The kinetic model of formation of nanofibrous carbon from CH4–H2 mixture over a high-loaded nickel catalyst with consideration for the catalyst deactivation

The current research presents an experimental approach on the mechanism, kinetic and decay of industrial Pd-Ag supported α-Al2O3 catalyst used in the acetylene hydrogenation process. In the first step, the fresh and deactivated hydrogenation catalysts are characterized by XRD, BET (Brunauer–Emmett–Teller), SEM, TEM, and DTG analyses. The XRD results show that the dispersed palladium particles on the support surface experience an agglomeration during the reaction run time and mean particle size approaches from 6.2 nm to 11.5 nm. In the second step, the performance of Pd-Ag supported α-Al2O3 catalyst is investigated in a differential reactor in a wide range of hydrogen to acetylene ratio, temperature, gas hourly space velocity and pressure. The full factorial design method is used to determine the experiments. Based on the experimental results ethylene, ethane, butene, and 1,3-butadiene are produced through the acetylene hydrogenation. In the third step, a detailed reaction network is proposed based on the measured compounds in the product and the corresponding kinetic model is developed, based on the Langmuir-Hinshelwood-Hougen-Watson approach. The coefficients of the proposed kinetic model are calculated based on experimental data. Finally, based on the developed kinetic model and plant data, a decay model is proposed to predict catalyst activity and the parameters of the activity model are calculated. The results show that the coke build-up and condensation of heavy compounds on the surface cause catalyst deactivation at low temperature.

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A kinetic model for leaching process in preparation of Raney nickel catalyst

Industrial & Engineering Chemistry Research ◽

10.1021/ie00085a007 ◽

1989 ◽

Vol 28 (1) ◽

pp. 33-37 ◽

Cited By ~ 11

Author(s):

Vasant R. Choudhary ◽

Sudhakar K. Chaudhari ◽

Ashok N. Gokarn

Keyword(s):

Kinetic Model ◽

Nickel Catalyst ◽

Raney Nickel ◽

Raney Nickel Catalyst ◽

Leaching Process

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Dehalogenation of Chloroarenes with Sodium Dihydridobis(2-methoxyethoxo)aluminate in the Presence of Transition Metal Compounds

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941645 ◽

1994 ◽

Vol 59 (7) ◽

pp. 1645-1653 ◽

Cited By ~ 4

Author(s):

Jaroslav Včelák ◽

Jiří Hetflejš

Keyword(s):

Kinetic Model ◽

Transition Metal ◽

Catalyst Deactivation ◽

Transition Metal Compounds ◽

Metal Species ◽

Metal Compound ◽

Transition Metal Compound ◽

Metal Compounds ◽

First Order

Dehalogenation of low-chlorinated arenes such as p-dichlorobenzene or chlorobenzene with the title hydride is accelerated in the presence of transition metal species formed in situ from the corresponding 2,4-pentanedionates. Their efficiency decreases in the order: Co ≈ Ni ≈ Pd > Cu >> Mn > Fe which results from changes of their activity and stability. The dehalogenation is well described by a kinetic model consisting of the set of dehalogenation steps which are first order in the chloroarene combined with the catalyst deactivation which is second order in the transition metal compound.

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Benzylation of Biphenyl with Benzyl Chloride over HY Zeolites: A Kinetic Model for Reaction and Catalyst Deactivation

Industrial & Engineering Chemistry Research ◽

10.1021/ie970170t ◽

1997 ◽

Vol 36 (9) ◽

pp. 3427-3432 ◽

Cited By ~ 7

Author(s):

Paolo Beltrame ◽

Giovanni Zuretti

Keyword(s):

Kinetic Model ◽

Benzyl Chloride ◽

Catalyst Deactivation ◽

Hy Zeolites

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Nine-lumped kinetic model for VGO catalytic cracking; using catalyst deactivation

Fuel ◽

10.1016/j.fuel.2018.04.126 ◽

2018 ◽

Vol 231 ◽

pp. 118-125 ◽

Cited By ~ 7

Author(s):

Ali Afshar Ebrahimi ◽

Hadis Mousavi ◽

Hamid Bayesteh ◽

Jafar Towfighi

Keyword(s):

Kinetic Model ◽

Catalytic Cracking ◽

Catalyst Deactivation

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Kinetic study of propane aromatization over Zn/HZSM-5 zeolite under conditions of catalyst deactivation using genetic algorithm

Journal of the Serbian Chemical Society ◽

10.2298/jsc170621007r ◽

2018 ◽

Vol 83 (4) ◽

pp. 473-488 ◽

Cited By ~ 1

Author(s):

Abbas Roshanaei ◽

Mehdi Alavi

Keyword(s):

Genetic Algorithm ◽

Kinetic Model ◽

Kinetic Parameters ◽

Catalyst Deactivation ◽

Flow Reactor ◽

Plug Flow ◽

Kinetic Studies ◽

Space Velocity ◽

Propane Aromatization ◽

Aromatization Reaction

The kinetic studies of propane aromatization reaction over Zn/ /HZSM-5 catalyst at temperature of 500?560?C and space velocity of 500?2500 cm3 gcat -1 h-1, in a plug flow reactor, under catalyst deactivating conditions were performed. A lumped kinetic model consisting of six lumped components and six reaction steps was proposed to describe the aromatization of propane. The kinetic model involves 18 kinetic parameters and one catalyst deactivation constant. The reaction steps orders were obtained by the power law model. Frequency factors and the apparent activation energies of the reaction steps were calculated based on the Arrhenius equation. An exponential function depending on the time-on-stream was applied for the catalyst deactivation model and the kinetic parameters were calculated via a genetic algorithm. The kinetic results indicated that the lumped kinetic model can well estimate the product yields of propane aromatization.

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