Discovery of strontium and its scientific application
Strontium discovery process
Around the year 1787, at some European exhibitions, an ore was taken from a lead deposit in Strontian, Scotland, England. Some chemists think it is a fluorite. In 1790, Crawford in Scotland was the first time to identify the existence of strontium carbonate; 1792, the British chemist, doctor Hope confirmed that the strontium-containing ore, it is clear carbonate , But different from barium carbonate, followed by the separation of barium, strontium, calcium compounds. From its origin Strontian named it strontia (strontium soil). 1789 Lavoisier published elements of the table there is no time to discharge into the strontium soil. And David caught up with him in 1808, using electrolysis: mercury cathodic electrolysis of strontium hydroxide, strontium carbonate separated from the pure metal strontium, and named strontium, element symbols with Sr.
The Use of Strontium
Strontium is mainly used in the manufacture of alloys, photoelectric tubes, and analytical chemistry, fireworks and so on. The mass of 90 strontium is a radioactive isotope, can be used as β-ray radiation source, half-life of 25 years. Strontium is widely used in various fields such as electron, chemical, metallurgy, military, light industry, medicine and optics because of its strong absorption of X-ray radiation and unique physical and chemical properties. Barium, strontium, calcium and magnesium are alkaline earth metals, but also more elements in the crust. However, barium and strontium in the crust in the content and calcium, magnesium compared to, or less. Coupled with their practical application of compounds less than calcium and magnesium compounds widely. Their compounds are later known as calcium and magnesium compounds, except that Davy separates barium and strontium from calcium and magnesium electrolytically from the compound at the same time.
Strontium applications
With the continuous development of the world industry, the use of Strontium also will gradually expand and change. From the end of the 19th century to the beginning of this century, strontium hydroxide was used in the sugar industry to purify sugar beet syrup. During the two world wars, strontium compounds were widely used in the production of pyrotechnics and signal beacons. In the 1920s and 1930s, The purity of up to 99.99%; the late 60s, strontium carbonate is widely used as a magnetic material; titanic acid (titanic acid) to remove sulfur, phosphorus and other harmful impurities; 50 years, in the production of zinc, Strontium used in computer memory, strontium chloride used as rocket fuel; strontium carbonate shielding in 1968 found that the function of X-ray, and its application to the color television screen glass, is a substantial increase in demand; strontium in other areas But also continue to expand its scope of application. Since then, strontium carbonate and other strontium compounds (strontium salt) as an important raw material of inorganic salts, has been widespread concern and attention.
According to the steady growth of Strontium demand in the world and China’s abundant strontium resources and good prospects for strontium ore prospecting, strontium ore resources in addition to meet the needs of China’s national economic development process itself, but also the development of strontium ore resources and a variety of products Export-oriented mining economy, to participate in international competition. Therefore, the strontium ore resources is not only the world’s important strategic mineral resources, but also in China’s national economy in the position and role, will also be increasing, becoming increasingly important.
In the medical application: Strontium is a trace element in the human body, the vast majority of strontium are stored in bone tissue. It can regulate the structure of bone tissue, improve bone strength, promote bone cell physiological activity. Strontium salt can inhibit the activity of osteoclasts, promote the activity of osteoblasts and promote the deposition of bone salt; and it can be used in combination with hydroxyapatite and tricalcium phosphate, etc .. Strontium salts can inhibit bone resorption and increase bone formation. After the compound, the mechanical strength, solubility and induced osteogenic ability and other characteristics were improved; strontium salt oral treatment of osteoporosis. CONCLUSION: Strontium has an irreplaceable physiological role in the growth and differentiation of bone cells and bone matrix absorption and deposition. It is necessary to pay more attention to the research and development of bone tissue engineering.
Strontium species
Strontium is widely distributed in the nature of trace elements. Strontium in the fifth cycle of the periodic table of the second group, is one of the alkaline earth metal elements. So far, the world has been found about 46 kinds of strontium minerals.
1, Celestite (Celestite) Celestite is often thick plate or columnar, aggregates were granular, occasionally fibrous, nodular. Lapis lazuli pure crystal, colorless and transparent, usually white, light blue, glass luster, cleavage face pearl color change.
2, Strontium carbonate ore (Strontianite), often with calcium. Strontium carbonate is often associated with celestite ore, usually distributed in the surface of the celestite ore body leaching zone, only in a specific geological and geomorphic conditions of celestite, in the diving surface and above part of the formation of possible Industrial value of strontium carbonate ore deposits or deposits.
3, Strontium-rich aragonite (Strontianiferous).
4, parathionite (Svanbergite), is a tripartite system, mineral granular, plate, columnar, diamond hexahedron, with a ring structure of the rounded beans granular and fan-shaped debris.
- Arsenogoyazite (Arsenogoyazite) was first discovered in Germany (Walenta et al., 1984) as a new mineral.
6, potassium Strontium alum (Kalistrontite), first found in the former Soviet Union somewhere in the lower part of the salt (Bopohba, 1962). Is a tripartite system, generally spindle-shaped, spindle-shaped, cylindrical self-crystal, particle size of 0.1 ~ 2mm, scattered distribution in the rock. Mineral was brown, gray, white, brittle, D = 3.34.
- Strontium woodhouseite is an intermediate transitional mineral of the Svanbergite and the calcium-aluminosilicate family (Qin et al., 1984). Mineral is a tripartite system, white, under the microscope was colorless transparent crystallite aggregates.
8, calcium carbon Strontium cerium ore (Calcianancylite), is a carbon strontium ore (Ancylite) of a calcium subspecies higher. Mineral colorless or strontium ferrite powder pale yellow, he shaped or semi-self-fine crystal combination. Orthorhombic system.
9, Strontium cerium sodium (Strontium Carbocernaite), first discovered in 1961 in the former Soviet Union Kola peninsula. Mineral is orthorhombic, white coarse grain, the maximum particle size of 2 cm. (Samples mixed with a small amount of calcite and 2% to 3% chlorite, iron oxide and other minerals). However, as the industrial extraction of Strontium is the most important mineral celestite, only a small number of deposits using strontium carbonate ore. Strontium parathion and strontium containing underground brine, etc., as a potential comprehensive utilization of the object, with a certain industrial significance.