Rhenium, one of the most recent natural elements, is one of the high melting point metals. Rhenium was named after the Rhine river because its discoverer was a German chemist. Rhenium is found in molybdenite, rare-earth ore and niobium tantalum ore, and its content is very low. So far only two independent rhenium minerals, ReS2 and CuReS4, have been found.
The main raw material for rhenium production is the by-product of molybdenum smelting process. The data show that rhenium is mostly associated with molybdenum, copper, zinc, lead and other minerals, and is difficult to be used alone.
Rhenium, at about 1×10^-7% in the earth's crust, is smaller than all rare-earth elements and harder to get than diamonds. According to the US Geological Survey, the world's proven reserves of rhenium are only about 2,500 tonnes, and the price of rhenium is similar to that of platinum. A gram of rhenium costs about rmb200 or RMB300.
Because of the scarcity of resources and the high price, there has been little research on rhenium for a long time. After 1950, Rhenium began to be used in modern technology and its production developed day by day. