Carbon deposition on a Ni/α-Al2O3 catalyst

1997 ◽  
Vol 61 (2) ◽  
pp. 375-381 ◽  
Author(s):  
A. E. Castro Luna ◽  
A. M. Becerra
Processes ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 136
Author(s):  
Ourmazd Dehghani ◽  
Mohammad Rahimpour ◽  
Alireza Shariati

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.


2012 ◽  
Vol 198-199 ◽  
pp. 491-502 ◽  
Author(s):  
M.R. Rahimpour ◽  
O. Dehghani ◽  
M.R. Gholipour ◽  
M.S. Shokrollahi Yancheshmeh ◽  
S. Seifzadeh Haghighi ◽  
...  

ACS Omega ◽  
2020 ◽  
Vol 5 (45) ◽  
pp. 28955-28964
Author(s):  
Huanhuan Wang ◽  
Wenlong Mo ◽  
Xiaoqiang He ◽  
Xing Fan ◽  
Fengyun Ma ◽  
...  

2012 ◽  
Vol 102 ◽  
pp. 30-34 ◽  
Author(s):  
Jun-ichi Ozaki ◽  
Masaaki Takei ◽  
Keita Takakusagi ◽  
Nozomi Takahashi

2012 ◽  
Vol 425-426 ◽  
pp. 170-177 ◽  
Author(s):  
Kohji Omata ◽  
Seishiro Kobayashi ◽  
Junpei Horiguchi ◽  
Yasukazu Kobayashi ◽  
Yuichiro Yamazaki ◽  
...  

2011 ◽  
Vol 17 (3) ◽  
pp. 479-483 ◽  
Author(s):  
A.S.A. Al-Fatesh ◽  
A.A. Ibrahim ◽  
A.H. Fakeeha ◽  
A.E. Abasaeed ◽  
M.R.H. Siddiqui

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1376
Author(s):  
Nadezhda S. Smirnova ◽  
Igor S. Mashkovsky ◽  
Pavel V. Markov ◽  
Andrey V. Bukhtiyarov ◽  
Galina N. Baeva ◽  
...  

Local structure of Pd1 single sites on the surface of Pd1In1 intermetallic nanoparticles supported on α-Al2O3 was investigated by the combination of CO-DRIFTS spectroscopy and DFT. CO-DRIFTS spectra of PdIn/Al2O3 catalyst exhibit only one asymmetric absorption band of linearly adsorbed CO comprising two peaks at 2065 and 2055 cm−1 attributable to CO molecules coordinated to Pd1 sites located at (110) and (111) facets of PdIn nanoparticles. The absence of bridged or hollow-bonded CO bands indicates that multipoint adsorption on PdIn nanoparticles is significantly hindered or impossible. DFT results show that on (110) facet multipoint CO adsorption is hindered due to large distance between neighboring Pd atoms (3.35 Å). On (111) facet multipoint CO adsorption on surface palladium atoms is impossible, since adjacent Pd atoms are located below the surface plane.


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