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Galina A. Bukhtiyarova - One of the best experts on this subject based on the ideXlab platform.
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Support Effect on the Performance of Ni2P Catalysts in the Hydrodeoxygenation of Methyl Palmitate
Catalysts, 2018Co-Authors: Irina V. Deliy, Evgeny Yu. Gerasimov, Ivan V. Shamanaev, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Ilya V. Yakovlev, Olga B. Lapina, Galina A. BukhtiyarovaAbstract:The effect of support nature, SiO2 and γ-Al2O3, on physicochemical and catalytic properties of nickel phosphide catalysts in Methyl Palmitate hydrodeoxygenation (HDO) has been considered. Firstly, alumina-supported nickel phosphide catalysts prepared by temperature-programmed reduction method starting from different precursors (phosphate–Ni(NO3)2 and (NH4)2HPO4 or phosphite–Ni(OH)2 and H3PO3) were compared using elemental analysis, N2 physisorption, H2-TPR, XRD, TEM, NH3-TPD, 27Al and 31P MAS NMR techniques and catalytic experiments. The mixture of nickel phosphide phases was produced from phosphate precursor on alumina while using of phosphite precursor provides Ni2P formation with the higher activity in Methyl Palmitate HDO. Besides, the comparative study of the performances of Ni2P/SiO2 and Ni2P/Al2O3 catalysts demonstrates the apparent superiority of alumina-supported Ni2P in the Methyl Palmitate hydrodeoxygenation. Considering the tentative scheme of Methyl Palmitate transformation, we proposed that cooperation of Ni2P and acid sites on the surface of alumina provides the enhanced activity of alumina-supported Ni2P through the acceleration of acid-catalysed hydrolysis.
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Synergetic Effect of Ni2P/SiO2 and γ-Al2O3 Physical Mixture in Hydrodeoxygenation of Methyl Palmitate
Catalysts, 2017Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Galina A. BukhtiyarovaAbstract:The Ni2P/SiO2 catalyst, which was prepared by in situ temperature-programmed reduction and in the mixture with the inert (SiC, SiO2) or acidic (γ-Al2O3) material was studied in Methyl Palmitate hydrodeoxygenation (HDO). Methyl Palmitate HDO was carried out at temperatures of 270–330 °C, H2/feed volume ratio of 600 Nm3/m3, and H2 pressure of 3.0 MPa. Ni2P/SiO2 catalyst, diluted with γ-Al2O3 showed a higher activity than Ni2P/SiO2 catalyst diluted with SiC or SiO2. The conversion of Methyl Palmitate increased significantly in the presence of γ-Al2O3 most probably due to the acceleration of the acid-catalyzed reaction of ester hydrolysis. The synergism of Ni2P/SiO2 and γ-Al2O3 in Methyl Palmitate HDO can be explained by the cooperation of the metal sites of Ni2P/SiO2 and the acid sites of γ-Al2O3 in consecutive metal-catalyzed and acid-catalyzed reactions of HDO. The obtained results let us conclude that the balancing of metal and acid sites plays an important role in the development of the efficient catalyst for the HDO of fatty acid esters over supported phosphide catalysts.
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HDO of Methyl Palmitate over Silica-Supported Ni Phosphides: Insight into Ni/P Effect
Catalysts, 2017Co-Authors: Irina V. Deliy, Evgeny Yu. Gerasimov, Ivan V. Shamanaev, Pavel V. Aleksandrov, Vera P. Pakharukova, Ilya V. Yakovlev, Olga B. Lapina, Galina A. BukhtiyarovaAbstract:Two sets of silica-supported nickel phosphide catalysts with a nickel content of about 2.5 and 10 wt % and Ni/P molar ratio 2/1, 1/1 and 1/2 in each set, were prepared by way of a temperature-programmed reduction method using (Ni(CH3COO)2) and ((NH4)2HPO4) as a precursor. The NixPy/SiO2 catalysts were characterized using chemical analysis N2 physisorption, XRD, TEM, 31P MAS NMR. Methyl Palmitate hydrodeoxygenation (HDO) was performed in a trickle-bed reactor at 3 MPa and 290 °C with LHSV ranging from 0.3 to 16 h−1. The Ni/P ratio was found to affect the nickel phosphide phase composition, POx groups content and catalytic properties in Methyl Palmitate HDO with the TOF increased along with a decline of Ni/P ratio and a growth of POx groups’ content. Taking into account the possible routes of Methyl Palmitate conversion (metal-catalyzed hydrogenolysis or acid-catalyzed hydrolysis), we proposed that the enhancement of acid POx groups’ content with the Ni/P ratio decrease provides an enhancement of the rate of Methyl Palmitate conversion through the acceleration of acid-catalyzed hydrolysis.
