The Influence of the Cobalt-Containing Component of the Composite Catalyst on the One-Stage Process for Synthesis of Liquid Hydrocarbons from CO and H2

2019 ◽  
Vol 19 (3) ◽  
pp. 178-186
Author(s):  
R. E. Yakovenko ◽  
I. N. Zubkov ◽  
G. B. Narochnyi ◽  
S. V. Nekroenko ◽  
A. P. Savost’yanov
Keyword(s):  
Catalyst Deactivation ◽  
Molecular Mass Distribution ◽  
Fixed Bed ◽  
Gasoline Fraction ◽  
Fixed Bed Reactor ◽  
Composite Catalyst ◽  
Liquid Hydrocarbons ◽  
Stage Process ◽  
The One

The influence of the cobalt-containing component (Co-Al2O3/SiO2, Co-Re/Al2O3 and Co-Re/TiO2) of a composite catalyst was studied in the Fischer – Tropsch combined process for synthesis and hydrotransformation of hydrocarbons. A flow fixed-bed reactor was used for characterization of the catalytic properties at 2 MPa, flow rate 1000 h–1, 240–280 °C for 40–90 hours of continuous operation. The highest productivity and selectivity to C5+ hydrocarbons equal to 106 kg/(m3 cat·ч) and 67.1 %, respectively, was characteristic of the composite catalyst Co-Al2O3/SiO2(35%)/ZSM-5(30%)/Al2O3(30%) at 240 °C. The comparable activities were observed with the catalysts Co-Re/Al2O3 and Co-Al2O3/SiO2 but the former provided the formation of unsaturated hydrocarbons in a lower proportion in the products. The use of the Co-Re/TiO2 catalyst at elevated temperature (up to 280 °C) allowed the molecular mass distribution of the products to be shifted towards the formation of the gasoline fraction. The rate of the catalyst deactivation was established to increase in the series Co-Al2O3/SiO2 > Co-Re/Al2O3 > Co-Re/TiO2.

Synthesis and characterization of cobalt-doped molybdenum carbides produced in a fixed bed reactor

2018 ◽  
Vol 44 (16) ◽  
pp. 20551-20555 ◽  
Author(s):  
S.L.A. Dantas ◽  
A.L. Lopes-Moriyama ◽  
M.S. Sena ◽  
C.P. Souza
Keyword(s):  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Synthesis And Characterization ◽  
Molybdenum Carbides

scholarly journals Analysis and Model-Based Description of the Total Process of Periodic Deactivation and Regeneration of a VOx Catalyst for Selective Dehydrogenation of Propane

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1374
Author(s):  
Andreas Brune ◽  
Andreas Seidel-Morgenstern ◽  
Christof Hamel
Keyword(s):  
Catalyst Deactivation ◽  
Process Development ◽  
Coke Formation ◽  
Fixed Bed ◽  
Reaction Network ◽  
Fixed Bed Reactor ◽  
Side Reactions ◽  
Model Based ◽  
Total Process

This study intends to provide insights into various aspects related to the reaction kinetics of the VOx catalyzed propane dehydrogenation including main and side reactions and, in particular, catalyst deactivation and regeneration, which can be hardly found in combination in current literature. To kinetically describe the complex reaction network, a reduced model was fitted to lab scale experiments performed in a fixed bed reactor. Additionally, thermogravimetric analysis (TGA) was applied to investigate the coking behavior of the catalyst under defined conditions considering propane and propene as precursors for coke formation. Propene was identified to be the main coke precursor, which agrees with results of experiments using a segmented fixed bed reactor (FBR). A mechanistic multilayer-monolayer coke growth model was developed to mathematically describe the catalyst coking. Samples from long-term deactivation experiments in an FBR were used for regeneration experiments with oxygen to gasify the coke deposits in a TGA. A power law approach was able to describe the regeneration behavior well. Finally, the results of periodic experiments consisting of several deactivation and regeneration cycles verified the long-term stability of the catalyst and confirmed the validity of the derived and parametrized kinetic models for deactivation and regeneration, which will allow model-based process development and optimization.

