The Experts below are selected from a list of 4743 Experts worldwide ranked by ideXlab platform
Francisco Ortega - One of the best experts on this subject based on the ideXlab platform.
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light cracked Naphtha processing controlling chemistry for maximum propylene production
Catalysis Today, 2005Co-Authors: Avelino Corma, Francisco V Melo, Laurent Sauvanaud, Francisco OrtegaAbstract:As propylene market is expanding, new production paths have to be found. The cracking of light olefins contained in several Naphthas seems to be a good alternative for responding to this demand. Results of light FCC Naphtha cracking have shown that selectivity towards propylene is governed by hydrogen-transfer reactions. Thus, the selectivity to propylene may be increased by minimizing these reactions. This can be achieved by cracking the Naphtha at high temperature, by using shape-selective catalysts or by working with coked catalysts. Recycling light Naphtha in the FCC process is an interesting alternative, which may increase the yield of propylene by 50% if proper processing is carried out. Furthermore, olefins content of FCC gasoline may be significantly reduced.
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different process schemes for converting light straight run and fluid catalytic cracking Naphthas in a fcc unit for maximum propylene production
Applied Catalysis A-general, 2004Co-Authors: Avelino Corma, Francisco V Melo, Laurent Sauvanaud, Francisco OrtegaAbstract:Light straight run (LSR) and fluid catalytic cracking (FCCN) Naphthas were cracked in a transported bed reactor (MicroDowner) and in a fixed bed reactor (MAT) over a commercial Y zeolite based catalyst, over a commercial ZSM-5 zeolite based additive, and over a mixture of both at selected conditions. Based on the mechanisms through which Naphtha hydrocarbons are converted, we evaluated the best alternatives for processing these streams to produce light olefins and/or to reduce olefins content in commercial gasoline. The experimental set-up allowed us to simulate the cracking behaviour of the different Naphtha streams in a fluid catalytic cracking (FCC) unit by different processing schemes. Results indicate that LSR only cracks at high severity, yielding large amounts of dry gas. Despite its high olefins content, FCCN practically does not crack when it is fed together with gas oil feed. When cracking FCCN alone at typical gas oil cracking conditions, olefins are transformed preferentially into Naphtha-range isoparaffins and aromatics, and when cracking FCCN at high severity, olefins are transformed preferentially into propylene and butylenes. Finally, cracking Naphtha in the stripper produces some propylene and increases the aromatics in the remaining gasoline.
M R Rahimpour - One of the best experts on this subject based on the ideXlab platform.
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modeling of Naphtha reforming unit applying detailed description of kinetic in continuous catalytic regeneration process
Chemical Engineering Research & Design, 2014Co-Authors: Davood Iranshahi, Mohsen Karimi, Shahram Amiri, Mitra Jafari, Razieh Rafiei, M R RahimpourAbstract:Abstract Naphtha reforming is one of the most important processes in refineries in which high value-added reformate for gasoline pool and aromatics such as benzene, toluene, and xylene are produced. It is necessary to establish new Naphtha reforming units and develop the traditional units to increase the efficiency of the processes. In this study, according to the recent progresses in the Naphtha reforming technology, mathematical modeling of this process in continuous catalyst regeneration mode of operation is accomplished in two dimensions (radial and axial) by considering cross flow pattern. In addition, a new catalyst deactivation model has been proposed and a new reaction network model based on 32 pseudo-components with 84 reactions is investigated. Then, this model has been validated by comparing with industrial data, and its results have acceptable agreement.