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Effect of precursor on the catalytic properties of Ni2P/SiO2 in Methyl Palmitate hydrodeoxygenation
RSC Advances, 2016Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Olga B. Lapina, Artem B. Ayupov, Andrey S. Andreev, Galina A. BukhtiyarovaAbstract:The effect of phosphorus precursor on the physicochemical and catalytic properties of silica-supported nickel phosphide catalysts in the hydrodeoxygenation (HDO) of aliphatic model compound Methyl Palmitate (C15H31COOCH3) has been considered. Nickel acetate (Ni(OAc)2) and diammonium hydrogen phosphate ((NH4)2HPO4) (phosphate precursor) or nickel hydroxide (Ni(OH)2) and phosphorous acid (H3PO3) (phosphite precursor) have been used for the catalyst preparation by incipient wetness impregnation of SiO2 with an aqueous solution of the precursors, followed by temperature-programmed reduction in hydrogen flow. Chemical analysis (ICP-AES), H2-TPR, NH3-TPD, 31P MAS NMR, XRD, and TEM have been employed for the characterization of the catalysts. The optimal reduction parameters of the silica-supported nickel phosphide catalysts have been found for the phosphate and phosphite precursors in terms of their activity in Methyl Palmitate HDO. The Ni2P/SiO2 catalysts prepared by the phosphite method have shown higher catalytic activity in comparison with the Ni2P/SiO2 catalysts prepared by the phosphate method. The activity has been shown to depend on the catalyst handling after reduction: in situ reduced catalysts demonstrate higher conversion of Methyl Palmitate than the samples exposed to the reduction, passivation and re-reduction steps.
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Hydrodeoxygenation of Methyl Palmitate over sulfided Mo/Al2O3, CoMo/Al2O3and NiMo/Al2O3catalysts
RSC Adv., 2014Co-Authors: Irina V. Deliy, Evgenia N. Vlasova, Alexey L. Nuzhdin, Evgeny Yu. Gerasimov, Galina A. BukhtiyarovaAbstract:The catalytic properties of sulfided Mo/Al2O3, CoMo/Al2O3 and NiMo/Al2O3 catalysts in the hydrodeoxygenation of Methyl Palmitate as a model compound for triglyceride feedstock were studied at 300 °C and 3.5 MPa in the batch reactor using n-tetradecane, m-xylene and hydrotreated straight-run gas oil (HT-SRGO). The comparison of catalyst's performance in n-tetradecane allowed us to see that the sulfided Mo/Al2O3, CoMo/Al2O3 and NiMo/Al2O3 catalysts revealed the same rate of the Methyl Palmitate conversion but the rate of the intermediate oxygenates conversion decreased in order: CoMoS/Al2O3 > NiMoS/Al2O3 > MoS2/Al2O3. A mixture of linear saturated and unsaturated C15 and C16 hydrocarbons was produced when the oxygenates were fully consumed. The main products obtained over the Mo/Al2O3 and CoMo/Al2O3 catalysts were C16 hydrocarbons (C16/C15 – 16.1 and 2.79, respectively); however, C15 hydrocarbons were preferentially formed over the NiMo/Al2O3 catalyst (C16/C15 – 0.65), highlighting the different contributions of the hydrodeoxygenation (HDO) and decarboxylation/decarbonylation (DeCOx) pathways during the hydroconversion of Methyl Palmitate over these catalysts. Investigating the solvent's influence on the activity of the CoMo/Al2O3 and NiMo/Al2O3 catalysts in the Methyl Palmitate HDO revealed that the reaction rate was decreased in the following order: n-tetradecane > HT-SRGO > m-xylene. The aromatic compounds did not retard the Methyl Palmitate transformation, but inhibited the conversion of the intermediate oxygenates. Decreased C16/C15 ratios were observed over both catalysts when m-xylene was used as the reaction medium instead of n-tetradecane.
