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Jean-alain Dalmon - One of the best experts on this subject based on the ideXlab platform.
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Selective oxidation of butane to maleic anhydride in a catalytic membrane Reactor adapted to rich butane feed
Catalysis Today, 2005Co-Authors: Arquímedes Cruz-lópez, Sylvain Miachon, Nolven Guilhaume, Jean-alain DalmonAbstract:Abstract The n -butane selective oxidation has been studied in a membrane Reactor, using high butane concentrations. Thanks to the oxygen distribution by the membrane, it is possible to keep the local composition outside the flammability zone. A MFI ceramic membrane was used to distribute oxygen (or part of it) in the catalyst bed, made of a VPO mixed oxide, either Conventional or Co-doped. In a first step, the effect of the oxygen distribution has been studied, showing that, under standard reactant mixtures (O 2 /butane = 12, low butane concentration), the membrane Reactor performed very close to the Conventional one. Under high butane concentrations, the VPO system suffered from a drastic decrease of the selectivity towards maleic anhydride (MA). The addition of cobalt to the VPO catalyst allowed keeping the MA selectivity at a high level (75%). The combination of the CoVPO catalyst and the MFI membrane was used to explore the membrane Reactor performance with high butane concentrations in the feed, corresponding to the flammability zone in a Conventional Reactor. For these conditions, the MA productivity was three times higher than that observed with the Conventional Reactor.
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Xylene isomerization in an extractor type Catalytic Membrane Reactor
Catalysis Today, 2005Co-Authors: Lizelle Van Dyk, Leon Lorenzen, Sylvain Miachon, Jean-alain DalmonAbstract:Abstract A zeolite/alumina pore plugging membrane was used to successfully separate xylene isomers. It was then applied, as a selective membrane, in an extractor type catalytic membrane Reactor (CMR), used to enhance the xylene isomerization reaction selectivity towards para-xylene. The results of the CMR in different configurations (permeate-only and combined permeate-and-retentate mode) were compared to Conventional fixed-bed Reactor results. In both cases, the selectivity was significantly enhanced (up to 100% in permeate-only mode). In the combined mode, the CMR also provided a net increase in productivity over the Conventional Reactor.
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Xylene isomerization in an extractor type Catalytic Membrane Reactor
Catalysis Today, 2005Co-Authors: Lizelle Van dyk, Leon Lorenzen, Sylvain Miachon, Jean-alain DalmonAbstract:A zeolite / alumina pore plugging membrane was used to successfully separate xyleneisomers. It was then applied as a selective membrane in an extractor type CatalyticMembrane Reactor (CMR), used to enhance the xylene isomerization reaction selectivity towards para-xylene. The results of the CMR in different configurations (permeate-onlyand combined permeate-&-retentate mode) were compared to Conventional Reactorresults. In both cases, the selectivity was significantly enhanced (up to 100% in permeateonly mode). In combined mode, the CMR also provided a net increase in productivityover the Conventional Reactor.
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Isobutane dehydrogenation in a membrane Reactor: Influence of the operating conditions on the performance
Catalysis Today, 2001Co-Authors: P. Ciavarella, Sylvain Miachon, D. Casanave, K. Fiaty, Hichem Moueddeb, Jean-alain DalmonAbstract:Abstract Isobutane dehydrogenation has been investigated in a membrane Reactor combining a bimetallic PtIn/zeolite fixed-bed catalyst and a microporous MFI-alumina tubular membrane. The membrane Reactor performance has been studied as a function of the feed and sweep flow rates and of the sweep (co- or counter-current sweep modes). Isobutene yields up to four times higher than that observed in a Conventional Reactor have been obtained. Depending on the conditions, it is shown that the performance of the membrane Reactor is controlled either by the membrane or by the catalyst.
