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Pablo J Miguel - One of the best experts on this subject based on the ideXlab platform.

  • im 5 zeolite for steam Catalytic Cracking of naphtha to produce propene and ethene an alternative to zsm 5 zeolite
    Applied Catalysis A-general, 2013
    Co-Authors: Avelino Corma, Jesus Mengual, Pablo J Miguel
    Abstract:

    Abstract Steam Catalytic Cracking of naphtha in smaller FCC units can be considered an option to produce more ethene and propene. These units will operate at high reaction temperatures and in the presence of steam. The profitability of these units could be improved with the use of new catalysts with higher activity and hydrothermal stability, without compromising the selectivity to light olefins. We have explored the possibilities of IM-5 zeolite for high temperature steam Catalytic Cracking (SCC) of a naphtha, as an alternative to commonly used ZSM-5 zeolite. So, we compare the Catalytic activity, the effect of operating variables of the process and the yields of interest products between the two zeolites, the IM-5 zeolite and the best of ZSM-5 zeolites studied previously for SCC reaction. Furthermore, we study post-synthesis treatment of zeolite with phosphorous containing precursors to enhance the hydrothermal stability, and the effect of it on the Catalytic activity and the yield of products. It can be seen as the use of the zeolite proposal improve the Catalytic activity with respect to the best of ZSM-5 zeolite in SCC process, without compromising the yield to products of interest. Furthermore, the incorporation of phosphorous has a large effect on hydrothermal stability of zeolite, showing this zeolite as an important competitor to the ZSM-5 zeolite for steam Catalytic Cracking of naphtha.

  • steam Catalytic Cracking of naphtha over zsm 5 zeolite for production of propene and ethene micro and macroscopic implications of the presence of steam
    Applied Catalysis A-general, 2012
    Co-Authors: Avelino Corma, Jesus Mengual, Pablo J Miguel
    Abstract:

    Abstract One option to produce more ethene and propene can be to crack naphtha type fractions in dedicated smaller FCC units. We present here the results obtained for high temperature steam Catalytic Cracking (SCC) of a representative naphtha product ( n -heptane) with ZSM-5. It has been found that under those conditions the presence of steam produces an irreversible dealumination of the zeolite as well as a reversible deactivation due to the interaction of water with active sites with a negative effect on protolytic Cracking. A kinetic decay model that takes into account the two phenomena has been developed. The apparent activation energy is lower in the presence of steam. It appears that whilst the presence of steam is vital when processing heavy feeds to achieve a better feed dispersion and a more effective Catalytic Cracking in conventional fluid Catalytic Cracking (FCC) units, in the case of steam Catalytic Cracking of naphtha ( n -heptane) the presence of steam has a negative effect on the final performance of the catalyst. On the other hand, whilst steam does not modify ethene and propene selectivity, significantly decreases H 2 and CH 4 formation, as well as formation of potential coke precursors.

Jinsen Gao - One of the best experts on this subject based on the ideXlab platform.

N C Markatos - One of the best experts on this subject based on the ideXlab platform.

  • simulation and design of fluid Catalytic Cracking riser type reactors
    Aiche Journal, 1997
    Co-Authors: K N Theologos, I D Nikou, A I Lygeros, N C Markatos
    Abstract:

    Two-phase flow, heat transfer, and reaction in fluid Catalytic-Cracking riser-type reactors are studied using a 3-D mathematical model. This study was carried out based on the model of Theologos and Markatos, which incorporates a detailed ten-lump reaction kinetics scheme and accounts for gradual feedstock vaporization inside the reactor. Predictions obtained using the new model are compared against industrial reactor operating data. A design study was also carried out to illustrate that the model developed is capable of predicting feed-injector geometry effects on overall reactor performance. It shows that by increasing the number of feed-injection operating nozzles at the bottom of the reactor, selectivity of primary products is improved.

  • simulation and design of fluid Catalytic Cracking riser type reactors
    Computers & Chemical Engineering, 1996
    Co-Authors: K N Theologos, I D Nikou, A I Lygeros, N C Markatos
    Abstract:

    Abstract Two-phase flow, heat transfer and reaction in Fluid Catalytic Cracking riser-type reactors is studied using 3-D Computational Fluid Dynamics techniques. A model already presented in the literature (Theologos and Markatos, 1993) is further developed to incorporate a detailed 10-lump reaction kinetics scheme and account for feedstock gradual vaporization inside the reactor. A design study is carried out to illustrate that developed model is capable of predicting feed injector geometry effects on overall reactor performance. It is predicted that, by increasing the number of feed injection operating nozzles at the bottom of the reactor, selectivity to primary products is improved.

Avelino Corma - One of the best experts on this subject based on the ideXlab platform.