Irina V. Deliy - One of the best experts on this subject based on the ideXlab platform.
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Support Effect on the Performance of Ni2P Catalysts in the Hydrodeoxygenation of Methyl Palmitate
Catalysts, 2018Co-Authors: Irina V. Deliy, Evgeny Yu. Gerasimov, Ivan V. Shamanaev, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Ilya V. Yakovlev, Olga B. Lapina, Galina A. BukhtiyarovaAbstract:The effect of support nature, SiO2 and γ-Al2O3, on physicochemical and catalytic properties of nickel phosphide catalysts in Methyl Palmitate hydrodeoxygenation (HDO) has been considered. Firstly, alumina-supported nickel phosphide catalysts prepared by temperature-programmed reduction method starting from different precursors (phosphate–Ni(NO3)2 and (NH4)2HPO4 or phosphite–Ni(OH)2 and H3PO3) were compared using elemental analysis, N2 physisorption, H2-TPR, XRD, TEM, NH3-TPD, 27Al and 31P MAS NMR techniques and catalytic experiments. The mixture of nickel phosphide phases was produced from phosphate precursor on alumina while using of phosphite precursor provides Ni2P formation with the higher activity in Methyl Palmitate HDO. Besides, the comparative study of the performances of Ni2P/SiO2 and Ni2P/Al2O3 catalysts demonstrates the apparent superiority of alumina-supported Ni2P in the Methyl Palmitate hydrodeoxygenation. Considering the tentative scheme of Methyl Palmitate transformation, we proposed that cooperation of Ni2P and acid sites on the surface of alumina provides the enhanced activity of alumina-supported Ni2P through the acceleration of acid-catalysed hydrolysis.
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Synergetic Effect of Ni2P/SiO2 and γ-Al2O3 Physical Mixture in Hydrodeoxygenation of Methyl Palmitate
Catalysts, 2017Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Galina A. BukhtiyarovaAbstract:The Ni2P/SiO2 catalyst, which was prepared by in situ temperature-programmed reduction and in the mixture with the inert (SiC, SiO2) or acidic (γ-Al2O3) material was studied in Methyl Palmitate hydrodeoxygenation (HDO). Methyl Palmitate HDO was carried out at temperatures of 270–330 °C, H2/feed volume ratio of 600 Nm3/m3, and H2 pressure of 3.0 MPa. Ni2P/SiO2 catalyst, diluted with γ-Al2O3 showed a higher activity than Ni2P/SiO2 catalyst diluted with SiC or SiO2. The conversion of Methyl Palmitate increased significantly in the presence of γ-Al2O3 most probably due to the acceleration of the acid-catalyzed reaction of ester hydrolysis. The synergism of Ni2P/SiO2 and γ-Al2O3 in Methyl Palmitate HDO can be explained by the cooperation of the metal sites of Ni2P/SiO2 and the acid sites of γ-Al2O3 in consecutive metal-catalyzed and acid-catalyzed reactions of HDO. The obtained results let us conclude that the balancing of metal and acid sites plays an important role in the development of the efficient catalyst for the HDO of fatty acid esters over supported phosphide catalysts.
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synergetic effect of ni2p sio2 and γ al2o3 physical mixture in hydrodeoxygenation of Methyl Palmitate
Catalysts, 2017Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, G A BukhtiyarovaAbstract:The Ni2P/SiO2 catalyst, which was prepared by in situ temperature-programmed reduction and in the mixture with the inert (SiC, SiO2) or acidic (γ-Al2O3) material was studied in Methyl Palmitate hydrodeoxygenation (HDO). Methyl Palmitate HDO was carried out at temperatures of 270–330 °C, H2/feed volume ratio of 600 Nm3/m3, and H2 pressure of 3.0 MPa. Ni2P/SiO2 catalyst, diluted with γ-Al2O3 showed a higher activity than Ni2P/SiO2 catalyst diluted with SiC or SiO2. The conversion of Methyl Palmitate increased significantly in the presence of γ-Al2O3 most probably due to the acceleration of the acid-catalyzed reaction of ester hydrolysis. The synergism of Ni2P/SiO2 and γ-Al2O3 in Methyl Palmitate HDO can be explained by the cooperation of the metal sites of Ni2P/SiO2 and the acid sites of γ-Al2O3 in consecutive metal-catalyzed and acid-catalyzed reactions of HDO. The obtained results let us conclude that the balancing of metal and acid sites plays an important role in the development of the efficient catalyst for the HDO of fatty acid esters over supported phosphide catalysts.
