Surface Morphology during Tungsten Electrode Operation

After 5 seconds arcing, observed tungsten electrode surface morphology found, the tip of electrode has many projections. And this is mainly because the tip affected by current and high-frequency the surface rudimental oxygen will react with tungsten to generate volatile tungsten oxide under heat effect and since arcing was carried out in an argon atmosphere, so the tungsten oxide which produced at the tip will take away by argon gas, leaving relatively clean tungsten grain. However, with arcing time increase, the tungsten which in the middle part of the tip tungsten will react with residual oxygen to produce tungsten oxide. And this tungsten oxide will bring to the top of tip which has higher temperature by argon flow. During the process, tungsten oxide decomposition occurs to form metal tungsten. Besides, tungsten deposition led to form the projection on the tip. However, this structure is prone to produce high frequency discharge and plasma. Not only tungsten and oxygen can react to produce gaseous tungsten oxide, but low-melting substance such as rare earth nitrate in tungsten electrode during arcing process will have diffusion, migration, volatilization and deposition, which is conducive to high-frequency arc starting and stable arcing.
 
After one minute arcing, observed morphology found due to longer arcing electrode material has undergone obvious recrystallization. The tungsten film which deposited at the before affected by heat will along the grain to growth and only new deposited tungsten film shows amorphous membranous tissue. In the one minute arcing, the tungsten electrode surface covered with typically equiaxed recrystallized structure tungsten film.
 
After 5 minutes arcing, the root of tip, due to the lower temperature so there is showing processing state fibrous tissue. In addition, compared the electrode tip morphology after five minutes arcing and one minute arcing found there is little change in appearance, indicating that arcing after one minute the electrode enters a relatively stable state and can stable work .
tungsten electrode morphology

5 Companies Fined More Than 3.5 Million Yuan, WO3 Desulfurization Catalyst Reduces Acid Rain

Recently, media reports said Development and Reform Commission (NDRC) of Yunnan Province have maken out the illegal administrative penalties of 5 electric powder enterprises for confiscating their illegal incomes, the total illegal incomes of more than 3.50 million. It is reported that the major reason of the five electric powder enterprises to be punished including that generated and outwardly supplied electricity during the outage of desulphurization facilities, related emission concentration index hourly average exceeds the limit but still requires enforcement of environmental price, and so on. In this regard, I express my deep sorrow, as well as have no more agree for the treatment of NDRC, how dare they generated power under the outage of desulphurization facilities? Today, the whole world is doing environmental protection work, and you commit a crime in spite of a law-enforcement campaign, anyone without you not to be punished?

tungsten trioxide and desulfurization catalyst
 
The pollution of sulfur dioxide has exceed the smoke pollution and become the first atmospheric pollutants, with the world’ industrialization continues to deepen. Flue gas desulfurization (FGD) is currently the world's only desulfurization method of large-scale commercial applications, and also the most effective and main technical means to control acid rain and sulfur dioxide pollution. Desulfurization tower is commonly used in desulfurization facilities, and the desulfurization catalyst is a core technology used in desulfurization project, the surface of WOdesulfurization catalyst has tension which can reduce the surface tension of limestone slurry and the critical nucleus radius, thereby strengthening the bisulfite oxidation precipitation of gypsum, to achieve the goal of sulfur dioxide emission reduction.
 
Tungsten trioxide (WO3) is an important intermediate product from tungsten concentrates to pure tungsten; the large amounts of WOare used in the production of pure tungsten, tungsten carbide, etc; In addition, as WO3has catalytic property, it can either as the main catalyst (photocatalyst), and also can be used for preparing denitrification, desulfurization catalyst. In the desulfurization catalyst, WOas a main active material which uniformly loading on the carrier, serve to reduce the desulfurization reaction activation energy, and also play the roles of anti vulcanization, anti-sintering of carrier, thereby enhance the desulfurization efficiency and achieve the goal of emission reduction.

 

Natural Gas May Be Chinese First Choice of Energy Transformation, WO3 Denitration Catalyst Controls NOx

On the activity of "G20 Gas Day" which held on June 29th, the experts pointed out that, compared to other fossil fuels, natural gas has the advantages of low pollution, low emission; while the utilization of natural gas is relatively flexible, and can compensate for the disadvantages of the unstable state of renewable energy, therefore, in the process of Chinese restructuring and optimization of energy, natural gas will be the first choice of transitional energy.
 
However, while natural gas is considered as a clean fuel, it does not mean that it will not pollute the environment, at the same time, it also increases the total emissions of nitrogen oxides; especially within the family use, the flue gas directly emissions have brought some pressure to the environment protection. Combustion products of natural gas are NOx (the complete combustion product is: nitrogen dioxide; incomplete combustion product is: NO), water, carbon dioxide (incomplete combustion product is: carbon monoxide) and so on, or may contain sulfur dioxide and other toxic substances, which mainly depends on the composition of natural gas. Therefore, the denitration project of combustion exhaust gas of natural gas is very necessary.

denitration catalyst and natural gas pipeline
 
TiO2-WO3-V2O5 ceramic honeycomb denitration catalyst is a typical SCR catalyst, is the core of the SCR denitration system in industrial, its efficient and reliable operation determines the denitration efficiency. In the component of WO3denitration catalyst, the titanium dioxide plays the carrier role for loading active substance, which accounting for about 85% of the total catalyst mass; vanadium pentoxide is the main active substance, accounting for about 7%; WO3as catalyst promoter, takes an amount of about 10%, which primarily plays the role of anti-sulfide, poisoning resistance, and while increasing the temperature adaptability and thermal stability, thus to avoid the occurrence of the carrier being sintered and deactivation under a high temperatures in a short time.
 
