced adsorption capacity and weaker interaction, thus exhibit lower Isobutane conversion and higher isobutene selectivity compared with N–C catalyst. Moreover, combining other characterizations, such as IR and H2-TPR, both carbonyl group (C O) and Fe2O3 species of the Fe–N–C catalysts contribute to the dehydrogenation activity.
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synthesis and catalytic performance of a dual sites fe zn catalyst based on ordered mesoporous al 2 o 3 for Isobutane dehydrogenation
Catalysis Letters, 2019Co-Authors: Ming Cheng, Huahua Zhao, Jian Yang, Jun Zhao, Liang Yan, Huanling Song, Lingjun ChouAbstract:Ordered mesoporous Zn/OMA-Fe materials were easily prepared via one pot evaporation induced self-assembly (EISA) method in combination with incipient wetness strategy. Dehydrogenation of Isobutane to isobutene were carried out on these materials, the Isobutane conversion of 50.7% and the yield of 37.8% were obtained over 13Zn/OMA-10Fe catalyst at 580 °C with 300 h−1 GHSV. The synthesized materials with large specific surface areas and uniform pore sizes were characterized by XRD, N2 adsorption–desorption, TEM, XPS, H2-TPR, Mӧssbauer and NH3-TPD. A portion of Fe species were highly dispersed on the support surface and others incorporated into Al2O3 frameworks, Zn species existed in the form of hexagonal ZnO phase. The total acidity of these catalysts was increased by the introduction of Zn, facilitating the conversion of Isobutane. Moreover, the conversion of Fe species might play a major role in improving isobutene selectivity.
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synthesis and catalytic application in Isobutane dehydrogenation of the mesoporous chromia alumina catalysts based on a metal organic framework
Microporous and Mesoporous Materials, 2013Co-Authors: Huahua Zhao, Huanling Song, Lingjun ChouAbstract:The mesoporous chromia/alumina (Cr2O3/Al2O3) catalysts were successfully synthesized using a porous metal-organic framework MIL-101 (Cr3F(H2O)(2)O(BDC)(3)center dot nH(2)O, BDC = 1,4-benzenedicarboxylate) as a molecular host and chromium precursor, inorganic aluminium salt as the aluminium precursor. The aluminium sources had the significant effects on the structure of the products. The formation of alpha-Cr2O3 phase was observed in the mesoporous catalyst (Cr2O3/Al2O3-C) prepared by AlCl3 center dot 6H(2)O, whereas additional chromia alumina solid solution CrxAl2-xO3 phase was produced in the catalyst (Cr2O3/Al2O3-N) using Al(NO3)(3)center dot 9H(2)O as the aluminium precursor. The surface Cr species existed in the Cr6+ and Cr3+ state over the mesoporous catalysts. The Cr species had a strong interaction with the alumina support. Preliminary catalytic studies showed that the Cr2O3/Al2O3-N catalyst exhibited much higher isobutene selectivity and higher stability than the reference catalyst in the Isobutane dehydrogenation. The maintainable dehydrogenation activity during the five dehydrogenation-regeneration cycles indicated high regenerative ability of the catalyst Cr2O3/Al2O3-N. Consequently, this study represents a feasible way toward the facile synthesis of the mesoporous chromia/alumina catalyst. Moreover, this work proposes a novel application of metal-organic framework.