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HDO of Methyl Palmitate over Silica-Supported Ni Phosphides: Insight into Ni/P Effect
Catalysts, 2017Co-Authors: Irina V. Deliy, Evgeny Yu. Gerasimov, Ivan V. Shamanaev, Pavel V. Aleksandrov, Vera P. Pakharukova, Ilya V. Yakovlev, Olga B. Lapina, Galina A. BukhtiyarovaAbstract:Two sets of silica-supported nickel phosphide catalysts with a nickel content of about 2.5 and 10 wt % and Ni/P molar ratio 2/1, 1/1 and 1/2 in each set, were prepared by way of a temperature-programmed reduction method using (Ni(CH3COO)2) and ((NH4)2HPO4) as a precursor. The NixPy/SiO2 catalysts were characterized using chemical analysis N2 physisorption, XRD, TEM, 31P MAS NMR. Methyl Palmitate hydrodeoxygenation (HDO) was performed in a trickle-bed reactor at 3 MPa and 290 °C with LHSV ranging from 0.3 to 16 h−1. The Ni/P ratio was found to affect the nickel phosphide phase composition, POx groups content and catalytic properties in Methyl Palmitate HDO with the TOF increased along with a decline of Ni/P ratio and a growth of POx groups’ content. Taking into account the possible routes of Methyl Palmitate conversion (metal-catalyzed hydrogenolysis or acid-catalyzed hydrolysis), we proposed that the enhancement of acid POx groups’ content with the Ni/P ratio decrease provides an enhancement of the rate of Methyl Palmitate conversion through the acceleration of acid-catalyzed hydrolysis.
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effect of precursor on the catalytic properties of ni2p sio2 in Methyl Palmitate hydrodeoxygenation
RSC Advances, 2016Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Olga B. Lapina, Artem B. Ayupov, Andrey S. Andreev, G A BukhtiyarovaAbstract:The effect of phosphorus precursor on the physicochemical and catalytic properties of silica-supported nickel phosphide catalysts in the hydrodeoxygenation (HDO) of aliphatic model compound Methyl Palmitate (C15H31COOCH3) has been considered. Nickel acetate (Ni(OAc)2) and diammonium hydrogen phosphate ((NH4)2HPO4) (phosphate precursor) or nickel hydroxide (Ni(OH)2) and phosphorous acid (H3PO3) (phosphite precursor) have been used for the catalyst preparation by incipient wetness impregnation of SiO2 with an aqueous solution of the precursors, followed by temperature-programmed reduction in hydrogen flow. Chemical analysis (ICP-AES), H2-TPR, NH3-TPD, 31P MAS NMR, XRD, and TEM have been employed for the characterization of the catalysts. The optimal reduction parameters of the silica-supported nickel phosphide catalysts have been found for the phosphate and phosphite precursors in terms of their activity in Methyl Palmitate HDO. The Ni2P/SiO2 catalysts prepared by the phosphite method have shown higher catalytic activity in comparison with the Ni2P/SiO2 catalysts prepared by the phosphate method. The activity has been shown to depend on the catalyst handling after reduction: in situ reduced catalysts demonstrate higher conversion of Methyl Palmitate than the samples exposed to the reduction, passivation and re-reduction steps.
Qingxin Guan - One of the best experts on this subject based on the ideXlab platform.
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catalytic performance and deoxygenation path of Methyl Palmitate on ni2p sio2 synthesized using the thermal decomposition of nickel hypophosphite
RSC Advances, 2016Co-Authors: Qingxin Guan, Fei HanAbstract:In this paper, the catalytic performance and deoxygenation path of Methyl Palmitate on Ni2P/SiO2 catalysts were systematically studied in a continuous flow fixed-bed reactor. A series of Ni2P/SiO2 catalysts (with different molar ratios of P/Ni and Ni2P loadings) were synthesized at 300 °C using the thermal decomposition of nickel hypophosphite. The increased molar ratio of P/Ni generates phosphate-rich nickel phosphide catalysts and increasing conversion. Interestingly, Ni2P/SiO2 showed significantly higher conversion of Methyl Palmitate in comparison with Ni/SiO2. Furthermore, an activation temperature higher than 500 °C would significantly reduce the catalytic activity, as a result of the sintering of Ni2P. The pressure in a range of 3.0 to 0.5 MPa almost has no effect on the deoxygenation of Methyl Palmitate, but significantly affects the reaction path and product distribution. Finally, a possible deoxygenation path over Ni2P/SiO2 was proposed based on a GC-MS investigation.