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Computer-aided optimisation of catalytic dehydrogenation in packed-bed membrane Reactor
Computers & Chemical Engineering, 1998Co-Authors: D. Casanave, K. Fiaty, Jean-alain DalmonAbstract:Catalytic membrane Reactors offer the opportunity to combine chemical reaction with the separation activity of the membrane in one unit operation. In order to determine suitable operating conditions, numerical simulations are performed and results obtained are compared to results from Conventional Reactor. The effects of the inner compartment radius and the Reactor length are also investigated. The chemical reaction studied is the catalytic dehydrogenation of isobutane.
Kai Sundmacher - One of the best experts on this subject based on the ideXlab platform.
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miniplant scale evaluation of a semibatch continuous tandem Reactor system for the hydroformylation of long chain olefins
Industrial & Engineering Chemistry Research, 2019Co-Authors: Michael Jokiel, Karsten Ratze, Nicolas Maximilian Kaiser, Kai U Kunnemann, Janpeter Hollenbeck, Jens M Dreimann, Dieter Vogt, Kai SundmacherAbstract:Innovative Reactor concepts show evidence to significantly improve the reaction performance in comparison to Conventional Reactor systems. To evaluate the Reactor concepts, experimental investigati...
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miniplant scale evaluation of a semibatch continuous tandem Reactor system for the hydroformylation of long chain olefins
Industrial & Engineering Chemistry Research, 2019Co-Authors: Michael Jokiel, Karsten Ratze, Nicolas Maximilian Kaiser, Kai U Kunnemann, Janpeter Hollenbeck, Jens M Dreimann, Dieter Vogt, Kai SundmacherAbstract:Innovative Reactor concepts show evidence to significantly improve the reaction performance in comparison to Conventional Reactor systems. To evaluate the Reactor concepts, experimental investigation of the process behavior is indispensable. In this contribution, a Reactor tandem comprising a repeatedly operated semibatch Reactor (RSBR) followed by a continuously stirred tank Reactor (CSTR) is analyzed for the hydroformylation of 1-dodecene. This Reactor tandem was suggested by N. M. Kaiser et al. [Ind. Eng. Chem. Res. 2017, 56, 11507–11518] to increase the selectivity toward the linear aldehyde at high conversion levels of 1-dodecene. An additional degree of freedom is gained because of the combined utilization of a batchwise and continuously operated Reactor. By using a dynamic process model for planning of the experiments, comparability is ensured with studies of a single CSTR from literature. The experiments confirm an increase in conversion and target product yield applying the RSBR + CSTR tandem, so...
Sylvain Miachon - One of the best experts on this subject based on the ideXlab platform.
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Selective oxidation of butane to maleic anhydride in a catalytic membrane Reactor adapted to rich butane feed
Catalysis Today, 2005Co-Authors: Arquímedes Cruz-lópez, Sylvain Miachon, Nolven Guilhaume, Jean-alain DalmonAbstract:Abstract The n -butane selective oxidation has been studied in a membrane Reactor, using high butane concentrations. Thanks to the oxygen distribution by the membrane, it is possible to keep the local composition outside the flammability zone. A MFI ceramic membrane was used to distribute oxygen (or part of it) in the catalyst bed, made of a VPO mixed oxide, either Conventional or Co-doped. In a first step, the effect of the oxygen distribution has been studied, showing that, under standard reactant mixtures (O 2 /butane = 12, low butane concentration), the membrane Reactor performed very close to the Conventional one. Under high butane concentrations, the VPO system suffered from a drastic decrease of the selectivity towards maleic anhydride (MA). The addition of cobalt to the VPO catalyst allowed keeping the MA selectivity at a high level (75%). The combination of the CoVPO catalyst and the MFI membrane was used to explore the membrane Reactor performance with high butane concentrations in the feed, corresponding to the flammability zone in a Conventional Reactor. For these conditions, the MA productivity was three times higher than that observed with the Conventional Reactor.
