Preparation and Performance of Ni2P/TiO2-Al2O3 for Hydrodenitrogenation

2013 ◽  
Vol 634-638 ◽  
pp. 575-580 ◽  
Author(s):  
Jing Sen Yan ◽  
Hai Yan Wang
Keyword(s):  
Fixed Bed ◽  
Great Influence ◽  
Supported Catalyst ◽  
Active Phase ◽  
Atomic Ratio ◽  
Fixed Bed Reactor ◽  
Tetrabutyl Titanate ◽  
Incipient Wetness Impregnation ◽  
Composite Support ◽  
Al2o3 Composite

A series of TiO2-Al2O3 composite supports were prepared by hydrolysis and deposition of tetrabutyl titanate on macropore Al2O3, and the nickel phosphide catalyst, Ni2P/TiO2-Al2O3, Ni2P/TiO2 and Ni2P/ Al2O3 were prepared by incipient wetness impregnation and in situ H2 reduction method. Their hydrodenitrogenation(HDN) performance were evaluated on a continuous-flow fixed-bed reactor by using quinoline as the model molecules . The results show that the TiO2-Al2O3 composite support still retained the pore properties of macropore Al2O3, and anatase TiO2 were well dispersed on the Al2O3 surface. Different supports had great influence on the reduction behaviour of the oxidic precusors and HDN activity of phosphide catalysts.The main active phase after reduction was Ni2P phase for the TiO2 supportd catalyst, but only Ni12P5 appeared for the TiO2-Al2O3 and Al2O3 supported catalyst. The TiO2-Al2O3 supported catalyst with the Ti /Al atomic ratio of 0.12 exhibited the highest HDN activity among all catalysts.

Synthesis and Characterization of Cu/ZnO Catalyst on Carbon Nanotubes and Al2O3 Supports

2018 ◽  
Vol 916 ◽  
pp. 139-143 ◽  
Author(s):  
Noor Asmawati Mohd Zabidi ◽  
Tuan Syahylah Tuan Sulong ◽  
Sardar Ali
Keyword(s):  
Carbon Nanotubes ◽  
Methyl Formate ◽  
Fixed Bed ◽  
Supported Catalyst ◽  
Hydrogenation Reaction ◽  
Fixed Bed Reactor ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Attractive Option ◽  
Multi Walled Carbon Nanotubes

CO2 conversion into valuable chemicals is an attractive option to deal with the increasing CO2 concentration in the atmosphere. In this study, Cu/ZnO catalyst was synthesized on multi-walled carbon nanotubes (MWCNTs) and Al2O3 supports via incipient wetness impregnation method. The physicochemical properties of the catalysts were investigated using TEM, XRD, N2 adsorption-desorption analysis, H2-TPR and XPS. The performance of the synthesized catalysts in a CO2 hydrogenation reaction was evaluated in a fixed-bed reactor at 503 K, 22.5 bar and H2:CO2 ratio of 3:1. TEM images showed that Cu/ZnO nanoparticles were deposited inside the CNTs as well as on the exterior walls of the CNTs. The average CuO crystallite size on Al2O3 and CNTs supports was 15.7 and 11 nm, repectively. Results of H2-TPR studies showed that the reducibility of the catalyst was improved on the CNTs support. XPS analysis confirmed the presence of Cu2+ in the samples, however, the binding energy of Cu 2p3/2 peak on the Al2O3 support was shifted to higher value compared to that of CNTs support. Products obtained from the CO2 hydrogenation reaction in the presence of these catalyts were methanol, ethanol, methyl formate and methane. The CO2 conversion of around 23% was obtained using both types of catalysts, however, Cu/ZnO on CNTs resulted in higher yield of methyl formate compared to that of Al2O3-supported catalyst.

scholarly journals Tungsten Oxide-Modified SSZ-13 Zeolite as an Efficient Catalyst for Ethylene-To-Propylene Reaction