Synthesis, Structural and Electrochemical Characterization of Honeycomb Supported Pt-Pd-Rh Composite Catalyst for the Decomposition of Gaseous Ammonia to Nitrogen

2011 ◽  
Vol 214 ◽  
pp. 21-25 ◽  
Author(s):  
Chang Mao Hung
Keyword(s):  
Fixed Bed ◽  
Ceramic Materials ◽  
Composite Catalyst ◽  
Gaseous Ammonia ◽  
Incipient Wetness Impregnation ◽  
Selective Catalytic Oxidation ◽  
High Initial Concentration ◽  
Nh3 Oxidation ◽  
Cellular Ceramic

The behavior of the ammonia (NH3) oxidation was by selective catalytic oxidation (SCO) over a honeycomb supported Pt-Pd-Rh composite catalyst in a tubular fixed-bed flow quartz reactor (TFBR) at 673 K. A honeycomb Pt-Pd-Rh composite catalyst was prepared by incipient wetness impregnation with aqueous solutions of H2PtCl6, Pd(NO3)3 and Rh(NO3)3 that were coated on cordierite cellular ceramic materials. The catalysts surface properties were characterized using OM. The experimental results show that contaminants crystal aggregation phases and washcoat loss from high initial concentration of NH3 may be responsible for the deactivation of the catalysts. In addition, the catalytic redox behavior was determined by cyclic voltammetric (CV), which showed that the catalytic behavior is related to the metal oxide properties of the catalyst.

scholarly journals Optimization and Characterization of Bio-oil Produced from Rice Husk Using Surface Response Methodology

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Ige Ayodeji Rapheal ◽  
Elinge Cosmos Moki ◽  
Aliyu Muhammad ◽  
Gwani Mohammed ◽  
Lawal Hassan Gusau
Keyword(s):  
Particle Size ◽  
Rice Husk ◽  
Fixed Bed ◽  
Production Optimization ◽  
Fixed Bed Reactor ◽  
Pyrolysis Process ◽  
Surface Response Methodology ◽  
Chemical Efficiency ◽  
Bio Oil

AbstractThe study depicts the production, optimization and characterization of bio-oil from pyrolyzed rice husk using a fabricated fixed bed reactor. The pyrolysis process was conducted with bio-oil response, bio-char response and non-condensable gases response as products. The effect of pyrolysis variables were observed by the production of the bio-oil as the response. Sixty runs of pyrolysis experiments were suggested by Box Benkhen design indicated optimum pyrolysis conditions at particle size of 2.03mm mesh, reaction time of 81.80 mins and temperature of 650oC for rice husk. The maximum bio-oil yield was obtained with 38.39% at optimum condition of the variables. The bio-oil sample obtained had better performance compared with ASTM standard. Such a determination would contribute so immensely to a significant comprehension of the chemical efficiency of the pyrolysis reaction.

scholarly journals AKTIVITAS DAN SELEKTIVITAS KATALIS Ni/H5NZA TERHADAP HIDRORENGKAH METIL OLEAT MENJADI SENYAWA HIDROKARBON FRAKSI PENDEK

2018 ◽  
Vol 3 (1) ◽  
pp. 58
Author(s):  
Ratno Budiyanto ◽  
Donatus Setyawan ◽  
Novita Andarini
Keyword(s):  
Fixed Bed ◽  
Gravimetric Method ◽  
Fixed Bed Reactor ◽  
Stream Velocity ◽  
Impregnation Method ◽  
Wet Impregnation ◽  
Hydrocracking Process ◽  
Short Fraction

It has conducted on the activity and selectivity of Ni/H5NZA catalyst toward the hydrocracking of oleat methyl catalytic becomes short fraction hydrocarbon compounds with the variation of Ni concentration such as 1%, 2% and 3% (% w/w) for oleat methyl catalytic hydrocracking becomes short fraction hydrocarbon compounds (C5-C11 hydrocarbon). The catalyst is prepared by wet impregnation method, then followed by calcinations at 500oC, oxidation at 400oC and reduction at 500oC, each of them are followed by a stream of nitrogen, oxygen and hydrogen with ± 5mL/second in stream velocity. The characterization of catalyst includes the determination of Si/Al ratio, Ni metal that were impregnated by using AAS instrument, and the acid determination by using gravimetric method. The hydrocracking process is done in flow-fixed bed reactor at 500oC; the catalyst are heated at first and followed by the reactants which are heated in pyrolysis reactor up to it change into vapor, then they are moved into the hydrocracking reactor. The liquid from hydrocracking process is collected and analyzed by using Gas of Chromatography (GC) and Gas of Chromatography-Mass spectrometer (GC-MS). The characterization results showed in general that Si/Al ratio decreases after being impregnated by Ni metal. The amount of Ni metal almost reach a half of early Ni concentration which is impregnated. On the other hands, the acid amount of catalyst after being impregnated by Ni metal rise higher than those before being impregnated by Ni metal. The research showed that the activity and selectivity of Ni-2%/H5NZA catalyst is better in hydrocracking hydrocarbon compounds which are shorter. The activity of Ni-2%/H5NZA catalyst reaches 91.3041%. Meanwhile the selectivity is more selective in creating the hydrocarbon compounds with C5-C11 chain and more lead to the formation of alkane and alkene. Keywords: methyloleate, catalyst, Ni/H5NZ,hydrocracking