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Xylene isomerization in an extractor type Catalytic Membrane Reactor
Catalysis Today, 2005Co-Authors: Lizelle Van Dyk, Leon Lorenzen, Sylvain Miachon, Jean-alain DalmonAbstract:Abstract A zeolite/alumina pore plugging membrane was used to successfully separate xylene isomers. It was then applied, as a selective membrane, in an extractor type catalytic membrane Reactor (CMR), used to enhance the xylene isomerization reaction selectivity towards para-xylene. The results of the CMR in different configurations (permeate-only and combined permeate-and-retentate mode) were compared to Conventional fixed-bed Reactor results. In both cases, the selectivity was significantly enhanced (up to 100% in permeate-only mode). In the combined mode, the CMR also provided a net increase in productivity over the Conventional Reactor.
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Xylene isomerization in an extractor type Catalytic Membrane Reactor
Catalysis Today, 2005Co-Authors: Lizelle Van dyk, Leon Lorenzen, Sylvain Miachon, Jean-alain DalmonAbstract:A zeolite / alumina pore plugging membrane was used to successfully separate xyleneisomers. It was then applied as a selective membrane in an extractor type CatalyticMembrane Reactor (CMR), used to enhance the xylene isomerization reaction selectivity towards para-xylene. The results of the CMR in different configurations (permeate-onlyand combined permeate-&-retentate mode) were compared to Conventional Reactorresults. In both cases, the selectivity was significantly enhanced (up to 100% in permeateonly mode). In combined mode, the CMR also provided a net increase in productivityover the Conventional Reactor.
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comparison of a contactor catalytic membrane Reactor with a Conventional Reactor example of wet air oxidation
Catalysis Today, 2003Co-Authors: Sylvain Miachon, Victor Perez, Gabriel Crehan, Eddy Torp, Henrik Raeder, Rune Bredesen, J A DalmonAbstract:Abstract A wet air oxidation reaction was carried out in a gas/liquid catalytic membrane Reactor of the contactor type. The oxidation of formic acid was used as a model reaction. The mesoporous top-layer of a ceramic tubular membrane was used as catalyst (Pt) support, and was placed at the interface of the gas (air) and liquid (HCOOH solution) phases. A similar reaction was carried out in a Conventional batch Reactor, using a steering rate high enough to avoid gas-diffusion limitations, and exactly identical conditions than for the CMR (amount of catalyst, pressure, etc.). At room temperature, the CMR showed an initial activity three to six times higher than the Conventional Reactor. This activity increase was attributed to an easier oxygen access to the catalytic sites. Nevertheless, the catalytic membrane gradually deactivated after a few hours of operation. Different deactivation mechanisms are presented.
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Isobutane dehydrogenation in a membrane Reactor: Influence of the operating conditions on the performance
Catalysis Today, 2001Co-Authors: P. Ciavarella, Sylvain Miachon, D. Casanave, K. Fiaty, Hichem Moueddeb, Jean-alain DalmonAbstract:Abstract Isobutane dehydrogenation has been investigated in a membrane Reactor combining a bimetallic PtIn/zeolite fixed-bed catalyst and a microporous MFI-alumina tubular membrane. The membrane Reactor performance has been studied as a function of the feed and sweep flow rates and of the sweep (co- or counter-current sweep modes). Isobutene yields up to four times higher than that observed in a Conventional Reactor have been obtained. Depending on the conditions, it is shown that the performance of the membrane Reactor is controlled either by the membrane or by the catalyst.
Mohammad Reza Rahimpour - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous production of xylenes and hydrogen in an optimized membrane-assisted thermally coupled Reactor using an elaborate reaction network
Chemical Engineering and Processing: Process Intensification, 2017Co-Authors: Nazanin Hamedi, Sara Masoumi, Mahshid Nategh, Mohammad Reza RahimpourAbstract:Abstract In this paper, an optimized membrane-assisted thermally coupled Reactor, as well-known equipment for process intensification (PI), is proposed for simultaneous production of highly-valuable xylenes and pure hydrogen. In the proposed configuration, transalkylation process (exothermic reaction) and dehydrogenation of methylcyclohexane (endothermic reaction) take place simultaneously in two different sides, and a hydrogen perm-selective Pd/Ag membrane is utilized to separate pure hydrogen from the endothermic side. A comprehensive reaction network is applied for the exothermic side with the aim of providing a reliable Reactor model. The operating conditions of the membrane-assisted thermally coupled Reactor are optimized using Differential Evolution (DE) method with 10 decision variables. The model results of Conventional Reactor are validated with the plant data and a reasonable agreement is achieved. In order to verify the performance of the membrane-assisted thermally coupled Reactor configuration, the modeling results are compared with that of the Conventional Reactor, which reveals that the optimized thermally coupled membrane Reactor results in more xylenes yield and lower temperature in exothermic side.