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Hydrodeoxygenation of Methyl Palmitate over MCM-41 supported nickel phosphide catalysts
Catalysis Today, 2016Co-Authors: Qingxin Guan, Fanfan Wan, Fei Han, Zihe LiuAbstract:Abstract In this paper, bulk and MCM-41-supported Ni 2 P catalysts were synthesized by the one-step direct reduction of metal phosphate precursors. The role of cations and anions in the synthesis of Ni 2 P was studied. Catalytic properties for the hydrodeoxygenation (HDO) of Methyl Palmitate were first investigated in a continuous-flow fixed-bed microreactor. The resulting catalysts were characterized using XRD, TEM, BET, XPS, and carbon monoxide chemisorption. Results indicated that Ni 2 P can be synthesized at 600 °C from its phosphate precursors with a mole ratio of Ni/P = 2/1. Based on the analytical result of GC-MS, we propose a possible HDO reaction mechanism for the HDO of Methyl Palmitate on MCM-41-supported nickel phosphide catalysts.
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Catalytic performance and deoxygenation path of Methyl Palmitate on Ni2P/SiO2 synthesized using the thermal decomposition of nickel hypophosphite
RSC Advances, 2016Co-Authors: Qingxin Guan, Fei HanAbstract:In this paper, the catalytic performance and deoxygenation path of Methyl Palmitate on Ni2P/SiO2 catalysts were systematically studied in a continuous flow fixed-bed reactor. A series of Ni2P/SiO2 catalysts (with different molar ratios of P/Ni and Ni2P loadings) were synthesized at 300 °C using the thermal decomposition of nickel hypophosphite. The increased molar ratio of P/Ni generates phosphate-rich nickel phosphide catalysts and increasing conversion. Interestingly, Ni2P/SiO2 showed significantly higher conversion of Methyl Palmitate in comparison with Ni/SiO2. Furthermore, an activation temperature higher than 500 °C would significantly reduce the catalytic activity, as a result of the sintering of Ni2P. The pressure in a range of 3.0 to 0.5 MPa almost has no effect on the deoxygenation of Methyl Palmitate, but significantly affects the reaction path and product distribution. Finally, a possible deoxygenation path over Ni2P/SiO2 was proposed based on a GC-MS investigation.
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synthesis of bulk and supported nickel phosphide using microwave radiation for hydrodeoxygenation of Methyl Palmitate
RSC Advances, 2015Co-Authors: Qingxin Guan, Yinan XueAbstract:In this paper, we proposed a novel method for preparing bulk and supported Ni2P catalysts under mild conditions. Ni2P and Ni2P/SiO2 were synthesized from nickel hypophosphite precursors at 230 °C for 5 min using a CEM Discover microwave reactor, and the initial reaction temperature is about 202 °C. The catalysts were characterized using XRD, TEM, SEM, XPS, BET, carbon monoxide chemisorption, and the catalytic performance was tested for hydrodeoxygenation (HDO) of Methyl Palmitate in a fixed-bed reactor. Interestingly, microwave irradiation does not result in sintering of Ni2P particles. The principal products of the HDO reaction for both catalysts are pentadecane and hexadecane. Isomerization products were not detected, and other by-products content is very low (<1%). The HDO results demonstrate that the catalyst prepared using a microwave has better activity than that prepared using calcination.
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Deoxygenation of Methyl Palmitate over SiO2-supported nickel phosphide catalysts: effects of pressure and kinetic investigation
RSC Advances, 2015Co-Authors: Fei Han, Qingxin GuanAbstract:In this paper, a series of Ni2P/SiO2 catalysts was synthesized using the thermal decomposition of hypophosphite precursors. The resulting catalysts were characterized using XRD, TEM, CO pulse adsorption, atomic adsorption spectroscopy and NH3-TPD, and the catalytic properties were investigated for deoxygenation of Methyl Palmitate at different pressures in a fixed-bed reactor. The results indicate that the catalysts at 1.0 MPa and 3.0 MPa have similar activity, and lower pressure is in favour of direct deoxygenation of Methyl Palmitate. Pseudo first order kinetics were employed to describe the reaction to understand the effect of pressure and temperature and active energy at different reaction pressures was calculated. According to the active energy, the scission of the C–O bond is more difficult than the C–C, and the HDO route was favored at higher reaction pressure and temperature.
