Catalytic functionalities of Pd catalysts supported on spinel MgAl sub(2)O sub(4) for coupling of ethylbenzene dehydrogenation with nitrobenzene hydrogenation

Direct coupling of oxidative dehydrogenation of ethylbenzene with nitrobenzene hydrogenation in a fixed-bed catalytic reactor at atmospheric pressure in the temperature range of 673-823 K over MgAl sub(2)O sub(4)-supported palladium catalysts has been investigated. Simple dehydrogenation of ethylben...

Full description

Saved in:
Bibliographic Details
Published in:Applied petrochemical research 2015-03, Vol.5 (1), p.71-80
Main Authors: Harikrishna, Yengaldas, Pavan Kumar, Vanama, Ramu, Kuna, Chary, Komandur VR, Venkat Rao, Vattikonda
Format: Article
Language:English
Subjects:
Catalysis
Catalysts
Chemisorption
Dehydrogenation
Ethylbenzene
Hydrogenation
Nitrobenzenes
Palladium
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Direct coupling of oxidative dehydrogenation of ethylbenzene with nitrobenzene hydrogenation in a fixed-bed catalytic reactor at atmospheric pressure in the temperature range of 673-823 K over MgAl sub(2)O sub(4)-supported palladium catalysts has been investigated. Simple dehydrogenation of ethylbenzene (DHEB) is reversible, endothermic and thermodynamically limited. The continuous removal of co-produced hydrogen in DHEB for in situ hydrogenation of nitrobenzene over Pd/MgAl sub(2)O sub(4) catalyst improves the performance of the DHEB process. A series of Pd (0.25-4.0 wt%) catalysts supported on MgAl sub(2)O sub(4) was prepared. The catalyst samples were characterized by X-ray diffraction (XRD), H sub(2)-Temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), CO chemisorption, CO sub(2)-Temperature-programmed desorption and BET surface area. Dispersion and particle size of Pd were obtained by CO chemisorption. The reaction profile shows that palladium (0.5 wt%) is an optimum loading to get maximum conversion of ethylbenzene (51.8 %) and nitrobenzene (47.3 %) to give 91.4 and 100 % selectivity of styrene and aniline, respectively.
ISSN:2190-5525
2190-5525
DOI:10.1007/s13203-014-0090-x