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Mathematical modeling and optimization of DME synthesis in two spherical Reactors connected in series
Journal of Natural Gas Science and Engineering, 2014Co-Authors: Fereshteh Samimi, M. Bayat, Mohammad Reza Rahimpour, Peyman KeshavarzAbstract:Abstract Due to some disadvantages of Conventional tubular Reactors, spherical Reactors attract more attentions. In the present study, dimethyl ether (DME) synthesis by dehydration of methanol is considered in two-stage axial flow, spherical packed bed Reactors connected in series. The catalyst volume in the Conventional Reactor (CR) is divided into two sections to pack spherical Reactors. In this novel configuration, the unreacted methanol from the first Reactor passes through a heat exchanger to reach to a desire temperature and then enters top of the second Reactor as the inlet feed. In fact in this study, the unused catalyst in the Conventional Reactor is used efficiently in the second spherical Reactor of the proposed configuration to produce more DME by dehydration of unreacted methanol from the first Reactor. The inlet temperatures as well as the catalyst distributions for each Reactor in this configuration are optimized using differential evolution (DE) method to maximize the outlet DME production rate. Then the optimization results are compared with the Conventional one. The results show that, 3153 ton/day DME is produced, which is a gain of 16.3% over a Conventional Reactor, using the same catalyst loading and duty.
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Sorption-enhanced Fischer–Tropsch synthesis with continuous adsorbent regeneration in GTL technology: Modeling and optimization
Journal of Industrial and Engineering Chemistry, 2014Co-Authors: M. Bayat, M. Hamidi, Z. Dehghani, Mohammad Reza RahimpourAbstract:Abstract Fischer–Tropsch synthesis (FTS) plays an important role in the production of clean liquid transportation fuels, chemicals, and other hydrocarbon products. This work proposes a novel configuration of FTS Reactor in which zeolite 4A, with the composition of Na12(Si12Al12O48)·27H2O, is considered as water adsorbent. For this purpose, a gas-flowing solids-fixed bed Reactor (GFSFBR) is used instead of Conventional Reactor. The main advantage of GFSFBR over the Conventional sorption-enhanced reaction process is the continuous adsorbent regeneration in this novel configuration. Simulation result demonstrates that selective adsorption of water from FTS in GFSFBR leads to significant enhancement in the gasoline yield and reduction in CO2 production in comparison with the zero solid mass flux condition. Subsequently, the aforementioned Reactor is optimized using differential evolution (DE) algorithm as an effective and robust optimization method. Optimization results show that there are optimum values for eight decision variables under which the highest gasoline productivity can be achieved. Afterwards, the simulation and optimization results are compared with the ones in Conventional Reactor. This paper shows how the concept of in situ water adsorption is feasible and beneficial for FTS.
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Genetic algorithm strategy (GA) for optimization of a novel dual-stage slurry bubble column membrane configuration for Fischer–Tropsch synthesis in gas to liquid (GTL) technology
Journal of Natural Gas Science and Engineering, 2011Co-Authors: M. Bayat, Mohammad Reza Rahimpour, Behdad MoghtaderiAbstract:Abstract In this work, a novel configuration of a cascade double membrane assisted slurry bubble column Reactor and hydrogen-permselective membrane Reactor is proposed (SDMR) for Fischer–Tropsch synthesis (FTS). A one-dimensional heterogeneous model in first Reactor and axial dispersion model (AMD) for both gas and liquid–solid suspension as a homogeneous phase for slurry bubble column Reactor has been developed. Subsequently, this novel configuration was optimized. Here, genetic algorithm (GA) method was applied as powerful method for optimization of procedure. The proposed model has been used to compare the performance of an SDMR with a Fluidized-bed membrane dual-type Reactor (FMDR) and a Conventional Reactor (CR). The simulation results show an enhancement in the gasoline production, a main decrease in undesirable product formation and a favorable temperature profile along the proposed concept rather than Conventional Reactor and even FMDR.
