I. Zircon sand
Let's talk about zircon (zircon), which is the most important zirconium-bearing mineral. It is the most widely distributed, most abundant, and most abundant type of zirconium mineral. It is a kind of mineral mainly composed of zirconium silicate. . Zircon sand is the main raw material for the preparation of zirconium, hafnium and various zirconium products. It has the characteristics of high melting point, low thermal conductivity and small linear expansion coefficient. It is widely used in ceramics, metallurgy, casting and refractory materials industries. Its chemical composition: The theoretical composition of zircon sand: ZrO2: 67.1%, SiO2: 32.9%. Sometimes contains MnO, CaO, MgO, Fe2O3, Al2O3 mixed. Various colors, such as purple, brown, light yellow, light red, green, gray, colorless and other diamond, hardness: (Mohs') hardness of 7.5 ~ 8, specific gravity: 4.4 ~ 4.8, melting point: 2340 ~ 2550 °C, linear Thermal expansion coefficient: 5.0×10-6m/°C(200~1000°C), heat shock resistance, good stability. Conventionally, people usually divide zircon sand into 66, 65, 63, and 60 degrees according to the content of ZrO2 (useful component) in the zircon sand. The zircon sand is generally 80-120 mesh; the industry will fineness In the 325 mesh (about 40 microns) zircon sand is called zirconium powder, the fineness of more than 2000 is called zirconium silicate, worldwide distribution: zircon sand in various igneous rocks as an accessory mineral output, In the alkaline rocks and alkaline pegmatites can be integrated into the ore; zircon is also often enriched in the placer. From the perspective of geographical distribution of resources, it is mainly in the hands of Australia (44.6%), South Africa (25%), Ukraine, India, and Brazil. Five countries account for 86% of the world's zirconium resources, and the monopoly of resources is very obvious. China's zirconium reserves account for less than 1% of the world's zirconium reserves. With the further exploration of the exploration work, the production of zirconium in Mozambique, Indonesia, Madagascar, India and Vietnam showed an increasing trend and made a marginal contribution to the global supply of zirconium. At the company level, global zirconium supply is dominated by Australia's ILUKA, Rio Tinto and South Africa's Exxaro.
Zircon sand price:
Years |
ILUKA(Annual average tax price) |
2010 |
7000 |
2011 |
15000 |
2012 |
14000 |
2013 |
9000 |
2014 |
8000 |
2015 |
8000 |
2016 |
7450 |
2017 |
?????? |
Zircon sand is the first raw material for the production of zirconium products, which can be used to produce zirconium silicate and zirconyl oxychloride. Zirconium oxychloride is a zirconium product produced from zirconium carbonate, zirconium sulfate, zirconium dioxide, zirconium oxide composite, zirconium metal, etc. The main raw material, composite zirconia, is the main raw material for the production of zirconia structural ceramics. Its upstream and downstream relationships are as follows:
Zircon sand industrial use is as follows:
No. |
Industrial USES |
Accounting |
1 |
ceramics |
56.11% |
2 |
Zirconia and zirconium chemicals. |
17.78% |
3 |
Refractory industry |
10.56% |
4 |
Foundry industry |
8.89% |
5 |
TV glass |
3.89% |
6 |
Other industries |
2.78% |
Zirconium silicate.
Zirconium silicate is a fine powder produced by the process of wet ball milling and dry process. Major in ceramic body when brightener and opacifying agent used, opacifying agent used in the us, for example, ZrO2, ZrSiO4, SeO2, TiO2 and ZnO ZrSiO4 is the only natural crystalline state, others are the chemical reaction of chemical products. Zirconium in rich value of 0.2% in the earth's crust, abundant reserves, and natural mineral are mostly in the form of zircon sand, research so far, there is no natural crystal mineral was applied to the opacifying agent, this is, of course, by its own structure reasons. Zirconium silicate in the glaze ceramic billet, therefore, have the following main functions: (1) opacifying (dark), whitening, (2) to strengthen the body strength and (3) strengthen the resistance to hydrolysis, (4) strengthen the hardness and wear resistance. ZrSiO4 in ceramic glaze unsubstitutable role in the conclusion, until today's practice has proved that find a substitute for zirconium silicate is still a very difficult job. Zirconium silicate market has many kinds, you buy the zirconium silicate belongs to what content. Based on 66 levels, with senior ATO wet sand ball mill of zirconium silicate as the standard, it is divided into: SiO2 < 32%, Al2O3 < 1%, ZrO2 > 65.3%, Fe2O3 < 0.1%, TiO2 < 0.1%, impurity content sum not more than 1%. How can you get the full analysis of zirconium silicate? What method can get the real content of zirconium silicate, we compared the current chemical analysis method of zirconium silicate, chemical analysis method for determination of zirconium (hafnium and zirconium XRF measuring the amount of the difference between the amount of (hafnium)
|
Chemical analysis of zirconium (hafnium) |
Determination of Zirconium by X-ray Fluorescence Spectrometry |
Theoretical basis |
GB/T 4984-2007
A) bitter almond acid weight method.