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 553
Author(s):  
Mansurbek Urol ugli Abdullaev ◽  
Sungjune Lee ◽  
Tae-Wan Kim ◽  
Chul-Ung Kim
Keyword(s):  
Tungsten Oxide ◽  
Fixed Bed ◽  
Acid Sites ◽  
Fixed Bed Reactor ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Efficient Catalyst ◽  
X Ray ◽  
Propylene Selectivity ◽  
Temperature Programmed

Among the zeolitic catalysts for the ethylene-to-propylene (ETP) reaction, the SSZ-13 zeolite shows the highest catalytic activity based on both its suitable pore architecture and tunable acidity. In this study, in order to improve the propylene selectivity further, the surface of the SSZ-13 zeolite was modified with various amounts of tungsten oxide ranging from 1 wt% to 15 wt% via a simple incipient wetness impregnation method. The prepared catalysts were characterized with several analysis techniques, specifically, powder X-ray diffraction (PXRD), Raman spectroscopy, temperature-programmed reduction of hydrogen (H2-TPR), temperature-programmed desorption of ammonia (NH3-TPD), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and N2 sorption, and their catalytic activities were investigated in a fixed-bed reactor system. The tungsten oxide-modified SSZ-13 catalysts demonstrated significantly improved propylene selectivity and yield compared to the parent H-SSZ-13 catalyst. For the tungsten oxide loading, 10 wt% loading showed the highest propylene yield of 64.9 wt%, which was 6.5 wt% higher than the pristine H-SSZ-13 catalyst. This can be related to not only the milder and decreased strong acid sites but also the diffusion restriction of bulky byproducts, as supported by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) observation.

On efficiency of vanadium-oxide promoter in cobalt Fischer – Tropsch catalysts

2021 ◽  
Vol 1 (1-2) ◽  
pp. 15
Author(s):  
Elham Yaghoobpour ◽  
Yahya Zamani ◽  
Saeed Zarrinpashne ◽  
Akbar Zamaniyan
Keyword(s):  
Vanadium Oxide ◽  
Active Sites ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Bet Surface Area ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Fischer Tropsch ◽  
Co Conversion ◽  
Loading Amount

Promoters and their loading amount have crucial roles in cobalt Fischer – Tropsch catalysts. In this regard, the effects of vanadium oxide (V2O5) as a proposed promoter for Co catalyst supported on TiO2 have been investigated. Three catalysts with 0, 1, and 3 wt.% of V2O5 promoter loading are prepared by the incipient wetness impregnation method, and characterized by the BET surface area analyzer, XRD, H2-TPR, and TEM techniques. The fixed-bed reactor was employed for their evaluations. It was found that the catalyst containing 1 wt.% V2O5 has the best performance among the evaluated catalysts, demonstrating remarkable selectivity: 92 % C5+ and 5.7 % CH4, together with preserving the amount of CO conversion compared to the unpromoted catalyst. Furthermore, it is reported that the excess addition of V2O5 promoter (> 1 wt.%) in the introduced catalyst leads to the detrimental effect on the CO conversion and C5+ selectivity, mainly owing to diminished active sites by V2O5 loading.

The Effect of Potassium Carbonate on the Catalytic Properties for Methane Conversion with Ceria

2012 ◽  
Vol 161 ◽  
pp. 194-199
Author(s):  
Yue Juan Duan ◽  
Hua Wang ◽  
Yong Gang Wei ◽  
Kong Zhai Li ◽  
Xing Zhu ◽  
...  
Keyword(s):  
Solid Solution ◽  
Storage Capacity ◽  
Catalytic Properties ◽  
Fixed Bed ◽  
Oxygen Storage Capacity ◽  
Fixed Bed Reactor ◽  
Oxygen Storage ◽  
Incipient Wetness Impregnation ◽  
Solid Reaction ◽  
Gaseous Oxidant

