Modeling and Optimization of MeOH to DME in Isothermal Fixed-bed Reactor

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohammad Farsi ◽  
Abdolhossein Jahanmiri ◽  
Reza Eslamloueyan
Keyword(s):  
Fixed Bed ◽  
Methanol Conversion ◽  
Fixed Bed Reactor ◽  
Methanol Dehydration ◽  
Algebraic Equations ◽  
Optimal Temperature ◽  
Heterogeneous Model ◽  
One Dimensional ◽  
Shell And Tube ◽  
Green Fuel

Dimethyl ether (DME) is a green fuel that commercially produced in an adiabatic fixed bed reactor by methanol dehydration. In the present work, a shell and tube fixed bed reactor is modeled and optimized for DME production. The reactor is modeled based on mass and energy conservation equations as well as auxiliary equations. In order to estimate the DME production and temperature profile along the reactor, a one dimensional heterogeneous model consist of a set of nonlinear differential and algebraic equations has been solved numerically. Also, The DME production in the isothermal reactor is maximized by adjusting the optimal temperature distribution along the reactor using genetic algorithm. Then, the performance of the proposed isothermal reactor is compared with industrial adiabatic fixed bed reactor. Results showed the higher DME production rate and methanol conversion in the optimized reactor.

Dimethyl Ether Synthesis via Methanol Dehydration over Diatomite Catalyst Modified Using Hydrochloric Acid

2014 ◽  
Vol 931-932 ◽  
pp. 42-46 ◽  
Author(s):  
Watcharakorn Pranee ◽  
Pornsawan Assawasaengrat ◽  
Arthit Neramittagapong ◽  
Sutasinee Neramittagapong
Keyword(s):  
Hydrochloric Acid ◽  
Dimethyl Ether ◽  
Active Sites ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Methanol Dehydration ◽  
Dimethyl Ether Synthesis ◽  
Ether Synthesis

The synthesis of dimethyl ether via methanol dehydration has been carried out over untreated-diatomite catalyst (DM) and hydrochloric acid modified treatment on diatomite catalyst (DMHC). The reactions were carried out in a fixed-bed reactor. The effects of hydrochloric acid modifications of diatomite on its catalytic performance were studied. The characterization such as XRD, SEM, FT-IR and FT-Raman had no deformation after HCl-modified treatment on catalysts. DMHC catalyst apparently gave the higher methanol conversion rate than DM due to the acidity while the selectivity of dimethyl ether from 250 to 350°C was slightly changed. The acidity was depended upon Al(IV) ions; nevertheless, both Al(V) and Al(VI) were affected and hence increasing the basic active sites. Not only was the competitively catalytic methanol dehydrogenation preferred with basic condition but also methanol-blocking water molecule interaction was the unwanted reaction. In this investigation, the chemical-bond arrangements of silicon and aluminium ions were proposed with solid MAS/NMR. The DMHC catalyst exhibited better DME yield than the DM catalyst, and it could be used as a selective catalyst for DME synthesis from methanol.

Hydrogen Production from Ethanol Steam Reforming: Fixed Bed Reactor Design

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Pablo Giunta ◽  
Norma Amadeo ◽  
Miguel Laborde
Keyword(s):  
Steam Reforming ◽  
Flow Model ◽  
Multicomponent Mixture ◽  
Plug Flow ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Ethanol Steam Reforming ◽  
Heterogeneous Model ◽  
Ethanol Steam ◽  
Hydrogen Stream

The aim of this work is to design an ethanol steam reformer to produce a hydrogen stream capable of feeding a 60 kW PEM fuel cell applying the plug flow model, considering the presence of the catalyst bed (heterogeneous model). The Dusty-Gas Model is employed for the catalyst, since it better predicts the fluxes of a multicomponent mixture. Moreover, this model has shown to be computationally more robust than the Fickian Model. A power law-type kinetics was used. Results showed that it is possible to carry out the ethanol steam reforming in a compact device (1.66 x 10 -5 to 5.27 x 10 -5 m3). It was also observed that this process is determined by heat transfer.

scholarly journals Hierarchical H-ZSM5 zeolites based on natural kaolinite as a high-performance catalyst for methanol to aromatic hydrocarbons conversion

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ahmad Asghari ◽  
Mohammadreza Khanmohammadi Khorrami ◽  
Sayed Habib Kazemi
Keyword(s):  
Pore Size ◽  
Aromatic Hydrocarbons ◽  
High Performance ◽  
Low Cost ◽  
Direct Synthesis ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Good Prospect

AbstractThe present work introduces a good prospect for the development of hierarchical catalysts with excellent catalytic performance in the methanol to aromatic hydrocarbons conversion (MTA) process. Hierarchical H-ZSM5 zeolites, with a tailored pore size and different Si/Al ratios, were synthesized directly using natural kaolin clay as a low-cost silica and aluminium resource. Further explored for the direct synthesis of hierarchical HZSM-5 structures was the steam assisted conversion (SAC) with a cost-effective and green affordable saccharide source of high fructose corn syrup (HFCS), as a secondary mesopore agent. The fabricated zeolites exhibiting good crystallinity, 2D and 3D nanostructures, high specific surface area, tailored pore size, and tunable acidity. Finally, the catalyst performance in the conversion of methanol to aromatic hydrocarbons was tested in a fixed bed reactor. The synthesized H-ZSM5 catalysts exhibited superior methanol conversion (over 100 h up to 90%) and selectivity (over 85%) in the methanol conversion to aromatic hydrocarbon products.

