The present invention provides a method for producing a rare earth-doped tungsten oxide powder, a refractory metal belonging to the technical field of rare earth materials.

Process: First, low-temperature combustion synthesis method using rare earth oxides (Sc2O3, Y2O3, La2O3, CeO2, ZrO2, Gd2O3 and Eu2O3 one or several) and tungsten oxide precursor powder uniformly mixed, and then the precursor powder was calcined in a muffle furnace, and finally the two-step reduction in a hydrogen or cracked ammonia atmosphere. Easily reducible tungsten oxide is reduced to tungsten powder, but can not restore rare earth oxide particles retained, resulting in rare earth oxide doped tungsten powder. Oxides of rare earth doped rare earth oxide content of the tungsten powder is 0.05 ~ 35wt%;.

Advantages of the present invention is that the target element, and an organic carbon source to form a highly dispersed system of fine and uniform particle size of the resulting oxide. Due to the low cost of raw materials, reaction speed, low power consumption, simple process, and therefore more suitable for industrial production.




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The invention belongs to the field of environmental protection, and in particular relates to a synthetic method of a double-component composite oxide containing TiO2 and WO3.

The synthetic method comprises steps of: taking an appropriate amount of metatitanic acid solid, and utilizing an intensive mixer half-dry mixing method to break the metatitanic acid solid into small particles; at the same time, dissolving ammonium paratungstate in an ethanol amine or hydrogen peroxide-nitric acid solution under the heating condition; then directly adding the ammonium paratungstate solution and a surfactant into the small metatitanic acid particles, and utilizing ammonia water to regulate the pH value of a material; and adopting an intensive mixer to mix and drain the material for a while, then directly calcining the material in a rotary kiln for 3-8 hours, milling a calcined product through utilizing a ball mill or a superfine mill, and thus synthesizing a TiO2-WO3 composite oxide powder. The crystal form of the obtained TiO2-WO3 composite oxide is in an anatase structure, the TiO2-WO3 composite oxide particles are uniform, and the specific surface area of the TiO2-WO3 composite oxide is suitable (80-150m<2>/g).

According to the method, a half-dry mixed head product can be directly calcinated; the method has the characteristics of controllable product ingredients, excellent performance, simple operation process and the like, and can be easily used for large-scale industrial production; and moreover, a pollutant-ammonia is exhausted in a gas phase and easily controlled.


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The invention discloses a method for recycling tungsten and ammonia in one step from an ammonium paratungstate crystallization mother solution smelt through tungsten.

After the ammonium paratungstate (APT) is subjected to evaporative crystallization, a mother solution is pumped into a reaction kettle for stripping treatment, calcium oxide with content above 90% or calcium hydroxide with content above 95% are added into the mother solution, a stripping process which is commonly used in the crystallization mother solution in the APT preparation process is utilized to recycle the ammonia, the reaction temperature is in a range from 25 DEG C to 90 DEG C, when the ammonia is subjected to gas-liquid separation through condensation concentration, the ammonia is sprayed with a hydrochloric acid to prepare ammonium chloride to return to a main process to prepare an analytical solution, white tungsten slag returns to a pressure boiling process, when a potential of hydrogen (pH) value of a reaction system is maintained in a range from 9 to 11 and concentration of ammonia nitrogen in water is reduced to about 30mg/L, the reaction is finished, and a waste liquid free of the ammonia nitrogen is subjected to a mixing treatment with an ion exchange post-liquid which is generated in the main process working procedure.

The method has the advantages that the process procedures are greatly simplified, the tungsten deposition rate is high, the process is simple, the operation is easy, and the treating cost is slightly low.


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Disclosed is a method for producing high compact strength tungsten powder.

Ammonium paratungstate and purple tungsten oxide serving as raw materials are uniformly mixed according to a certain proportion, mixed powder is placed into a hydrogen reduction furnace, the thickness of a material bed is 5-25mm, the mixed powder is heated up to 700-1100 DEG C at the speed of 5-20 DEG C/min and is directly reduced with hydrogen, holding time is 1-5 hours, the dew-point temperature of the hydrogen ranges from -40 DEG C to -65 DEG C, and finally, reduced powder is sieved to obtain the high compact strength tungsten powder. The tungsten powder produced by the method can be pressed into high-strength compact without adding any forming agents, the compact strength of the tungsten powder is as high as 3.0-5.0MPa, and a tungsten product made of the tungsten powder has the advantages of high density, fine high-temperature resistance, stable quality and the like.

The preparation method and preparation steps are quite simple, and technological parameters of the preparation process are easily controlled.


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