Evgeny Yu. Gerasimov - One of the best experts on this subject based on the ideXlab platform.
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Support Effect on the Performance of Ni2P Catalysts in the Hydrodeoxygenation of Methyl Palmitate
Catalysts, 2018Co-Authors: Irina V. Deliy, Evgeny Yu. Gerasimov, Ivan V. Shamanaev, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Ilya V. Yakovlev, Olga B. Lapina, Galina A. BukhtiyarovaAbstract:The effect of support nature, SiO2 and γ-Al2O3, on physicochemical and catalytic properties of nickel phosphide catalysts in Methyl Palmitate hydrodeoxygenation (HDO) has been considered. Firstly, alumina-supported nickel phosphide catalysts prepared by temperature-programmed reduction method starting from different precursors (phosphate–Ni(NO3)2 and (NH4)2HPO4 or phosphite–Ni(OH)2 and H3PO3) were compared using elemental analysis, N2 physisorption, H2-TPR, XRD, TEM, NH3-TPD, 27Al and 31P MAS NMR techniques and catalytic experiments. The mixture of nickel phosphide phases was produced from phosphate precursor on alumina while using of phosphite precursor provides Ni2P formation with the higher activity in Methyl Palmitate HDO. Besides, the comparative study of the performances of Ni2P/SiO2 and Ni2P/Al2O3 catalysts demonstrates the apparent superiority of alumina-supported Ni2P in the Methyl Palmitate hydrodeoxygenation. Considering the tentative scheme of Methyl Palmitate transformation, we proposed that cooperation of Ni2P and acid sites on the surface of alumina provides the enhanced activity of alumina-supported Ni2P through the acceleration of acid-catalysed hydrolysis.
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Synergetic Effect of Ni2P/SiO2 and γ-Al2O3 Physical Mixture in Hydrodeoxygenation of Methyl Palmitate
Catalysts, 2017Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Galina A. BukhtiyarovaAbstract:The Ni2P/SiO2 catalyst, which was prepared by in situ temperature-programmed reduction and in the mixture with the inert (SiC, SiO2) or acidic (γ-Al2O3) material was studied in Methyl Palmitate hydrodeoxygenation (HDO). Methyl Palmitate HDO was carried out at temperatures of 270–330 °C, H2/feed volume ratio of 600 Nm3/m3, and H2 pressure of 3.0 MPa. Ni2P/SiO2 catalyst, diluted with γ-Al2O3 showed a higher activity than Ni2P/SiO2 catalyst diluted with SiC or SiO2. The conversion of Methyl Palmitate increased significantly in the presence of γ-Al2O3 most probably due to the acceleration of the acid-catalyzed reaction of ester hydrolysis. The synergism of Ni2P/SiO2 and γ-Al2O3 in Methyl Palmitate HDO can be explained by the cooperation of the metal sites of Ni2P/SiO2 and the acid sites of γ-Al2O3 in consecutive metal-catalyzed and acid-catalyzed reactions of HDO. The obtained results let us conclude that the balancing of metal and acid sites plays an important role in the development of the efficient catalyst for the HDO of fatty acid esters over supported phosphide catalysts.
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synergetic effect of ni2p sio2 and γ al2o3 physical mixture in hydrodeoxygenation of Methyl Palmitate
Catalysts, 2017Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, G A BukhtiyarovaAbstract:The Ni2P/SiO2 catalyst, which was prepared by in situ temperature-programmed reduction and in the mixture with the inert (SiC, SiO2) or acidic (γ-Al2O3) material was studied in Methyl Palmitate hydrodeoxygenation (HDO). Methyl Palmitate HDO was carried out at temperatures of 270–330 °C, H2/feed volume ratio of 600 Nm3/m3, and H2 pressure of 3.0 MPa. Ni2P/SiO2 catalyst, diluted with γ-Al2O3 showed a higher activity than Ni2P/SiO2 catalyst diluted with SiC or SiO2. The conversion of Methyl Palmitate increased significantly in the presence of γ-Al2O3 most probably due to the acceleration of the acid-catalyzed reaction of ester hydrolysis. The synergism of Ni2P/SiO2 and γ-Al2O3 in Methyl Palmitate HDO can be explained by the cooperation of the metal sites of Ni2P/SiO2 and the acid sites of γ-Al2O3 in consecutive metal-catalyzed and acid-catalyzed reactions of HDO. The obtained results let us conclude that the balancing of metal and acid sites plays an important role in the development of the efficient catalyst for the HDO of fatty acid esters over supported phosphide catalysts.
