Microwave Induced Catalytic Synthesis Of Tungsten Carbide

Tungsten carbide is a material with unique physical and chemical properties. This material combines the properties of ionic crystals, covalent compounds and transition metals. It has been applied in various mechanical fields of high temperature resistance, abrasion resistance and corrosion resistance.

The traditional preparation process of tungsten carbide is inherited from metallurgical industry. It is a direct reaction of metal, metal hydride or metal oxide with a certain proportion of carbon in a reducing atmosphere. The reaction temperature is usually higher than 1500K. The products obtained have very low specific surface area and purity. These industrial materials are not suitable for use as catalysts or carriers. In order to adapt to the application of tungsten carbide in catalysis and adsorption, many methods for preparing tungsten carbide with high specific surface area have been developed in the smelting industry. For example, gas-phase reaction of volatile metal compounds, gas-phase reaction and solid-phase reaction, high temperature decomposition and liquid-phase reaction of metal compounds. It is found that the catalytic and adsorptive properties of tungsten carbide are closely related to its surface structure and composition, and the surface structure and composition of tungsten carbide are affected by the preparation process.

In recent years, some scholars have found that tungsten carbide can be rapidly heated to high temperature by microwave-induced catalysis, which has the characteristics of fast preparation speed and low energy consumption. Moreover, the reaction product is almost pure tungsten carbide catalyzed by metal powder materials. The main contents of this process are as follows:

Dissolve 1.0 g tungsten in 100 ml hydrogen peroxide, then add 1 g activated carbon powder, add 100 ml ethanol, put it into the ultrasonic cleaner for 30 minutes and disperse evenly, take out the stirring to the viscous slurry. Then the sticky slurry is put into the microwave oven, and the slurry is heated by alternating microwave operation for 5 seconds and stopping for 5 seconds to obtain the dry powder. Then the dry powder and 1 gram of iron powder are mechanically mixed evenly and put into the ceramic crucible. The microwave-resistant insulation material is wrapped around the ceramic crucible. Finally, the crucible was heated in a microwave oven for 20 minutes to obtain nanometer tungsten carbide particles.

The product was observed by X-ray and it was concluded that the reaction product was almost pure tungsten carbide catalyzed by metal powder materials, while the product without metal powder materials contained a large amount of tungsten oxide.

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