Simulation Studies of Steam Reforming of Methane using Ni-Al2O3 Catalysts

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Giane Gonçalves Lenzi ◽  
Ervin Kaminski Lenzi ◽  
Cláudio Vilas Boas Fávero ◽  
Marcelo Kaminski Lenzi ◽  
Regina Maria Matos Jorge ◽  
...  
Keyword(s):  
Sol Gel ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Co2 Production ◽  
Simulation Studies ◽  
One Dimensional ◽  
Wgs Reaction ◽  
Different Characteristics ◽  
Water Gas ◽  
Al2o3 Catalyst

This paper reports the results of reforming methane into synthesis gas using industrial Ni-Al2O3 catalyst (75% NiO wt.) and Ni-Al2O3 produced by the sol gel method (8% Ni wt.). A mathematical investigation on the performance of a one-dimensional model of catalytic conventional fixed-bed reactor was developed and implemented for the process. The results indicated that the industrial catalyst favored the water gas shift (WGS) reaction increasing CO2 production. However in temperatures of 773 and 973 K the yield (H2/CH4,reacted) was more efficient for the sol-gel catalyst. This result is possibly due to the different characteristics as specific surface area and temperature reduction. The model validation for the adjustment parameters U and a1 was more efficient for temperature profiles (2% error) than for mole fraction (10% error).

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.

CFD modeling of methanol to light olefins process in a sodalite membrane reactor on SAPO-34 catalyst with in situ steam removal

2020 ◽  
Vol 23 ◽  
Author(s):  
Abbas Aghaeinejad-Meybodi ◽  
Seyed Mahdi Mousavi ◽  
Ali Asghar Shahabi ◽  
Mohammad Rostampour Kakroudi
Keyword(s):  
Membrane Reactor ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Fixed Bed Reactor ◽  
Light Olefins ◽  
Cfd Modeling ◽  
Cfd Model ◽  
Ethylene Propylene ◽  
Mto Process

Aims and Objective: In this work, the performance of sodalite membrane reactor (MR) in methanol to olefins (MTO) process was evaluated for ethylene and propylene production with in situ steam removal using 3-dimensional CFD (computational fluid dynamic) technique. Methods: The local information of component concentration for methanol, ethylene, propylene, and water was obtained by the proposed CFD model. Literature data were applied to validate model results, and between experimental data and predicted results using CFD model, a good agreement was attained. In the sodalite MR model, a commercial SAPO-34 catalyst in the reaction zone was selected. The influence of key operation parameters including pressure and temperature on methanol con-version, water recovery, and yields of ethylene, propylene, and water was studied to evaluate the performance of sodalite MR. Permeation flux through the sodalite membrane was increased by an increase of reaction temperature which led to enhance-ment of water stream recovered in the permeate side. Result and Conclusion: The CFD modeling results showed that the sodalite MR in MTO process has higher performance regarding methanol conversion compared to the fixed-bed reactor (methanol conversion of 97% and 89% at 733 K for sodalite MR and fixed-bed reactor, respectively).

The Optimization of an Ammonia Synthesis Reactor Using Genetic Algorithm

2009 ◽  
Vol 6 (1) ◽  
Author(s):  
Mohammad Taghi Sadeghi ◽  
Azam Kavianiboroujeni
Keyword(s):  
Genetic Algorithm ◽  
Ammonia Synthesis ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Ammonia Production ◽  
Dimensional Model ◽  
Reactor Performance ◽  
One Dimensional ◽  
Operational Conditions ◽  
Quench Temperature

An industrial ammonia synthesis reactor was studied in order to optimize its operational conditions by means of increasing overall ammonia production. A heterogeneous, one-dimensional model and a two-dimensional rigorous model were utilized to evaluate the process behavior. The simulation results of the two models were compared with data from an industrial ammonia plant. The one-dimensional model was found to be adequate for optimization purposes. Applying the Genetic Algorithm (GA) as a powerful method for complex problems, the model was employed to optimize the reactor performance in varying its quench flows. The optimal temperature profile along the fixed bed reactor was studied by changing independent variables including the quench temperature and the quench flow rates. Optimization results show that the optimum quench temperature is about 615°K and that the optimum quench flows can enhance ammonia production rate by 3.3%.

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