The performance of pretreated tungsten carbide powder

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Due to the decomposition of carbon, pure tungsten carbide powder is easy to pollute by oxygen under normal temperature. In order to improve the performance, tungsten carbide powder can be pretreated. After pretreatment, the performance of tungsten carbide powder will be very active; beside, its catalytic performance will increase 10 times.

pretreated tungsten carbide powder

In the pretreatment of tungsten carbide metal powder, tungsten carbide powder is reduced firstly under 1073K and 30ml/min hydrogen in 5 hours; afterwards, the tungsten carbide powder will be measured by TPR method and will be compared with the powders before reduction; the results show that N2 absorption specific area is not changed obviously, while the chemical absorption quantity of hydrogen and carbonic oxide increases from 0.1-0.5μmol/g to about 100μmol/g, which can remove the excess carbon on the tungsten carbide surface. After replacing the tungsten carbide powder that is pretreated in the air about one year and further checking the performance of tungsten carbide powder, results show that the composition of tungsten carbide powder is not changed greatly, the oxygen content is kept in a reasonable range, carbon in the tungsten carbide powder is very active, the catalytic activity of tungsten carbide powder increases 10 times and the isomerization selectivity also increases in some degree.