Pure CeO2and a series of (x %) K-CeO2(x=1, 2, 3, 4) catalysts were respectively prepared by the precipitation and incipient wetness impregnation methods, and characterized by means of XRD, BET and H2-TPR techniques. The catalytic activity was investigated by the gas-solid reaction with methane in the absence of gaseous oxidant in a fixed bed reactor at 800 °C. The XRD measurement showed that doping of K2CO3did not change the structure of CeO2with the addition of K2CO3 without formation of Ce-K-O solid solution in these materials. Surface area of catalysts wasSubscript textdecreased with the impregnation amount of K2CO3. Reducibility of catalysts was obviously enhanced by the addition of K2CO3as shown in H2-TPR tests. The catalysts activity tests indicated that adding K2CO3to CeO2could promote the oxygen storage capacity of catalysts. K species in CeO2could affect the CO formation in methane oxidation.

What is the Effect of Promoter Loading on Alkalized Bimetallic Co-Mo Catalyst for Higher Alcohols Synthesis from Syngas?

2019 ◽  
Vol 19 (2) ◽  
pp. 86-94
Author(s):  
R. G. Moqadam ◽  
A. Tavasoli ◽  
M. Salimi
Keyword(s):  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Incipient Wetness Impregnation ◽  
Operating Pressure ◽  
Impregnation Method ◽  
Higher Alcohol Synthesis ◽  
Higher Alcohol ◽  
Alcohol Synthesis ◽  
Higher Alcohols Synthesis ◽  
Methanol Formation

Manganese and nickel co-modified K/Co/MoS2 catalysts supported on graphene were prepared by incipient wetness impregnation method for application in higher alcohol synthesis (HAS). All catalysts were characterized by X-ray diffraction (XRD), nitrogen adsorptiondesorption, temperature-programmed reduction (TPR) and transmission electron microscopy (TEM). The effect of promoters, as well as supports on higher alcohol synthesis production from syngas, was investigated in a fixed bed reactor. The process was performed with an molar ratio H2 : CO = 1 : 1, operating pressure and temperature of 4 MPa and 330 °C, respectively, and gas hourly space velocity (GHSV) 3.84 m3 (STP)/(kgcat.·h) as reaction conditions (STP – standard temperature and pressure). Results originated from practical works showed that the addition of Ni to the graphene-based catalyst increased HAS production and decreased methanol formation. The total alcohols space-time yield (STY) and alcohol selectivity on Ni/Mn/Co/Mo/K/graphene catalyst reached a maximum at 0.41 galc./(gcat.·h) and 63.51 %, respectively, which is higher than the same composition over alumina supported catalyst.

Catalytic Vapor Phase Nitroxidation of p-Xylene: a New Route for Synthesis of Terephthalic Acid and Poly(ethylene Terephthalate)

1992 ◽  
Vol 62 (10) ◽  
pp. 603-607
Author(s):  
Vandana Kala ◽  
R. Prasad ◽  
A. L. Sharma ◽  
J. Mathew
Keyword(s):  
Ethylene Terephthalate ◽  
Oxide Catalyst ◽  
Fixed Bed ◽  
Atomic Ratio ◽  
Fixed Bed Reactor ◽  
Effect Of Temperature ◽  
Poly Ethylene Terephthalate ◽  
Metal Support Interaction ◽  
Metal Support ◽  
Poly Ethylene

We have examined catalytic transformation of p-xylene into terephthalonitrile with nitric oxide (NO) over an aluminium oxide-supported ferric oxide catalyst using a fixed bed reactor in a temperature range of 320-460°c under atmospheric pressure. We achieved a maximum conversion of 80% with an Al2O3:Fe2O3 catalyst having an Al:Fe atomic ratio of nearly 1:1 at a temperature of 360°c with a NO: p-xylene mole ratio of 54.60. We studied the effect of temperature and NO: p-xylene mole ratio on the conversion to terephthalonitrile. Using Mössbauer and IR spectra of the catalysts, we concluded that Al2O3 not only provides a larger surface for the iron oxide catalyst, but also increases its activity by interacting with Fe2O3 and upholds the theory of metal support interaction.

