Kinetic Study of the Simultaneous Cracking of Paraffins and Methanol on HZSM-5 Zeolite Catalysts

2007 ◽  
Vol 5 (1) ◽  
Author(s):  
Diana Mier ◽  
Andrés Tomás Aguayo ◽  
Alaitz Atutxa ◽  
Ana G Gayubo ◽  
Javier Bilbao
Keyword(s):  
Kinetic Model ◽  
Catalyst Deactivation ◽  
Fixed Bed ◽  
Acid Catalyst ◽  
Product Distribution ◽  
Operating Conditions ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Light Olefins ◽  
Feed Temperature

A study has been carried out on the effect of acid catalyst properties and operating conditions (methanol/n-butane ratio in the feed, temperature, space time, time on stream) on the yield of light olefins (C2-C4) in the simultaneous cracking of n-butane and methanol. The operation has been carried out in an isothermal fixed bed reactor in the 400-575 °C range, using catalysts prepared based on HZSM-5 zeolites (with different Si/Al ratio), HY, Ni/HZSM-5 and SAPO-18. The results are evidence of a synergism between the transformation reactions of both reactants, whose consequence is an increase in the yield of olefins that correspond to the transformation of methanol and the cracking of n-butane. Furthermore, catalyst deactivation by coke is significantly attenuated compared to the corresponding transformation of methanol. Based on the effect of operating conditions on product distribution, a kinetic model is proposed by combining the schemes corresponding to the transformation of individual components.

Development of a Kinetic Model for Modeling the Industrial VGO Hydrocracker Accompanied By Deactivation

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Azita Barkhordari ◽  
Shohreh Fatemi ◽  
Mahdi Daneshpayeh ◽  
Hossain Zamani
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Catalyst Deactivation ◽  
Fixed Bed ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Fixed Bed Reactor ◽  
Wide Range ◽  
Silica Alumina ◽  
Parallel Reactions

Two types of kinetic modeling, continuous and discrete lump model were studied and compared in this research in order to model the industrial scale VGO hydrocracking process. The experimental data obtained from a pilot-scale fixed bed reactor over Ni-Mo/Silica-Alumina catalyst in a wide range of operating conditions was used for prediction and tuning the kinetic parameters using Genetic algorithm. In this study, the discrete lump model with four parallel reactions to four lumped products showed more convergence to the experimental data than the continuous lump model. Afterward, the discrete kinetic model was used to simulate the vacuum gas oil (VGO) industrial hydrocracking reaction accompanied by catalyst deactivation. The activity of the catalyst was taken as a time dependent variable and the first year of operational data were used to derive the deactivation parameter. The refinery test runs spanning over the last two and half years of operation were used to validate the model and interpret the simulation results. A comparison between the industrial and the predicted data showed that there is a good agreement between them and the presented model provides a reasonable fit to estimate the product yields of LPG, naphtha, kerosene, diesel.

Effect of Silica Base Catalyst on Transformation of Methanol to Hydrocarbon

2017 ◽  
Vol 751 ◽  
pp. 512-517 ◽  
Author(s):  
Supranee Lao-Ubol ◽  
Phunthinee Somwongsa ◽  
Pracha Laoauyporn ◽  
Pasinee Panith ◽  
Siriporn Larpkiattaworn ◽  
...  
Keyword(s):  
Pore Diameter ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Liquid Hydrocarbon ◽  
Product Distribution ◽  
Catalytic Performance ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Phosphorus Species ◽  
Methanol To Hydrocarbon

Five different types of silica catalyst (SBA-15, SBA-15-PO3H2, and three different Si/Al ratio of commercial zeolites (30, 80 and 280) were used to study the transformation of methanol to hydrocarbon (MTH). The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity. The mesoporous silica catalysts were prepared by co-condensation method. The catalysts samples were characterized by GC-MS, XRD, BET, and NH3-TPD techniques. The catalytic performance of synthesized and commercial catalysts for MTH process was evaluated using a homemade fixed bed reactor at temperature (300°C). It was found that the liquid hydrocarbon product provided by zeolite catalysts is aromatic hydrocarbons-rich. High Si/Al zeolites with larger pore size lead to higher selectivity and yield to paraffins (C1-C7). In contrast to commercial zeolite catalyst, SBA-15 and its modification with phosphorus species showed no conversion under studied condition. These results indicate that both pore diameter and acidity influence the product distribution in methanol to hydrocarbon process.

