Ammonium Metatungstate (AMT) Preparing Spherical Tungsten Carbide Powder

spherical tungsten carbide powder imagespherical tungsten carbide powder imagespherical tungsten carbide powder imageBecause of spherical tungsten carbide powder (WC) has the properties of high hardness, wear resisting and chemical property and acid and alkali resistant, it has widely potential application value in the fields of fuel cell anode, cathode catalyst material, gas sensor, petroleum catalyst, photocatalyst material. 
 
Tungsten carbide powder prepared by the existing method which is directly roasting tungsten powder and carbon under the high temperature, has the irregular shapes, and thus hard to meet special requirements in some fields.
 
Studies have found a new method for synthesizing spherical tungsten carbide powder, which is taking glucose solution as carbon source template to the prepare spherical frame, then using soluble tungstate - ammonium metatungstate as tungsten source, then to get spherical tungsten carbide powder with through certain technical conditions and molar ratio of raw materials.
 
Instances are as follows: 
1. Mix ammonium metatungstate and glucose solution with the mass concentration of 7% according to the mole ratio of 1:30, then roasting it in a high pressure reaction kettle at 200°C for 24 hours, dry it under the condition of the temperature of 90°C after filtered; roast the reactant under 900°C in a fourteen tube furnace with ammonia gas for 9 hours to prepare restore former polymers, and finally roast in a steel furnace under 1200°C for 3 ~ 5 hours to carry out a carbonation reaction to finally get spherical tungsten carbide powder. 
 
2. Mix ammonium metatungstate and glucose solution with the mass concentration of 4% according to the mole ratio of 1:15, and place the mixture in a high pressure reaction kettle under 200°C for 24 hours; after filtering, the mixture is dried under the condition of 70°C, and then, we will roast the reactant in a fourteen tube furnace under 700°C with ammonia gas for 7 hours to get restore former polymers, then calcine it at 900°C in a steel furnace for 2 hours to carry out a carbonization, then to get spherical tungsten carbide powder. 
 
This method has the advantages of simple synthesis process and easy to realize industrial production, at the same time, the resulting spherical tungsten carbide powder has excellent properties of high purity, hardness, wear resistance and chemical stability, as well as acid and alkali resistance and so on.

 

 

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