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HDO of Methyl Palmitate over Silica-Supported Ni Phosphides: Insight into Ni/P Effect
Catalysts, 2017Co-Authors: Irina V. Deliy, Evgeny Yu. Gerasimov, Ivan V. Shamanaev, Pavel V. Aleksandrov, Vera P. Pakharukova, Ilya V. Yakovlev, Olga B. Lapina, Galina A. BukhtiyarovaAbstract:Two sets of silica-supported nickel phosphide catalysts with a nickel content of about 2.5 and 10 wt % and Ni/P molar ratio 2/1, 1/1 and 1/2 in each set, were prepared by way of a temperature-programmed reduction method using (Ni(CH3COO)2) and ((NH4)2HPO4) as a precursor. The NixPy/SiO2 catalysts were characterized using chemical analysis N2 physisorption, XRD, TEM, 31P MAS NMR. Methyl Palmitate hydrodeoxygenation (HDO) was performed in a trickle-bed reactor at 3 MPa and 290 °C with LHSV ranging from 0.3 to 16 h−1. The Ni/P ratio was found to affect the nickel phosphide phase composition, POx groups content and catalytic properties in Methyl Palmitate HDO with the TOF increased along with a decline of Ni/P ratio and a growth of POx groups’ content. Taking into account the possible routes of Methyl Palmitate conversion (metal-catalyzed hydrogenolysis or acid-catalyzed hydrolysis), we proposed that the enhancement of acid POx groups’ content with the Ni/P ratio decrease provides an enhancement of the rate of Methyl Palmitate conversion through the acceleration of acid-catalyzed hydrolysis.
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effect of precursor on the catalytic properties of ni2p sio2 in Methyl Palmitate hydrodeoxygenation
RSC Advances, 2016Co-Authors: Ivan V. Shamanaev, Irina V. Deliy, Evgeny Yu. Gerasimov, Pavel V. Aleksandrov, Vera P. Pakharukova, Evgeny Kodenev, Olga B. Lapina, Artem B. Ayupov, Andrey S. Andreev, G A BukhtiyarovaAbstract:The effect of phosphorus precursor on the physicochemical and catalytic properties of silica-supported nickel phosphide catalysts in the hydrodeoxygenation (HDO) of aliphatic model compound Methyl Palmitate (C15H31COOCH3) has been considered. Nickel acetate (Ni(OAc)2) and diammonium hydrogen phosphate ((NH4)2HPO4) (phosphate precursor) or nickel hydroxide (Ni(OH)2) and phosphorous acid (H3PO3) (phosphite precursor) have been used for the catalyst preparation by incipient wetness impregnation of SiO2 with an aqueous solution of the precursors, followed by temperature-programmed reduction in hydrogen flow. Chemical analysis (ICP-AES), H2-TPR, NH3-TPD, 31P MAS NMR, XRD, and TEM have been employed for the characterization of the catalysts. The optimal reduction parameters of the silica-supported nickel phosphide catalysts have been found for the phosphate and phosphite precursors in terms of their activity in Methyl Palmitate HDO. The Ni2P/SiO2 catalysts prepared by the phosphite method have shown higher catalytic activity in comparison with the Ni2P/SiO2 catalysts prepared by the phosphate method. The activity has been shown to depend on the catalyst handling after reduction: in situ reduced catalysts demonstrate higher conversion of Methyl Palmitate than the samples exposed to the reduction, passivation and re-reduction steps.
Fei Han - One of the best experts on this subject based on the ideXlab platform.
