The role of carburization temperature on the molybdenum carbide surface and their catalytic activity
محورهای موضوعی : Iranian Journal of Catalysis
1 - Department of Chemical Sciences, Faculty of Science, Adekunle Ajasin University, Akungba Akoko, Nigeria.
کلید واژه: reduction, Oxidation, Activity, Hydroisomerization, Carburisation temperature,
چکیده مقاله :
The surfaces of molybdenum carbide were varied by changing the carburization temperature between 823 and 1123 K. The surfaces of the catalytic material were investigated using in-situ temperature program carburization followed by temperature program reduction and oxidation. In-situ temperature program oxidation (TPO) showed the surfaces of the catalysts contain a similar amount of carbonaceous deposit, while temperature program reduction (TPR) showed their ability to consume hydrogen in different amounts. The result shows the surface of the carbide at 823 K contained oxygen, while those carburized at higher temperature (≥ 923 K) were pure carbide. The catalysts tested for hydroisomerization of n-heptane and the catalyst with oxycarbide surface showed higher activity and iso-heptane selectivity. Hence, carburization temperature plays a crucial role in the formation of an active catalyst.
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