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- Plasma Reactor / Optimization (6)
- Catalyst for Methane Conversion (4)
- Drying Technology (3)
- Grain drying (2)
- ANN-GA (1)
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- Alternating direction implicit method (1)
- Binary metal oxide (1)
- C2 hydrocarbons (1)
- C2+ hydrocarbons (1)
- CH4 (1)
- CH4–CO2 conversions (1)
- CO2 (1)
- CO2 OCM process (1)
- CO2 OCM; CaO–MnO/CeO2 catalyst (1)
- CO2-OCM (1)
- CaO–MnO/CeO2 catalyst (1)
- Carbon (1)
- Carbon dioxide (1)
- Catalyst basicity (1)
- Catalyst reducibility (1)
- Catalyst screening (1)
- Catalysts optimization (1)
- CeO2 (1)
- Central composite design (1)
- Chemical reactors (1)
- Co-generation (1)
- Comprehensive modeling (1)
- Contribution to Book (1)
- Coupled momentum mass heat transfer (1)
- Deep bed dryers (1)
Articles 1 - 14 of 14
Full-Text Articles in Engineering
Optimization Of Methane Conversion To Liquid Fuels Over W-Cu/Zsm-5 Catalysts By Response Surface Methodology, Istadi Istadi
Optimization Of Methane Conversion To Liquid Fuels Over W-Cu/Zsm-5 Catalysts By Response Surface Methodology, Istadi Istadi
Istadi
The conversion of methane to liquid fuels is still in the development process. The modified HZSM-5 by loading with Tungsten (W) enhanced its heat resistant performance, and the high reaction temperature (800 ◦C) did not lead to the loss of W component by sublimation. The loading of ZSM-5 with Tungsten and Copper (Cu) resulted in an increment in the methane conversion, CO2, andC5+ selectivities. The high methane conversion and C5+ selectivity, and low H2O selectivity are obtained by using W/3.0Cu/ZSM-5. The optimization of methane conversion over 3.0W/3.0Cu/ZSM-5 under different temperature and oxygen concentration using response surface methodology (RSM) are studied. …
Optimization Of Methane Conversion To Liquid Fuels Over W-Cu/Zsm5 Catalysts By Response Surface Methodology, Istadi Istadi
Optimization Of Methane Conversion To Liquid Fuels Over W-Cu/Zsm5 Catalysts By Response Surface Methodology, Istadi Istadi
Istadi
The conversion of methane to liquid fuels is still in the development process. The modified HZSM-5 by loading with Tungsten (W) enhanced its heat resistant performance, and the high reaction temperature (800 °C) did not lead to the loss of W component by sublimation. The loading of ZSM-5 with Tungsten and Copper (Cu) resulted in an increment in the methane conversion, CO2, and C5+ selectivities. The high methane conversion and C5+ selectivity, and low H2O selectivity are obtained by using W/3.0Cu/ZSM-5. The optimization of methane conversion over 3.0 W/3.0Cu/ZSM-5 under different temperature and oxygen concentration using response surface methodology (RSM) …
Modelling And Optimization Of Catalytic-Dielectric Barrier Discharge Plasma Reactor For Methane And Carbon Dioxide Conversion Using Hybrid Artificial Neural Network – Genetic Algorithm Technique, Istadi, Nor Aishah Saidina Amin
Modelling And Optimization Of Catalytic-Dielectric Barrier Discharge Plasma Reactor For Methane And Carbon Dioxide Conversion Using Hybrid Artificial Neural Network – Genetic Algorithm Technique, Istadi, Nor Aishah Saidina Amin
Istadi
A hybrid Artificial Neural Network - Genetic Algorithm (ANN-GA) was developed to model, simulate and optimize the catalytic-dielectric barrier discharge plasma reactor. Effects of CH4/CO2 feed ratio, total feed flow rate, discharge voltage and reactor wall temperature on the performance of the reactor was investigated by the ANN-based model simulation. Pareto optimal solutions and the corresponding optimal operating parameter range based on multi-objectives can be suggested for two cases, i.e. simultaneous maximization of CH4 conversion and C2+ selectivity (Case 1), and H2 selectivity and H2/CO ratio (Case 2). It can be concluded that the hybrid catalytic-dielectric barrier discharge plasma reactor …
Optimization Of Process Parameters And Catalyst Compositions In Carbon Dioxide Oxidative Coupling Of Methane Over Cao–Mno/Ceo2 Catalyst Using Response Surface Methodology, Istadi Istadi, Nor Aishah Saidina Amin
Optimization Of Process Parameters And Catalyst Compositions In Carbon Dioxide Oxidative Coupling Of Methane Over Cao–Mno/Ceo2 Catalyst Using Response Surface Methodology, Istadi Istadi, Nor Aishah Saidina Amin
Istadi
The optimization of process parameters and catalyst compositions for the CO2 oxidative coupling of methane (CO2-OCM) reaction over CaO–MnO/CeO2 catalyst was developed using Response Surface Methodology (RSM). The relationship between the responses, i.e. CH4 conversion, C2 hydrocarbons selectivity or yield, with four independent variables, i.e. CO2/CH4 ratio, reactor temperature, wt.% CaO and wt.% MnO in the catalyst, were presented as empirical mathematical models. The maximum C2 hydrocarbons selectivity and yields of 82.62% and 3.93%, respectively, were achieved by the individual-response optimization at the corresponding optimal process parameters and catalyst compositions. However, the CH4 conversion was a saddle function and did …