Further Reading:
Natural gas means any gas naturally existing in nature, including the atmosphere, hydrosphere gas and lithosphere which is formed by natural processes (including oil, gas field, mud volcanoes, coal bed methane and biogenesis and other gases). The natural gas which people usually says is the narrow definition from the energy point of view, it refers to the mixture gas which natural reserves in the formation of a of hydrocarbon and non-hydrocarbon, and mostly hidden in underground porous rock formations, and considered as the high-quality fuels and chemical raw materials.

 

Tungsten Market: ‘Winter is Coming’

With the finish of hot American TV Series <Game of Thrones> Season 6, ‘the winter is really coming’ after all these 6 seasons. All of us have an expectation for who will finally reign the seven kingdoms and let’s wait and see what will happen in Season 7 in 2017.

Coincidentally, tungsten market has entered the traditional slack season in July and August with the break of European & American countries. That’s why we say that ‘winter is coming’.

National tungsten market has been settled in an awkard situation for a long time. Not only for the decreased demand, but also the uncertainty sentiment of market participants. The summer break of European and American countries will absolutely have negative influence on the tungsten market. However, price of tungsten shall never fall to such a low level. After all, the value of tungsten is far from this. In October, 2015, national tungsten products price slacked to the bottom since 2004. All the special factors brew and cause the result. People would reckon that will tungsten price falls again to the bottom of last year?

Tungsten Concentrate Price Trend

Since May, 2016, price of APT falls down for 30 thousand RMB/ton since it increases about 130 thousand RMB/ton, which has been just a month. It that were not enough, tungsten slack season is coming which results in delay of recovery. Price of APT has been below 100 thousand RMB/ton, will it be below 90 thousand/ton? Since the winter is already coming, we should focus on how to stay warm and struggle through this period instead of talking about the temperature.

APT Price Trend

Tungsten powder purchase amount has shown the backdrop, as well as tungsten carbide products. Although the market is depressed, the falling and increasing of price has its own sequence. All of us should have a rational reflection on this serious situation. The falling of price is not necessarily a good thing, it would be best chance for regular customers to purchase some stock. There may be downtick anytime due to special reasons of funds, stock, product and customer. Manufacturer should have the theory of always keep the quality of products. Customer service and comprehensive strength are the key points in such depressed market.

Let’s keep enthusiastic attitude to stay optimistic for the ‘winter’ of tungsten market in such hot hot summer.

Tungsten Trioxide Applicable In New Water Electrolyzing Catalyst

Recently, the Chinese Academy of Physical and Chemical Research Institute has successfully synthesized a highly efficient water electrolyzing catalyst to achieve high efficiency at a low voltage of activating water molecules, and offered the potential for solving the future energy crisis. Hydrogen is considered as the best source of energy, unlike the other new energy sources, like solar, nuclear, ocean, biomass and geothermal energy and so on, it belongs to the energy of energetic body which is available direct combustion. Among the hydrogen production technologies, the way of solar water photolysis or photo-assisted electrolysis of water is one of the most promising and efficient pathway, which is depending on the semiconductor electrode, and moreover, the water electrolyzing catalyst can greatly improve the efficiency of water electrolysis hydrogen.

tungsten trioxide and water
 
Zhang Rui, one of the researchers led his team carried out a in-depth study on the nanostructure of "Hydrotalcite (LDH)" clay mineral, through precise regulation of the hydrotalcite precursor morphology, and synthesized the ultra-thin and ultra-small heterogeneous nanostructures of NiO / TiO2by calcination under a high temperature. Studies have shown that this structure exhibited a superior catalytic performance in terms of electro-catalytic decomposition for generating hydrogen and oxygen. At the same time, studies have shown that the catalyst synthesis method is simple, and used the abundant nature of non-precious metal as the raw material, the obtained product of ultra-thin and ultra-small material of NiO / TiO2has the application value in the respects of electro-catalytic decomposition of water, capacitors ect.; also, it is applicable to other metal oxides (such as tungsten trioxide) to prepare the nanosheets electro-catalyst.
 
Tungsten (W) , an element of the transition metal in ⅥB family; tungsten trioxide is an important oxide in the tungsten metallurgical industry, which has semiconductor property; because of its catalytic property, it is commonly used in the preparation of the denitration, hydrodesulfurization, photocatalyst and other catalysts. Study on catalyst of titanium dioxide has been more than 40 years, while the international research on tungsten trioxide applied on the photocatalyst, water electrolysis catalyst is just in the early phase, we believe that in the near future, researchers will slowly open the mystery of tungsten trioxide in this regard applications.

 

 

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