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Isobutane dehydrogenation over the mesoporous cr2o3 al2o3 catalysts synthesized from a metal organic framework mil 101
Applied Catalysis A-general, 2013Co-Authors: Huahua Zhao, Huanling Song, Lingjun ChouAbstract:Abstract The reactivity of Isobutane dehydrogenation over a series of non-ordered mesoporous chromia/alumina (Cr2O3/Al2O3) catalysts with large specific surface area (149.4–381.6 m2 g−1) and high pore volume (0.77–1.24 cm3 g−1), synthesized using a metal-organic framework MIL-101 as a molecular host and chromium precursor, aluminium isopropoxide (Al(i-OC3H7)3) as the aluminium precursor, were studied in detail. The chromium species were highly dispersed over the catalyst with chromia loading up to 10 wt.%. The specific surface area of the catalyst decreased, whereas the amount of surface Cr3+ species and the mole ratio of Cr3+ and Cr6+ species (Cr3+/Cr6+) increased with the increasing chromia loadings (5–25 wt.%) and calcination temperature (500–900 °C), respectively. The addition of potassium to the catalyst system greatly promoted isobutene selectivity and catalyst stability. The catalyst with 1.5 wt.% K2O and 10 wt.% Cr2O3 loadings calcined at 800 °C was found to exhibit the highest Isobutane conversion 60.1% with the isobutene selectivity up to 93.2% among all the catalysts. The maintainable catalytic reactivity demonstrated the high stability of the catalyst in ten dehydrogenation-regeneration cycles. Moreover, it was proposed that the Cr3+ species was mainly the active site and catalytic selectivity was depended on the surface Cr3+/Cr6+ value over the catalyst. The catalyst presented much more stable dehydrogenation activity compared with the conventional catalyst. Consequently, this study presents a feasible way to facile synthesis of the mesoporous MOF-derived Cr2O3/Al2O3 catalysts with high stability and good catalytic reactivity over Isobutane dehydrogenation.
Hui Wang - One of the best experts on this subject based on the ideXlab platform.
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alkylation of Isobutane with butene catalyzed by deep eutectic ionic liquids
Fuel, 2020Co-Authors: Hongyan Wang, Zhimao Zhou, Hui WangAbstract:Abstract The alkylation process of Isobutane with butene is important in the petroleum industry. Ionic liquids (ILs) are considered as attractive alternative catalysts for Isobutane alkylation besides strong liquid acids (H2SO4 or HF) and solid superacids. In this study, ILs based on amides-aluminum chloride (AlCl3) were synthesized and characterized, which exhibited both Lewis and Bronsted acidities. These deep eutectic ILs were found to be efficient catalysts for Isobutane alkylation. The influences of the amide substrate, AlCl3/amide molar ratio, and metal additive on Lewis and Bronsted acidities were observed together with the synergetic effect of Lewis and Bronsted acid sites in the catalytic process. CuCl modified Urea-1.6AlCl3 showed the best catalytic performance. The butene conversion was about 99.9% and C8 selectivity reached 57.6% under optimized reaction conditions (temperature of 15 °C, stirring rate of 1500 rpm, hydrocarbon feeding rate of 300 mL/h, Isobutane/olefin molar ratio of 15:1, and reaction time of 15 min). In addition, Urea-1.6AlCl3-0.13CuCl could be recycled and reused for at least 20 times without obvious loss in catalytic activity.
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Isobutane butene alkylation catalyzed by ionic liquids a more sustainable process for clean oil production
Green Chemistry, 2017Co-Authors: Hui Wang, Xiangzhan Meng, Guoying Zhao, Suojiang ZhangAbstract:The alkylation of Isobutane with butene is an important refining process for the production of a complex mixture of branched alkanes, which is an ideal blending component for gasoline. The current catalysts used in industrial processes are concentrated H2SO4 and HF, which have problems including serious environmental pollution, equipment corrosion, potential safety hazard, high energy consumption in waste acid recycling, etc. Solid catalysts are another type of catalyst for this alkylation; however, they suffer from problems related to rapid deactivation. Ionic liquids (ILs) can be considered as catalysts of the third generation to replace traditional catalysts in Isobutane/butene alkylation to produce clean oil. In this review, alkylation catalyzed by various kinds of acidic ILs, including Lewis acidic ILs (such as chloroaluminate ones) and ILs containing Bronsted acidic functional groups (e.g., –SO3H, [HSO4]−), is reviewed. The currently reported ILs used in the catalysis of Isobutane alkylation and their corresponding catalytic activity are summarized and compared. This will help the readers to know what kinds of ILs are effective for the alkylation of Isobutane with butene and to understand which factors affect the catalytic performance. The advantages of the catalysis of Isobutane/butene alkylation by ILs include tunable acidity of the catalyst by varying the ion structure, limited solubility of the products in the IL phase and therefore easy separation of the alkylate from the catalyst, environmental friendliness, less corrosion of equipment, etc., thus making catalysis by ILs greener. The mechanism and kinetics of the alkylation catalyzed by ILs are discussed. Finally, perspectives and challenges of the Isobutane/butene alkylation catalyzed by ILs are given.