Hydrogenation of Acetylene: Kinetic Studies and Reactor Modeling

2005 ◽  
Vol 3 (1) ◽  
Author(s):  
Navid Mostoufi ◽  
Ali Ghoorchian ◽  
Rahmat Sotudeh-Gharebagh
Keyword(s):  
Experimental Data ◽  
Catalyst Deactivation ◽  
Fixed Bed ◽  
Kinetic Studies ◽  
Operating Conditions ◽  
Fixed Bed Reactor ◽  
Reactor Modeling ◽  
Deactivation Rate Constant ◽  
Hydrogenation Reactor ◽  
Kinetics Of

The kinetics of acetylene hydrogenation has been studied in a fixed bed reactor of a commercial Pd/Al2O3 catalyst. The experiments were carried out at 30, 50 and 70 ºC with various feed compositions at atmospheric pressure. The experiments were repeated at 70 ºC in the presence of the used catalyst to determine the effect of the catalyst deactivation where the corresponding deactivation rate constant was determined in order to predict the activity of the catalyst during each run. Two well known kinetic models were used for a nearly similar catalyst to predict the experimental data of this work and none of them were found satisfactory. A new model was then proposed to fit the experimental data. The hydrogenation reactor was also simulated at industrial operating conditions with the proposed kinetics for both plug and dispersion flows. The results of these simulations were almost close to each other in most cases.

scholarly journals A Comprehensive Kinetic Model of Fischer-Tropsch Synthesis over Supported Cobalt Catalyst

2017 ◽  
Author(s):  
Reza Jalilzadeh ◽  
Mahmoud Moqadam
Keyword(s):  
Kinetic Model ◽  
Fixed Bed ◽  
Operating Conditions ◽  
Tropsch Synthesis ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Rate Equations ◽  
Type Model ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis

A comprehensive kinetic model of the Fischer-Tropsch synthesis (FTS) is developed in a fixed bed reactor under operating conditions (temperature, 230–235°C, pressure, 20–25 bar, gas hourly space velocity, 4000–5000 cm3(STP)/h/gcatalyst ,H2/CO feed molar ratio, 2.1) over a Co based catalyst. Reaction rate equations based on Eley-Rideal (ER) type model for initiation step and Langmuir-Hinshelwood-Hougen-Watson (LHHW) type model for propagation and termination steps of the FTS reactions have been considered and the readsorption of olefins were taken into account. The model that was reported in the literature was modified in order to explain many significant deviations from the ASF distribution. Optimum parameters have been obtained by Genetic Algorithms (GA). The calculated activation energies to produce n-paraffins and 1-olefins were in the range of 82.24 to 90.68 kJ/mol and 100.66 to 105.24 kJ/mol, respectively. The hydrocarbon distribution in FTS reactions was satisfactorily predicted particularly for paraffins.

Development and experimental validation of reactor kinetic model for catalytic cracking of eugenol, a potential bio additive fuel blend

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mythily Mani ◽  
Thyagarajan Thangavelu ◽  
Santhana Krishnan Perumal ◽  
Shanthi Kannan
Keyword(s):  
Kinetic Model ◽  
Real Time ◽  
Catalytic Cracking ◽  
Catalyst Deactivation ◽  
Fixed Bed ◽  
Integrated Model ◽  
Fixed Bed Reactor ◽  
Design Parameters ◽  
Exhaust Emission ◽  
Time Data

Abstract An integrated kinetic model representing catalytic cracking of eugenol in a fixed bed reactor is developed. Eugenol, a major component of clove oil can act as the most potential bio additive fuel for improving the diesel quality thereby reducing the exhaust emission of the engine. The proposed integrated model includes four lump kinetic model which is plugged with catalyst deactivation model. The reactor design parameters are also included in the integrated model. The effectiveness of the proposed integrated model is compared with the conventional kinetic models and the results are presented. The proposed integrated model is validated against the real time data obtained by conducting an experiment in a real time setup with MoS2(Ni2P) Al-SBA-15(10) as the catalyst. The advantages of the proposed integrated model are highlighted.