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progress in catalytic Naphtha reforming process a review
Applied Energy, 2013Co-Authors: M R Rahimpour, Mitra Jafari, Davood IranshahiAbstract:Catalytic Naphtha reforming process is a vital process for refineries due to the production of high-octane components, which is intensely demanded in our modern life. The significance of this industrial process induced researchers to investigate different aspects of catalytic Naphtha reforming process intensively. Some of the investigators try to improve this process by representing more effective catalysts, while others try to elucidate its kinetic and deactivation mechanisms and design more efficient reactor setups. The amount of these established papers is so much that may confuse some of the researchers who want to find collective information about catalytic Naphtha reforming process. In the present paper, the published studies from 1949 until now are categorized into three main groups including finding suitable catalyst, revealing appropriate kinetic and deactivation model, and suggesting efficient reactor configuration and mode of operation. These studies are reviewed separately, and a suitable reference is provided for those who want to have access to generalized information about catalytic Naphtha reforming process. Finally, various suggestions for revamping the catalytic Naphtha reforming process have been proposed as a guideline for further investigations.
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combining continuous catalytic regenerative Naphtha reformer with thermally coupled concept for improving the process yield
International Journal of Hydrogen Energy, 2013Co-Authors: Mitra Jafari, Davood Iranshahi, Mohsen Karimi, Shahram Amiri, Razieh Rafiei, M R Rahimpour, Hojjat MahdiyarAbstract:Abstract Advancements in the catalytic Naphtha reforming process, as one of the main processes in petrochemical industry, contributed to development of continuous catalytic regenerative Naphtha reformer units. Increasing the yield of aromatic and hydrogen as well as saving the energy in this process through the application of thermal coupling technique is a potentially interesting idea. This novel idea has been assessed in this paper. In the proposed configuration, continuous catalyst regeneration Naphtha reforming process is coupled with hydrogenation of nitrobenzene in a two co-axial reactor separated by a solid wall, where the generated heat in nitrobenzene hydrogenation reaction transfers to Naphtha reforming reaction medium through the surface of the tube. A steady-state, homogeneous, two-dimensional model is used to describe the performance of this configuration and a kinetic model including 32 pseudo-components with 84 reactions is considered for Naphtha reforming reaction. After validating the model with the commercial data of a domestic plant, the obtained results of coupled reactor are compared by the conventional one. The obtained results show the superiority of CCR coupled reactor against the conventional one.
S Alkhattaf - One of the best experts on this subject based on the ideXlab platform.
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catalytic cracking of crude oil to light olefins and Naphtha experimental and kinetic modeling
Chemical Engineering Research & Design, 2017Co-Authors: A Usman, Abdul Bari M Siddiqui, Abdelrahman I Hussain, Abdullah M Aitani, S AlkhattafAbstract:Abstract The direct catalytic cracking of three light crude oils have been evaluated over an equilibrated FCC catalyst (E-Cat) blended with MFI zeolite in a microactivity test unit at 550 °C and catalyst/oil ratio between 1 to 4. At 60% conversion, the Super Light (ASL) crude oil yielded about 10 wt.% C 2 –C 4 olefins and 60 wt.% Naphtha over E-Cat, Extra Light (AXL) crude oil yielded 13 wt.% light olefins and 52 wt.% Naphtha, while for Arab Light (AL) crude oil, light olefins and Naphtha produced were 12 and 51 wt.%, respectively. The addition of MFI with varying Si/Al molar ratio (Z30, Z280 and Z1500) to E-Cat increased the yield of light olefins with a maximum at 21.3 wt.% for AXL over E-Cat/Z280. PIONA analysis of co-produced Naphtha showed an increase in aromatics content over all additives with a maximum obtained from the cracking of AL over Z30 (91 wt.%). Steam treatment of Z280 led to a slight change in the yield of light olefins and reduction of Naphtha aromatics for the three types of crude oils. A four-lump kinetic model accurately predicted experimental yields of AL cracking over E-Cat and E-Cat/Z280 between 500 °C and 550 °C. From the kinetic model, the apparent activation energy for the conversion of Naphtha to gases decreased from 21.2 kcal/mol over E-Cat to 16.2 kcal/mol over E-Cat/Z280 which indicates that Z280 facilitated the increased cracking of Naphtha-range species to light olefins
