博文

目前显示的是 十一月, 2017的博文

Ten Factors Affecting the Ammonium Paratungstate Crystallization(2)

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Ammonium paratungstate (APT) is an important tungsten intermediate product, not only in the purity and process requirements, as well as crystal grain size and crystal distribution requirements. Seemingly negligible some of the objective factors often play a key role in the final product often For these reasons the difference between the least, lost thousands of miles. 6. The impurities in the solution: As the solution P, As, Mo, Si and other impurities easily adsorbed on the crystal growth of the active point, hinder the crystal growth, but also makes the ammonium paratungstate grain thinning, make the quality of deterioration, and easy to enter the product during the evaporation crystallization process, affecting product quality, and even lead to product failure, so in the crystallization process, should take the control of crystallization rate, improve the concentration of NH 4 Cl in ammonium tungstate solution, stirring and washing agents and other methods, to achieve th

Ten Factors Affecting the Ammonium Paratungstate Crystallization(1)

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Ammonium paratungstate (APT) is an important tungsten intermediate product, mainly white crystals, there are two kinds of flakes or needle-like, used in the manufacture of tungsten trioxide or blue tungsten oxide tungsten powder. The quality of tungsten products depends largely on the chemical purity of APT, particle size and particle size distribution. APT quality standards from the domestic manufacturers, the process and chemical purity are almost the same, but the production of APT products vary widely, this is because APT is a system engineering, not only the purity and process requirements, as well as crystal grain size and crystal distribution requirements, seemingly insignificant on some of the objective factors often play a key role in the final product is often because of these reasons the difference between the least, lost thousands of miles. There are lots of influence factors of ammonium tungstate, mainly include: the temperature of the solution, the degree

Ammonium Paratungstate Crystallization Mother Liquor Treatment--Conversion Method

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From dressing industrial progress of history suggests that mineral processing reagents application significance is self-evident.  Since its discovery in 1924 xanthate has the function of collecting sulfide ore, the development of the flotation industry started by leaps and bounds, the inundated mineral processing reagents has been invented and created with a steady stream. The crystallization crystallization method and the neutralization method produce the crystallization mother liquor in the preparation of APT. These mother liquor contain not only impurities but also some WO 3 . In order to improve the total recovery of tungsten, the mother liquor is often recovered once again in the industry treatment, as to which method should be based on the previous process and the composition of the mother liquor to use, usually available alternative methods are conversion method, solution extraction and ion exchange method. Conversion method is commonly used in the crys

Wolframite and Scheelite Mixed Tungsten Ore Flotation (2)

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Wolframite and scheelite mixed tungsten ore flotation is a worldwide difficult problem, because of the black and white tungsten composition structure is very different, conventional flotation method at room temperature and heating method is not ideal. Would there have a more effective way to realize whether black and white tungsten mixed flotation? Chairman MAO once said: “There is a way, it just hasn’t been found.” He also said: “Paths are made by men.” And actually it does. After many years of industry practice, our country's scholars found that the focus on black and white tungsten study is mixed flotation collector, the flotation is strong while the collector is strong, scholars use the collector as the breakthrough point, make many light avenues. In 70s and 90s, Chinese scholars use 731 + 733 combination of black and white mixed tungsten ore flotation collector, 731 and 733 to mix ratio of 10:1, the collector has the advantage of source is easy to obtain, the dis

Wolframite and Scheelite Mixed Tungsten Ore Flotation (1)

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Wolframite and scheelite are different with the same name, there are all “w” but their body structure are not the same, so their beneficiation method is different, black tungsten gravity commonly used the separation method, scheelite commonly used flotation process. After years of development, our country each has a solid industrial foundation of beneficiation technology in wolframite and scheelite tungsten ore flotation. From a single scheelite recovery of scheelite in bed or recovery of wolframite from single black tungsten deposit is relatively easy. But why there is a certain type of skarn deposits made mistake like, they try to make the black and white tungsten together under the same roof, so the deposit is called "black and white mixed tungsten deposit. Mixed black and white tungsten ore flotation is a worldwide difficult problem, in this type of ore deposits, the black and white tungsten are in fine grained disseminated separately symbiosis in the strata, alth

Combination Collector Mechanism--Chelating Effect

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In the flotation system, two or more collectors are used in combination, and by combining the collector and producing synergistic effects, such tungsten ore flotation collector is known as combination collector in practice. It has been proved that many combination collector has better and more effective flotation results than the use of a single collector, and there are divergent views on the causes. For the study of the mechanism of the combination collector, there are scholars think that the combination collector also has a significant chelating effect, it refers to the combination collector and mineral surface of the metal between the combination collector metal's special affinity caused by the real chemical reaction. The result of this reaction is the formation of insoluble, stable metal chelate.  The scholars of South China University used the quantum chemistry ab initio algorithm to calculate the molecular model of benzohydroxamic acid and benzyloxamic acid. T