  • im 5 zeolite for steam Catalytic Cracking of naphtha to produce propene and ethene an alternative to zsm 5 zeolite
    Applied Catalysis A-general, 2013
    Co-Authors: Avelino Corma, Jesus Mengual, Pablo J Miguel
    Abstract:

    Abstract Steam Catalytic Cracking of naphtha in smaller FCC units can be considered an option to produce more ethene and propene. These units will operate at high reaction temperatures and in the presence of steam. The profitability of these units could be improved with the use of new catalysts with higher activity and hydrothermal stability, without compromising the selectivity to light olefins. We have explored the possibilities of IM-5 zeolite for high temperature steam Catalytic Cracking (SCC) of a naphtha, as an alternative to commonly used ZSM-5 zeolite. So, we compare the Catalytic activity, the effect of operating variables of the process and the yields of interest products between the two zeolites, the IM-5 zeolite and the best of ZSM-5 zeolites studied previously for SCC reaction. Furthermore, we study post-synthesis treatment of zeolite with phosphorous containing precursors to enhance the hydrothermal stability, and the effect of it on the Catalytic activity and the yield of products. It can be seen as the use of the zeolite proposal improve the Catalytic activity with respect to the best of ZSM-5 zeolite in SCC process, without compromising the yield to products of interest. Furthermore, the incorporation of phosphorous has a large effect on hydrothermal stability of zeolite, showing this zeolite as an important competitor to the ZSM-5 zeolite for steam Catalytic Cracking of naphtha.

  • steam Catalytic Cracking of naphtha over zsm 5 zeolite for production of propene and ethene micro and macroscopic implications of the presence of steam
    Applied Catalysis A-general, 2012
    Co-Authors: Avelino Corma, Jesus Mengual, Pablo J Miguel
    Abstract:

    Abstract One option to produce more ethene and propene can be to crack naphtha type fractions in dedicated smaller FCC units. We present here the results obtained for high temperature steam Catalytic Cracking (SCC) of a representative naphtha product ( n -heptane) with ZSM-5. It has been found that under those conditions the presence of steam produces an irreversible dealumination of the zeolite as well as a reversible deactivation due to the interaction of water with active sites with a negative effect on protolytic Cracking. A kinetic decay model that takes into account the two phenomena has been developed. The apparent activation energy is lower in the presence of steam. It appears that whilst the presence of steam is vital when processing heavy feeds to achieve a better feed dispersion and a more effective Catalytic Cracking in conventional fluid Catalytic Cracking (FCC) units, in the case of steam Catalytic Cracking of naphtha ( n -heptane) the presence of steam has a negative effect on the final performance of the catalyst. On the other hand, whilst steam does not modify ethene and propene selectivity, significantly decreases H 2 and CH 4 formation, as well as formation of potential coke precursors.

  • on the mechanism of sulfur removal during Catalytic Cracking
    Applied Catalysis A-general, 2001
    Co-Authors: Avelino Corma, Cristina Martinez, G Ketley, G Blair
    Abstract:

    A low sulfur vacuum gas oil (VGO) has been spiked with sulfur containing compounds belonging to the gasoline and light diesel range, and the feedstocks obtained in this way have been cracked over an equilibrated catalyst in an automated MAT unit. The evolution of these sulfur compounds under Catalytic Cracking conditions has been studied using a specific sulfur detector. The reactivity of the sulfur compounds as well as their interaction with olefins and naphthenic compounds has been elucidated.

Zhanjun Cheng - One of the best experts on this subject based on the ideXlab platform.

  • co upgrading of raw bio oil with kitchen waste oil through fluid Catalytic Cracking fcc
    Applied Energy, 2018
    Co-Authors: Bin Liu, Ruixue Zhang, Lei Zhong, Guanyi Chen, Zhanjun Cheng
    Abstract:

    Abstract Raw bio-oil was produced from fast pyrolysis of pine sawdust in a fluidized-bed boiler at 550 °C. Then the raw bio-oil is partially mixed with kitchen waste oil (100:0, 50:50, 0:100 by weight) and subsequently subjected to off line co-Catalytic Cracking process for upgrading over HZSM-5. The raw bio-oil mixed with kitchen waste oil test shows that the co-Catalytic Cracking improves the organic bio-oil yield and inhibits the coke formation. The oxygen content of organic bio-oil decreased significantly after upgrading. The reaction pathway of co-upgrading is proposed, which shows that kitchen waste oil, as a hydrogen supplier, transform hydrogen from high saturation degree to the unsaturation oxygenated compounds to form hydrocarbons. Co-Catalytic Cracking process of raw bio-oil and kitchen waste oil not only can be used in raw bio-oil upgrading but also can recycle kitchen waste oil with relatively low cost. Moreover, the deactivation catalysts are analyzed by TG-FTIR (Thermogravimetric-Fourier Transform Infrared spectroscopy) and SEM (Scanning Electron Microscope).