Dehydrogenation of ethylbenzene to styrene on a direct synthesized Co, Ni/carbon nanotubes catalysts

CO2 utilization as a soft oxidant for the synthesis of styrene from ethylbenzene over Co3O4 supported on magnesium aluminate spinel: role of spinel activation temperature

Magnesium aluminate spinel (MgAl2O4) supported Co3O4 catalysts are synthesized and tested for the oxidative dehydrogenation (ODH) of ethylbenzene using CO2 as a soft oxidant. The effect of spinel calcination temperature on the catalytic performance has been systematically investigated. With an increase in the activation temperature from 600 to 900 °C, the active presence of a single-phase MgAl2O4 spinel is observed. A catalyst series consisting of MgAl2O4 spinel with varying Co loadings (10-20 wt%) were prepared and systematically distinguished by ICP, XRD, BET, TPR, NH3-TPD, UV-Vis DRS, FT-IR, XPS, SEM, and TEM. Among the tested cobalt catalysts, 15Co/800MA sample derived by calcination of MgAl2O4 support at 800 °C exhibits the most excellent catalytic performance with the maximum ethylbenzene conversion (≥ 82%). Also, high yields of styrene (≥ 81%) could be consistently achieved on the same active catalyst. Further, the catalyst exhibited almost stable activity during 20 h time-on-stream with a slow decrease in the ethylbenzene conversion from 82 to 59%. However, the selectivity of styrene (98%) stayed almost constant during the reaction. Activation of the MgAl2O4 spinel at 800 °C facilitates a dramatic chemical homogeneity for the alignment of Co3O4 nanoparticles on the surface of the active catalyst. Moreover, the isolated Co3O4 clusters have a strong chemical/electronic interaction with the Mg2+ and Al3+ ions on the support perform a crucial role to achieve the maximum catalytic activity.

Ni-promoted synthesis of graphitic carbon nanotubes from in situ produced graphitic carbon for dehydrogenation of ethylbenzene

Ni promoted the synthesis of graphitic carbon nanotubes from in situ produced graphitic carbon and exhibited excellent activity in dehydrogenation of ethylbenzene.

Activity studies of vanadium, iron, carbon and mixed oxides based catalysts for the oxidative dehydrogenation of ethylbenzene to styrene: a review

The activity of V, Fe and carbon based catalysts depends on V⁵⁺, Fe³⁺and active carbon sites. The mixed oxide catalysts show superior activity than individual oxides.