Chang Yeol Yu - One of the best experts on this subject based on the ideXlab platform.
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Study on a catalytic membrane Reactor for hydrogen production from ethanol steam reforming
International Journal of Hydrogen Energy, 2009Co-Authors: Chang Yeol Yu, Sang-jun ParkAbstract:Abstract Ethanol steam reforming in a membrane Reactor with catalytic membranes was investigated to achieve important aims in one process, such as improvement in ethanol conversion and hydrogen yield, high hydrogen recovery and CO reduction. In order to confirm the efficiency of reaction and CO reduction, an ethanol reforming-catalytic membrane Reactor with water–gas shift reaction (ECRW) in the permeate side was compared with a Conventional Reactor (CR) and an ethanol reforming-catalytic membrane Reactor (ECR). In comparison with the CR, ethanol conversion improvement of 11.9–19% and high hydrogen recovery of 78–87% were observed in the temperature range of 300–600 °C in the ECRW. Compared with CR and ECR, the hydrogen yield of ECRW increased up to 38% and 30%, respectively. Particularly, the ECRW showed higher hydrogen yield at high temperature, because Pt/Degussa P25 loaded in the permeate side showed catalytic activity for the methane steam reforming as well as WGS reaction. Moreover, CO concentration was reduced under 1% by the WGS reaction in the permeate side in the temperature range of 300–500 °C.
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Hydrogen production from a DME reforming-membrane Reactor using stainless steel-supported Knudsen membranes with high permeability
Journal of Membrane Science, 2008Co-Authors: Sang-jun Park, Chang Yeol YuAbstract:Abstract Stainless steel-supported composite membranes with the Knudsen-dominated permeation behavior were synthesized via the dipping–rolling–freezing–fast drying (DRFF) and soaking–rolling–freezing–fast drying (SRFF) method. A dimethyl ether (DME) steam reforming was performed in a membrane Reactor using the stainless steel-supported Knudsen membrane (SKM) with remarkably high permeability. The Knudsen membrane with high permeability was used to improve DME conversion and hydrogen recovery. Compared to a Conventional Reactor, the DME conversion was improved up to 48% and the hydrogen recovery was 37–38% in the temperature range of 250–450 °C. Moreover, the DME steam reforming-membrane Reactor was combined with water–gas shift (WGS) reaction in the permeate side of the membrane Reactor to obtain high CO removal efficiency. As a result, the CO concentrations was significantly reduced to below 20 ppm in the permeate side of the membrane Reactor via the WGS reaction in the temperature range of 300–450 °C.
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Dimethyl Ether Reforming in a Mesoporous γ-Alumina Membrane Reactor Combined with a Water Gas Shift Reaction
Industrial & Engineering Chemistry Research, 2008Co-Authors: Sang-jun Park, Chang Yeol YuAbstract:Dimethyl ether (DME) steam reforming was performed in a γ-alumina/silica/stainless steel composite membrane Reactor combined with a water gas shift (WGS) reaction to achieve three important aims simultaneously, such as DME conversion improvement, high hydrogen recovery, and CO elimination. The Knudsen membrane with high permeability was used to increase conversion improvement and hydrogen recovery. In one process of the DME steam reforming membrane Reactor combined with the WGS reaction, the DME conversion was improved up to 35% in comparison with a Conventional Reactor, and hydrogen recovery was about 20%. The CO was not detected in the permeate side of the membrane Reactor. The high CO removal efficiency was obtained from the WGS reaction with the Pt/TiO2 catalyst in the permeate side of the membrane Reactor.