scholarly journals Hydrogen Generation from Catalytic Steam Reforming Bio-Oil Model Compound—Acetic Acid Employing Ni/attapulgite Catalysts Prepared with Different Preparation Methods

2016 ◽  
Author(s):  
Yishuang Wang ◽  
Mingqiang Chen ◽  
Tian Liang ◽  
Jie Yang ◽  
Zhonglian Yang ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Steam Reforming ◽  
Catalyst Deactivation ◽  
Hydrogen Generation ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Precipitation Method ◽  
Impregnation Method ◽  
Bio Oil ◽  
Catalytic Steam Reforming

In this research, catalytic steam reforming acetic acid derived from the aqueous portion of bio-oil for hydrogen production was investigated by using different Ni/ATC (Attapulgite Clay) catalysts prepared by precipitation, impregnation and mechanical blending methods. The fresh and reduced catalysts were characterized by XRD, N2 adsorption-desorption, TEM and H2-TPR. The comprehensive results demonstrated that the interaction between active metallic Ni and ATC carrier was significantly improved in Ni/ATC catalyst prepared by precipitation method, and in which the mean Ni particle size was the smallest (~13 nm) resulted in the highest metal dispersion (7.5%). The catalytic performance of the three catalysts was evaluated through the process of steam reforming of acetic acid in a fixed-bed reactor under atmospheric pressure at two different temperatures, such as 550 ℃ and 650 ℃. Results showed that the Ni/ATC (PM-N/ATC) prepared by precipitation method, achieved the highest H2 yield of ~82% and little lower acetic acid conversion efficiency of ~85% than that (~95%) of Ni/ATC (IM-NATC) prepared by impregnation method. In addition, the deactivation catalysts after reaction for 4 h were analyzed by XRD, TGA-DTG and TEM, which demonstrated that the catalyst deactivation was not caused by the amount of carbon deposition, but owed to the significant agglomeration and sintering of Ni particles in the carrier.

scholarly journals In-site Preparation and Characterization Catalytic- Composite Used for Plastic Waste Degradation to Fuel.

2021 ◽  
Author(s):  
Ameen Abdelrahman ◽  
Asmaa S. Hamouda ◽  
A.H. Zaki
Keyword(s):  
Fixed Bed ◽  
Plastic Waste ◽  
High Density ◽  
Fixed Bed Reactor ◽  
Composite Catalyst ◽  
X Ray Diffraction ◽  
Spectroscopic Analyses ◽  
Transmission Electron ◽  
Waste Degradation ◽  
Gasification Reaction

Abstract In order to get renewable energy from plastic waste, it should find a pathway or create a new composite that is thermally stable, non-toxic, environmentally inexpensive, and highly efficient. Thus, in our research, we work with composite materials that provide a hetero catalyst designed to crack Polyethylene high Density ( PEHD) , which is composed of Metals (Mn, Ag) in Nano scales , and Graphene impregnated inside the PEG matrix. In order to evaluate fabricated composite catalyst, to be applicable on conversion plastic polyethylene high density to gases yields and solid char carbon using pyrolysis and gasification reaction . the process were carried out inside the fixed bed reactor. Various characteristics have been conducted for final products (gases and black char), further spectroscopic analyses like Ultraviolet–visible spectroscopy (UV) , Cyclic voltammetry (CV) , Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD ), and Thermogravimetric analysis (TGA) were investigated for the new composite.

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