Activity of Copper and Nickel Loaded on HZSM-5Zeolite Based Catalyst for Steam Reforming of Glycerol to Hydrogen

2014 ◽  
Vol 699 ◽  
pp. 504-509
Author(s):  
Hafizah Abdul Halim Yun ◽  
Ramli Mat ◽  
Tuan Amran Tuan Abdullah ◽  
Mahadhir Mohamed ◽  
Anwar Johariand Asmadi Ali
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Operating Conditions ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Molar Ratio ◽  
Hydrogen Yield ◽  
Impregnation Method ◽  
Glycerol Conversion

The study focuses on hydrogen production via glycerol steam reforming over copper and nickel loaded on HZSM-5 zeolite based catalyst. The catalysts were prepared by using different loading amount of copper (0-10wt%) and nickel (0-10wt%) on HZSM-5 zeolite catalysts through wet impregnation method and was characterized by X-Ray Diffraction (XRD). The performances of catalysts were evaluated in terms of glycerol conversion and hydrogen production at 500°C using 6:1 of water to glycerol molar ratio (WGMR) in a tubular fixed bed reactor. All the catalysts had achieved more than 85% of glycerol conversion except that of 5%Cu loaded on HZSM-5 catalyst. The addition of nickel into 5% Cu/HZSM-5 catalyst had increased the hydrogen yield. Similar trend was observed when copper was added into Ni/HZSM-5 catalyst but using copper loaded on HZSM-5 alone was unable to produce hydrogen compared to using nickel catalyst alone. It showed that copper acted as a promoter for hydrogen production. It was established that a 5wt% of Cu with 10wt% of Ni loaded on HZSM-5 catalyst showed significant improvement in terms of hydrogen yield and gaseous product compositions at selected operating conditions.

Intrinsic Kinetics Study of CO Methanation on Ni-Mo-SiO2 Catalyst Prepared by Hydrothermal Method

2018 ◽  
Vol 921 ◽  
pp. 40-47
Author(s):  
Jia Ying Zhang
Keyword(s):  
Kinetic Model ◽  
Orthogonal Design ◽  
Fixed Bed ◽  
Reaction Network ◽  
Space Velocity ◽  
Operating Conditions ◽  
Least Square ◽  
Fixed Bed Reactor ◽  
Consecutive Reaction ◽  
Wide Range

A comprehensive kinetic model for methanation of syngas on Ni-Mo-SiO2catalyst was developed on a fixed bed reactor data. The CO and H2conversion, methane selectivity and yield were obtained in a wide range of operating conditions including 300 < T < 450°C, 1 < H2/CO <4 and 0.1 < P < 1.5 MPa with the total weight hourly space velocity (WHSV) of 60000 ml/h/g. A 6-step reaction scheme defined to the description of a reaction network that considers both catalytic and gas-phase as well as primary and consecutive reaction steps to predict the performance of the syngas methantion. Orthogonal design method was adopted to select test points with temperature, pressure and feed compositions as factors and the kinetic rates involved Langmuir – Hinshelwood equation kinetic model. The kinetic rate parameters were estimated using the Least Square Method by MATLAB. Comparing the experimental and model predicted data showed that presented model has a reasonable fit between the experimental data and the predicted values with average absolute relative deviation of ±9.8%.