B) EDTA complex titration.
|
X-ray fluorescence analysis, based on the characteristic lines of X-ray reflectance, refraction, and scattering of electrons in outer layers of zirconium (hafnium) nuclei, in comparison with the intensity of the curve of the reference material |
Measurement operation |
Sample pretreatment: the process is completely consistent, including.
Crushing, grinding, drying and burning.
|
Sample pretreatment: the process is completely consistent, including.
Crushing, grinding, drying and burning.
|
Melting sample: a) sulfuric acid + hydrofluoric acid melting method.
B) mixture of boric acid + sodium carbonate.
|
Melting sample: borate glass is made of borate glass. |
Solution separation washing: a and b have complex dissolution, separation, washing and precipitation processes. |
Dissolving and separating washing: none |
Analytical determination process:
a) The washed precipitate needs to be weighed and weighed in a high-temperature furnace
b) Need complex titration and subtract impurities
|
Analysis and determination process:
Put in the fluorescence analyzer, and start the program to measure the results of 7~8 minutes automatically (all results)
|
Advantages Disadvantages |
Advantages: national standard method;
Disadvantages: long detection time, many factors, large fluctuation, and high level of responsibility and technical level of the analysis and detection personnel.
|
Advantages: Short sample preparation time, rapid detection, stable test results.
Disadvantages: dependence on the standard material, the instrument is more expensive
|
;
The content of SiO2 and Al2O3 can be seen in the grinding process of zirconium silicate. For more details, please pay attention to the WeChat public account of Zibo Bosite Technology Service Co., Ltd. The content of ZrO2, Fe2O3, TiO2 can be seen as the quality of zircon sand produced by zirconium silicate milling. For more details, you can find out whether the zirconium silicate you bought is adulterated. So what is everyone's so-called brightener? Please pay attention to Zibo Bosite Technology Services Co., Ltd. WeChat public number.
Three, zircon powder
Usually zirconium powder refers to zircon sand milled to 325 mesh after a certain process. It is used in the ceramic frit and refractory industry. Its ceramic frit is mainly used in zirconium white frit and inkjet frit, but in zirconium. The mechanism of the white frit and the inkjet frit differs. The difference in zirconium powder used by everyone is also great. Zirconium white frit requires not only enough zirconium content, but also iron, titanium and aluminum content. The content of iron and titanium is high, the glaze is easy to yellow, the aluminum content is high, and the glaze opacity is easily deteriorated. The requirements for iron and titanium content of the frit are low, which is mainly used to help the color development. Therefore, many grades of zirconium powders have appeared on the market. The current detection of zirconium in Shandong is mainly based on EDTA complexometric titration. The zirconium content was not tested for each batch, resulting in a rather unstable product batch quality.
In the market, the amount of zirconium sand was analyzed by chemical analysis.
|
MB Advanced |
MB standard |
South Africa |
Indonesia |
Mozambique |
Vietnam |
Hainan |
ZrO2(%) |
65.95 |
65.71 |
|
66.54 |
|
|
66.51 |
SiO2(%) |
33.37 |
33.41 |
|
33.10 |
|
|
32.47 |
Al2O3(%) |
0.52 |
0.63 |
|
0.23 |
|
|
0.06 |
Fe2O3(%) |
0.03 |
0.05 |
|
0.03 |
|
|
0.21 |
K2O(%) |
0.05 |
0.05 |
|
0.05 |
|
|
0.02 |
TiO2(%) |
0.05 |
0.12 |
|
0.01 |
|
|
0.28 |
PbO(%) |
0.02 |
0.02 |
|
0.03 |
|
|
0.03 |
烧失(900℃) |
0.05~0.3 |
0.05~0.3 |
|
0.05~0.3 |
|
|
0.05~0.9
|