Hybrid Artificial Neural Network-Genetic Algorithm Technique For Modeling And Optimization Of Plasma Reactor, Istadi, Nor Aishah Saidina Amin
Hybrid Artificial Neural Network-Genetic Algorithm Technique For Modeling And Optimization Of Plasma Reactor, Istadi, Nor Aishah Saidina Amin
Istadi
A hybrid artificial neural network-genetic algorithm (ANN-GA) numerical technique was successfully developed to model, to simulate, and to optimize a dielectric barrier discharge (DBD) plasma reactor without catalyst and heating. Effects of CH4/CO2 feed ratio, total feed flow rate, and discharge voltage on the performance of noncatalytic DBD plasma reactor were studied by an ANN-based simulation with a good fitting. From the multiobjectives optimization, the Pareto optimal solutions and corresponding optimal process parameter ranges resulted for the noncatalytic DBD plasma reactor owing to the optimization of three cases, i.e., CH4 conversion and C2+ selectivity, CH4 conversion and C2+ yield, and …
Synergistic Effect Of Catalyst Basicity And Reducibility On Performance Of Ternary Ceo2-Based Catalyst For Co2 Ocm To C2 Hydrocarbons, Istadi, Nor Aishah Saidina Amin
Synergistic Effect Of Catalyst Basicity And Reducibility On Performance Of Ternary Ceo2-Based Catalyst For Co2 Ocm To C2 Hydrocarbons, Istadi, Nor Aishah Saidina Amin
Istadi
The present investigation focuses on the synergistic effect of catalyst basicity and reducibility on the catalytic activity of binary and ternary CeO2-based catalysts in the CO2 oxidative coupling of methane (CO2 OCM). Proper amount of medium and strong basic sites together with lower amount of very strong basic sites are identified as pertinent factors in increasing the catalytic performance. The CO2-TPD and H2-TPR studies indicate synergistic effect between the catalyst basicity and reducibility for the 12.8CaO–6.4MnO/CeO2 ternary metal-oxide catalyst in enhancing the CO2 OCM performance.
Selective Conversion Of Methane To C2 Hydrocarbons Using Carbon Dioxide As An Oxidant Over Cao-Mno/Ceo2 Catalyst, Nor Aishah Saidina Amin, Istadi Istadi
Selective Conversion Of Methane To C2 Hydrocarbons Using Carbon Dioxide As An Oxidant Over Cao-Mno/Ceo2 Catalyst, Nor Aishah Saidina Amin, Istadi Istadi
Istadi
Carbon dioxide rather than oxygen seemed to be an alternative oxidant for the catalytic reaction of methane to produce C2 hydrocarbons via oxidative coupling of methane (CO2 OCM). The proper amount of medium and strong basic sites and the reducibility of the catalyst enhanced the C2 hydrocarbon selectivity and yield, which may be due to the synergistic effect of CeO2, CaO and MnO in the catalyst. The C2 hydrocarbons selectivity and yield of 75.6% and 3.9%, respectively were achieved over the 12.8CaO-6.4MnO/CeO2 catalyst. The catalyst showed a remarkable stability for 20 h time on stream in the CO2 OCM process
Co-Generation Of Synthesis Gas And C2c Hydrocarbons From Methane And Carbon Dioxide In A Hybrid Catalytic-Plasma Reactor: A Review, Istadi, Nor Aishah Saidina Amin
Co-Generation Of Synthesis Gas And C2c Hydrocarbons From Methane And Carbon Dioxide In A Hybrid Catalytic-Plasma Reactor: A Review, Istadi, Nor Aishah Saidina Amin
Istadi
The topics on conversion and utilization of methane and carbon dioxide are important issues in tackling the global warming effects from the two greenhouse gases. Several technologies including catalytic and plasma have been proposed to improve the process involving conversion and utilization of methane and carbon dioxide. In this paper, an overview of the basic principles, and the effects of CH4/CO2 feed ratio, total feed flow rate, discharge power, catalyst, applied voltage, wall temperature, and system pressure in dielectric-barrier discharge (DBD) plasma reactor are addressed. The discharge power, discharge gap, applied voltage and CH4/CO2 ratio in the feed showed the …
Co-Generation Of C2 Hydrocarbons And Synthesis Gases From Methane And Carbon Dioxide: A Thermodynamic Analysis, Istadi Istadi, Nor Aishah Saidina Amin
Co-Generation Of C2 Hydrocarbons And Synthesis Gases From Methane And Carbon Dioxide: A Thermodynamic Analysis, Istadi Istadi, Nor Aishah Saidina Amin
Istadi
This paper deals with thermodynamic chemical equilibrium analysis using the method of direct minimization of Gibbs free energy for all possible CH4 and CO2 reactions. The effects of CO2/CH4 feed ratio, reaction temperature, and system pressure on equilibrium composition, conversion, selectivity and yield were studied. In addition, carbon and no carbon formation regions were also considered at various reaction temperatures and CO2/CH4 feed ratios in the reaction system at equilibrium. It was found that the reaction temperature above 1100 K and CO2/CH4 ratio=1 were favourable for synthesis gas production with H2/CO ratio unity, while carbon dioxide oxidative coupling of methane …