scholarly journals Kinetics of Hydrogenation of Acetic Acid to Ethanol

2019 ◽  
Vol 31 (12) ◽  
pp. 2915-2923
Author(s):  
Qiang Chen ◽  
Xuebing Zhang ◽  
Shuxun Tian ◽  
Junying Long ◽  
Xiangkun Meng ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Kinetic Model ◽  
Reaction Temperature ◽  
Active Sites ◽  
Fixed Bed ◽  
Space Velocity ◽  
Operating Conditions ◽  
Fixed Bed Reactor ◽  
Model Parameters ◽  
Intrinsic Kinetic

The intrinsic kinetic behaviour of catalytic hydrogenation of acetic acid in vapour phase was studied over a multi-metallic catalyst. The rate expression was derived from the sequence of elementary reaction steps based on a Langmuir-Hinshelwood-model involving two types of active sites. Experiments were carried out in a fixed bed reactor, which is similar to an isothermal integral reactor designed to excluding the negative effects of internal and external diffusion. The reaction conditions investigated were as follow:reaction temperature 275-325 ºC, reaction pressure1.5-3.0 MPa, liquid hourly space velocity (sv) 0.3-1.2 h-1, molar ratio of hydrogen to acetic acid (H/AC) 8:20. The results show that conversion of acetic acid increases with increasing the reaction temperature and pressure, but decreases with increasing the space velocity and H/AC. Furthermore, reducing the reaction pressure and increasing reaction temperature, space velocity and H/AC can improve the reaction selectivity of acetic acid to ethanol. The established kinetic model results agreed with experimental results. The relative difference between the calculated value and the experimental value is less than 6 %. The values of model parameters are consistent with the three thermodynamic constraints. The study provided evidence that the intrinsic kinetic model is suitable both mathematically and thermodynamically, and it could be useful in guiding reactor design and optimization of operating conditions.

LPG Synthesis from Syngas over Cu/ZnO-Pd-β Catalysts Prepared by Ultrasonic Spray Pyrolysis

2015 ◽  
Vol 659 ◽  
pp. 252-256
Author(s):  
Sudarat Chaiwatyothin ◽  
Wittawat Ratanathavorn ◽  
Tharapong Vitidsant ◽  
Prasert Reubroycharoen
Keyword(s):  
Spray Pyrolysis ◽  
Fixed Bed ◽  
Ultrasonic Spray Pyrolysis ◽  
Product Distribution ◽  
Fixed Bed Reactor ◽  
Spherical Particles ◽  
Gaseous State ◽  
X Ray ◽  
Ultrasonic Spray ◽  
Co Conversion

Synthesis of nanoCu/ZnO catalyst for LPG production was prepared by ultrasonic spray pyrolysis (USP). Hollow spherical particles were obtained by USP technique using an aqueous solution of Cu (NO3)3.6H2O and Zn (NO3)3.3H2O with different concentration of 0.05, 0.1 and 0.5 molar under the pyrolysis temperatures of 600, 700 and 800°C. Mists of the solution were generated from the precursor solution by ultra sonic vibrators at frequency of ~1.7 MHz. The physicochemical properties of catalysts were characterized by X-ray diffraction, temperature-programmed reduction, scanning electron microscope, nitrogen adsorption-desorption, and energy dispersive X-ray spectrometer. The results showed that increasing in precursor concentration resulted in a large particle and particles size distributed in a range of 0.63-1.21 μm. Particles prepared at pyrolysis temperature 700°C exhibited homogeneous in size and shape compared to other temperature. The catalytic activity of nanoCu/ZnO-Pd-β catalysts was performed in a fixed-bed reactor for synthesizing LPG. The reaction took place at 260°C, 3.0 MPa, and the ratio of H2/CO = 2/1. All the products from the reactor were in gaseous state, and analyzed by on-line gas chromatography. The results showed that %CO conversion was high but decreased rapidly with increasing reaction time. Cu/ZnO catalyst prepared by co-precipitation gave higher %CO conversion than that prepared by ultrasonic spray pyrolysis. Moreover, hydrocarbon product distribution for Cu/ZnO catalyst produced at concentration 0.1 M 700°C by ultrasonic spray pyrolysis gave the highest LPG selectivity.

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