Preparation of TiO2-Al2O3 Support and Hydrodenitrogenation over Ni2P/TiO2-Al2O3 Catalyst

2014 ◽  
Vol 881-883 ◽  
pp. 245-250
Author(s):  
Jing Sen Yan ◽  
Hai Yan Wang ◽  
Feng Wei He
Keyword(s):  
Reduction Method ◽  
Bond Cleavage ◽  
Great Influence ◽  
Active Phase ◽  
Molar Ratio ◽  
Incipient Wetness Impregnation ◽  
Aluminium Nitrate ◽  
Titanium Sulfate ◽  
Co Precipitation

A series of TiO2-Al2O3 composite supports were prepared by co-precipitation of titanium sulfate and aluminium nitrate , and the nickel phosphide catalysts were prepared by incipient wetness impregnation and in situ H2 reduction method. The catalysts were characterized by XRD, N2 adsorption, TPR, TEM and XPS techniques. Their hydrodenitrogenation (HDN) performances were evaluated by using quinoline as model molecules . The results show that TiO2 was evenly dispersed on massive γ-Al2O3 surface. The introduction of TiO2 weakened the strong interaction between Al2O3 and phosphate, and improved the reducibility of the precursors , facilitating to the formation of Ni2P active phase. TiO2 acted as an electronic promoter for the Ni-P catalyst and enhanced both the hydrogenation and C-N bond cleavage activities. Different Ti / Al molar ratio had great influence on HDN activity of the catalyst. The Ni2P /TiO2-Al2O3 with Ti/Al ratio of 1/8, exhibited the highest activity for quinoline HDN.

Hydrogen production by steam reforming of glycerol over Ni/Ce/Cu hydroxyapatite-supported catalysts

2013 ◽  
Vol 67 (7) ◽  
Author(s):  
Lukman Hakim ◽  
Zahira Yaakob ◽  
Manal Ismail ◽  
Wan Daud ◽  
Ratna Sari
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Supported Catalyst ◽  
Fixed Bed Reactor ◽  
Bet Surface Area ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Hydrogen Yield ◽  
Glycerol Conversion

AbstractHydroxyapatite-supported Ni-Ce-Cu catalysts were synthesised and tested to study their potential for use in the steam reforming of glycerol to produce hydrogen. The catalysts were prepared by the deposition-precipitation method with variable nickel, cerium, and copper loadings. The performance of the catalysts was evaluated in terms of hydrogen yield at 600°C in a tubular fixed-bed microreactor. All catalysts were characterised by the BET surface area, XRD, TPR, TEM, and FE-SEM techniques. The reaction time was 240 min in a fixed-bed reactor at 600°C and atmospheric pressure with a water-to-glycerol feed molar ratio of 8: 1. It was found that the Ni-Ce-Cu (3 mass %-7.5 mass %-7.5 mass %) hydroxyapatite-supported catalyst afforded the highest hydrogen yield (57.5 %), with a glycerol conversion rate of 97.3 %. The results indicate that Ni/Ce/Cu/hydroxyapatite has great potential as a catalyst for hydrogen production by steam reforming of glycerol.

scholarly journals Ni–Cu High-Loaded Sol–Gel Catalysts for Dehydrogenation of Liquid Organic Hydrides: Insights into Structural Features and Relationship with Catalytic Activity

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2017
Author(s):  
Yuliya Gulyaeva ◽  
Maria Alekseeva (Bykova) ◽  
Olga Bulavchenko ◽  
Anna Kremneva ◽  
Andrey Saraev ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Sol Gel ◽  
Fixed Bed ◽  
Catalytic Performance ◽  
Structural Features ◽  
Atomic Ratio ◽  
Fixed Bed Reactor ◽  
High Catalytic Activity ◽  
Wide Range ◽  
Structure Reactivity Relationship