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enhancing the production of light olefins by catalytic cracking of fcc Naphtha over mesoporous zsm 5 catalyst
Topics in Catalysis, 2010Co-Authors: M Bari A Siddiqui, M Saeed, Abdullah M Aitani, S AlkhattafAbstract:The enhanced production of light olefins from the catalytic cracking of FCC Naphtha was investigated over a mesoporous ZSM-5 (Meso-Z) catalyst. The effects of acidity and pore structure on conversion, yields and selectivity to light olefins were studied in microactivity test (MAT) unit at 600 °C and different catalyst-to-Naphtha (C/N) ratios. The catalytic performance of Meso-Z catalyst was compared with three conventional ZSM-5 catalysts having different SiO2/Al2O3 (Si/Al) ratios of 22 (Z-22), 27 (Z-27) and 150 (Z-150). The yields of propylene (16 wt%) and ethylene (10 wt%) were significantly higher for Meso-Z compared with the conventional ZSM-5 catalysts. Almost 90% of the olefins in the FCC Naphtha feed were converted to lighter olefins, mostly propylene. The aromatics fraction in cracked Naphtha almost doubled in all catalysts indicating some level of aromatization activity. The enhanced production of light olefins for Meso-Z is attributed to its small crystals that suppressed secondary and hydrogen transfer reactions and to its mesopores that offered easier transport and access to active sites.
A Mohamadalizadeh - One of the best experts on this subject based on the ideXlab platform.
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optimization and deactivation study of fe ce hzsm 5 catalyst in steam catalytic cracking of mixed ethanol Naphtha feed
Journal of Analytical and Applied Pyrolysis, 2013Co-Authors: Ali Zeinali Varzaneh, Jafar Towfighi, Amir Hossein Shahbazi Kootenaei, A MohamadalizadehAbstract:Abstract Mixed iron and cerium oxide supported on HZSM-5 was utilized in steam catalytic cracking of Naphtha diluted with ethanol at 650 °C. The effect of Fe (0.8–3 wt%) and Ce (2.5–8 wt%) loading and addition of ethanol to Naphtha (ethanol concentration = 10–30 wt%) was studied using central composite design and optimized using Response Surface Methodology (RSM). The Analysis of Variance (ANOVA) utilized for investigating the significance of independent factors and quadratic interactions between them demonstrated that ethanol concentration was the most significant factor. The multiobjective optimization of ethylene and propylene yields was found at Fe, Ce, and ethanol equal to 1.97, 6.36, and 22.03 wt%, respectively. The corresponding yield values for ethylene and propylene were estimated being 32.79 and 18.05 wt%, respectively. Deactivation of 1.9%Fe-5.25%Ce/HZSM-5 catalyst was studied over 8 h on-stream over an ethanol-free and ethanol containing Naphtha feed. Deactivation tests showed lifetime enhancement for catalysts exposed to the Naphtha diluted with ethanol. Fresh and used catalysts were characterized by XRD, BET, TGA, and FT-IR techniques.
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investigating the effect of key factors their interactions and optimization of Naphtha steam cracking by statistical design of experiments
Journal of Analytical and Applied Pyrolysis, 2010Co-Authors: Kamyar Keyvanloo, Jafar Towfighi, Seyed Mojtaba Sadrameli, A MohamadalizadehAbstract:The effect of temperature, steam-to-Naphtha ratio, and residence time and their quadratic and cubic interactions on the yield of light olefins (ethylene and propylene) in Naphtha steam cracking has been investigated. The temperature, steam-to-Naphtha ratio, and residence time were varied in the range 1053–1153 K, 0.5–0.9 g/g, and 0.15–0.4 s, respectively. Based on the experimental results, Naphtha steam cracking was modeled by use of statistical design of experiments (DoE). The results for the successful multiobjective optimization (MOO) of the Naphtha steam cracking have also been reported. The new developed model is employed for the optimization purposes. Two MOO problems are solved; these problems involved maximization of ethylene, propylene and selectivity and minimization of severity. The response defined by the three most significant parameters was obtained from full factorial design and the optimal parameter set was found. The superiority of the DoE method over the conventional change one separate factor at a time approach is shown by the fact that we were able to study the higher interactions and optimize three individual factors with only 27 runs.