A Hybrid Numerical Approach For Multi-Responses Optimization Of Process Parameters And Catalyst Compositions In Co2 Ocm Process Over Cao-Mno/Ceo2 Catalyst, Istadi Istadi
Istadi
A new hybrid numerical approach, using Weighted Sum of Squared Objective Functions (WSSOF) algorithm, was developed for multiresponses optimization of carbon dioxide oxidative coupling of methane (CO2 OCM). The optimization was aimed to obtain optimal process parameters and catalyst compositions with high catalytic performances. The hybrid numerical approach combined the single-response modeling and optimization using Response Surface Methodology (RSM) and WSSOF technique of multi-responses optimization. The hybrid algorithm resulted in Pareto-optimal solutions and an additional criterion was proposed over the solutions to obtain a final unique optimal solution. The simultaneous maximum responses of C2 selectivity and yield were obtained at …
Screening Of Mgo- And Ceo2-Based Catalysts For Carbon Dioxide Oxidative Coupling Of Methane To C2+ Hydrocarbon, Istadi, Nor Aishah Saidina Amin
Screening Of Mgo- And Ceo2-Based Catalysts For Carbon Dioxide Oxidative Coupling Of Methane To C2+ Hydrocarbon, Istadi, Nor Aishah Saidina Amin
Istadi
The catalyst screening tests for carbon dioxide oxidative coupling of methane (CO2-OCM) have been investigated over ternary and binary metal oxide catalysts. The catalysts are prepared by doping MgO- and CeO2-based solids with oxides from alkali (Li2O), alkaline earth (CaO), and transition metal groups (WO3 or MnO). The presence of the peroxide (O2_2 ) active sites on the Li2O2, revealed by Raman spectroscopy, may be the key factor in the enhanced performance of some of the Li2O/MgO catalysts. The high reducibility of the CeO2 catalyst, an important factor in the CO2-OCM catalyst activity, may be enhanced by the presence of …
Modelling And Simulation Of Momentum, Heat, And Mass Transfer In A Deep-Bed Grain Dryer, Istadi Istadi, Johnner P. Sitompul, Siswo Sumardiono
Modelling And Simulation Of Momentum, Heat, And Mass Transfer In A Deep-Bed Grain Dryer, Istadi Istadi, Johnner P. Sitompul, Siswo Sumardiono
Istadi
This article concerns the modelling and simulation of a deep-bed grain dryer in a large diameter-column. Two-dimensional (2D) models of deep-bed grain dryers were built by considering simultaneously momentum, heat, and mass transfer in the drying phase together with coupled heat and mass balance in the grain phase. The dynamic equations are solved numerically by using finite difference method. The momentum equations are applied to simulate pressure drop and velocity field of the drying air across the bed. The mass and heat balance in the two phases determine the profile of temperature and moisture content in both phases. Further, drying …
A Comprehensive Mathematical And Numerical Modeling Of Deep-Bed Grain Drying, Istadi Istadi, Johnner P. Sitompul
A Comprehensive Mathematical And Numerical Modeling Of Deep-Bed Grain Drying, Istadi Istadi, Johnner P. Sitompul
Istadi
This paper deals with comprehensive mathematical and numerical modeling of deep-bed grain drying. In order to build the process model, it is necessary to analyze the transport in both grain and gas phases. Experimental works were carried out for a layer of grain bed in order to validate the models. The models consider momentum, energy, and mass conservation within grain and drying air phase. The twodimensional dynamic equations of energy and mass conservation are solved numerically by finite-difference method (FDM) and utilizing alternating direction implicit algorithm within grain and drying air phase, while momentum conservation are solved by finite difference …
Modelling And Simulation Of Deep-Bed Grain Dryers, Johnner P. Sitompul, Istadi Istadi, I Nyoman Widiasa
Modelling And Simulation Of Deep-Bed Grain Dryers, Johnner P. Sitompul, Istadi Istadi, I Nyoman Widiasa
Istadi
This paper concerns with heterogeneous modeling of deepbed grain dryers based on two-phase model by taking into account coupled heat and mass transfer within grains. This model also consider axial mass and heat dispersion in the fluid phase. The dynamictwo-phase equations are solved numerically by finite difference with alternating direction implicit method algorithm, and then applied to simulate humidity and temperature profile of drying gas across dryers together with moisture content and temperature of grains. The capabilities of these models were compared with experimental data obtained from available literatures, under drying conditions such as temperature and absolute humidity of drying …