The heightened interest in liquid organic hydrogen carriers encourages the development of catalysts suitable for multicycle use. To ensure high catalytic activity and selectivity, the structure–reactivity relationship must be extensively investigated. In this study, high-loaded Ni–Cu catalysts were considered for the dehydrogenation of methylcyclohexane. The highest conversion of 85% and toluene selectivity of 70% were achieved at 325 °C in a fixed-bed reactor using a catalyst with a Cu/Ni atomic ratio of 0.23. To shed light on the relationship between the structural features and catalytic performance, the catalysts were thoroughly studied using a wide range of advanced physicochemical tools. The activity and selectivity of the proposed catalysts are related to the uniformity of Cu distribution and its interaction with Ni via the formation of metallic solid solutions. The method of introduction of copper in the catalyst plays a crucial role in the effectiveness of the interaction between the two metals.

scholarly journals Pembuatan dan uji aktivitas katalis htsc berbasis besi oksida

2018 ◽  
Vol 6 (3) ◽  
pp. 699
Author(s):  
Fitri Rumiani ◽  
S Subagjo
Keyword(s):  
High Temperature ◽  
Surface Area ◽  
Catalyst Surface ◽  
Catalyst Activity ◽  
Nitrate Solution ◽  
Fixed Bed ◽  
Great Influence ◽  
Temperature Shift ◽  
Fixed Bed Reactor ◽  
Preparation Procedure

High temperature shift conversion is a water gas shift reaction using water to produce carbon dioxide and hydrogen in high temperature (370-400oC). The aim of this research is examining the preparation procedure of HTSC catalyst. The catalyst made by Co-precipitation method of Fe and Cr nitrate solution with Na2CO3 as precipitating agent. The specific surface area of catalyst is determined by BET method. The crystal structure was analyzed by XRD method. The catalyst activity was evaluated in the fixed bed reactor on laboratory scale with 370oC and 1 atm. The result shows that the preparation procedure of HTSC ITB catalyst is reproducible. Based on the preparation procedure, calcinations temperature has a great influence to the catalyst surface area. The calcinations temperature at 300oC gave the highest catalyst surface area (198 m2/g), and it is comparable with the surface area claimed by Jennings (200 m2/g). The catalyst has also the highest activity by means of CO conversion resulted by the catalyst activity test (86%) which is larger than commercial catalyst conversion (81%)Keywords : Activity, Catalyst based on Fe/Cr, HTSC, Precipitation Abstrak High temperature shift conversion (HTSC) merupakan reaksi pergeseran CO menggunakan air menjadi CO2 dun H2 yang diselenggarakan pada temperatur tinggi (370-400oC). Penelitian ini bertujuan untuk mendapatkan resep dan prosedur pembuatan katalis HTSC. Katalis dibuat dengan metode kopresipitasi larutan garam nitrat dart Fe dan Cr dengan Na2CO3 sebagai senyawa pengendap. Untuk mengetahui keberhasilan penelitian ini, dilakukan penentuan luas permukaan, struktur kristal, dan aktivitas katalis yang kemudian dibandingkan dengan katalis komersial. Luas permukaan spesiftk diukur menggunakan metode BET, sedangkan struktur kristal dianalisis menggunakan XRD. Uji aktivitas katalis dilakukan dalam reaktor fixed bed skala laboratorium pada 370oC dan 1 atm. Hasil penelt.tian menunjukkan bahwa pelaksanaan prosedur pembuatan katalis HTSC ITB sudah dapat diulangi dengan hasil yang sama (reproducible). Berdasarkan prosedur tersebut, temperatur kalsinasi sangat berpengaruh terhadap lnas permukaan katalis. Dalam rentang temperatur yang dipelajari (300-400oC), kalsinasi pada temperatur 300oC menghasilkan katalis dengan luas permukaan paling tinggi yaitu 192-198 m2/g. Makin tinggi luas permukaan katalis yang dihasilkan, makin tinggi aktivitas katalis tersebut. Katalis dengan luas permukaan 192-198 m2/g menghasilkan aktivitas paling tinggi, konversi CO yang dihasilkan adalah 86 %, sedikit lebih besar dari konversi katalis komersial (81 %).Kata Kunci : Aktivitas, HTSC, Katalis berbasis Fe/Cr, Prespitasi

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