Davood Iranshahi - One of the best experts on this subject based on the ideXlab platform.
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modeling of Naphtha reforming unit applying detailed description of kinetic in continuous catalytic regeneration process
Chemical Engineering Research & Design, 2014Co-Authors: Davood Iranshahi, Mohsen Karimi, Shahram Amiri, Mitra Jafari, Razieh Rafiei, M R RahimpourAbstract:Abstract Naphtha reforming is one of the most important processes in refineries in which high value-added reformate for gasoline pool and aromatics such as benzene, toluene, and xylene are produced. It is necessary to establish new Naphtha reforming units and develop the traditional units to increase the efficiency of the processes. In this study, according to the recent progresses in the Naphtha reforming technology, mathematical modeling of this process in continuous catalyst regeneration mode of operation is accomplished in two dimensions (radial and axial) by considering cross flow pattern. In addition, a new catalyst deactivation model has been proposed and a new reaction network model based on 32 pseudo-components with 84 reactions is investigated. Then, this model has been validated by comparing with industrial data, and its results have acceptable agreement.
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progress in catalytic Naphtha reforming process a review
Applied Energy, 2013Co-Authors: M R Rahimpour, Mitra Jafari, Davood IranshahiAbstract:Catalytic Naphtha reforming process is a vital process for refineries due to the production of high-octane components, which is intensely demanded in our modern life. The significance of this industrial process induced researchers to investigate different aspects of catalytic Naphtha reforming process intensively. Some of the investigators try to improve this process by representing more effective catalysts, while others try to elucidate its kinetic and deactivation mechanisms and design more efficient reactor setups. The amount of these established papers is so much that may confuse some of the researchers who want to find collective information about catalytic Naphtha reforming process. In the present paper, the published studies from 1949 until now are categorized into three main groups including finding suitable catalyst, revealing appropriate kinetic and deactivation model, and suggesting efficient reactor configuration and mode of operation. These studies are reviewed separately, and a suitable reference is provided for those who want to have access to generalized information about catalytic Naphtha reforming process. Finally, various suggestions for revamping the catalytic Naphtha reforming process have been proposed as a guideline for further investigations.
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combining continuous catalytic regenerative Naphtha reformer with thermally coupled concept for improving the process yield
International Journal of Hydrogen Energy, 2013Co-Authors: Mitra Jafari, Davood Iranshahi, Mohsen Karimi, Shahram Amiri, Razieh Rafiei, M R Rahimpour, Hojjat MahdiyarAbstract:Abstract Advancements in the catalytic Naphtha reforming process, as one of the main processes in petrochemical industry, contributed to development of continuous catalytic regenerative Naphtha reformer units. Increasing the yield of aromatic and hydrogen as well as saving the energy in this process through the application of thermal coupling technique is a potentially interesting idea. This novel idea has been assessed in this paper. In the proposed configuration, continuous catalyst regeneration Naphtha reforming process is coupled with hydrogenation of nitrobenzene in a two co-axial reactor separated by a solid wall, where the generated heat in nitrobenzene hydrogenation reaction transfers to Naphtha reforming reaction medium through the surface of the tube. A steady-state, homogeneous, two-dimensional model is used to describe the performance of this configuration and a kinetic model including 32 pseudo-components with 84 reactions is considered for Naphtha reforming reaction. After validating the model with the commercial data of a domestic plant, the obtained results of coupled reactor are compared by the conventional one. The obtained results show the superiority of CCR coupled reactor against the conventional one.