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catalytic performance and deoxygenation path of Methyl Palmitate on ni2p sio2 synthesized using the thermal decomposition of nickel hypophosphite
RSC Advances, 2016Co-Authors: Qingxin Guan, Fei HanAbstract:In this paper, the catalytic performance and deoxygenation path of Methyl Palmitate on Ni2P/SiO2 catalysts were systematically studied in a continuous flow fixed-bed reactor. A series of Ni2P/SiO2 catalysts (with different molar ratios of P/Ni and Ni2P loadings) were synthesized at 300 °C using the thermal decomposition of nickel hypophosphite. The increased molar ratio of P/Ni generates phosphate-rich nickel phosphide catalysts and increasing conversion. Interestingly, Ni2P/SiO2 showed significantly higher conversion of Methyl Palmitate in comparison with Ni/SiO2. Furthermore, an activation temperature higher than 500 °C would significantly reduce the catalytic activity, as a result of the sintering of Ni2P. The pressure in a range of 3.0 to 0.5 MPa almost has no effect on the deoxygenation of Methyl Palmitate, but significantly affects the reaction path and product distribution. Finally, a possible deoxygenation path over Ni2P/SiO2 was proposed based on a GC-MS investigation.
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Hydrodeoxygenation of Methyl Palmitate over MCM-41 supported nickel phosphide catalysts
Catalysis Today, 2016Co-Authors: Qingxin Guan, Fanfan Wan, Fei Han, Zihe LiuAbstract:Abstract In this paper, bulk and MCM-41-supported Ni 2 P catalysts were synthesized by the one-step direct reduction of metal phosphate precursors. The role of cations and anions in the synthesis of Ni 2 P was studied. Catalytic properties for the hydrodeoxygenation (HDO) of Methyl Palmitate were first investigated in a continuous-flow fixed-bed microreactor. The resulting catalysts were characterized using XRD, TEM, BET, XPS, and carbon monoxide chemisorption. Results indicated that Ni 2 P can be synthesized at 600 °C from its phosphate precursors with a mole ratio of Ni/P = 2/1. Based on the analytical result of GC-MS, we propose a possible HDO reaction mechanism for the HDO of Methyl Palmitate on MCM-41-supported nickel phosphide catalysts.
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Catalytic performance and deoxygenation path of Methyl Palmitate on Ni2P/SiO2 synthesized using the thermal decomposition of nickel hypophosphite
RSC Advances, 2016Co-Authors: Qingxin Guan, Fei HanAbstract:In this paper, the catalytic performance and deoxygenation path of Methyl Palmitate on Ni2P/SiO2 catalysts were systematically studied in a continuous flow fixed-bed reactor. A series of Ni2P/SiO2 catalysts (with different molar ratios of P/Ni and Ni2P loadings) were synthesized at 300 °C using the thermal decomposition of nickel hypophosphite. The increased molar ratio of P/Ni generates phosphate-rich nickel phosphide catalysts and increasing conversion. Interestingly, Ni2P/SiO2 showed significantly higher conversion of Methyl Palmitate in comparison with Ni/SiO2. Furthermore, an activation temperature higher than 500 °C would significantly reduce the catalytic activity, as a result of the sintering of Ni2P. The pressure in a range of 3.0 to 0.5 MPa almost has no effect on the deoxygenation of Methyl Palmitate, but significantly affects the reaction path and product distribution. Finally, a possible deoxygenation path over Ni2P/SiO2 was proposed based on a GC-MS investigation.
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Deoxygenation of Methyl Palmitate over SiO2-supported nickel phosphide catalysts: effects of pressure and kinetic investigation
RSC Advances, 2015Co-Authors: Fei Han, Qingxin GuanAbstract:In this paper, a series of Ni2P/SiO2 catalysts was synthesized using the thermal decomposition of hypophosphite precursors. The resulting catalysts were characterized using XRD, TEM, CO pulse adsorption, atomic adsorption spectroscopy and NH3-TPD, and the catalytic properties were investigated for deoxygenation of Methyl Palmitate at different pressures in a fixed-bed reactor. The results indicate that the catalysts at 1.0 MPa and 3.0 MPa have similar activity, and lower pressure is in favour of direct deoxygenation of Methyl Palmitate. Pseudo first order kinetics were employed to describe the reaction to understand the effect of pressure and temperature and active energy at different reaction pressures was calculated. According to the active energy, the scission of the C–O bond is more difficult than the C–C, and the HDO route was favored at higher reaction pressure and temperature.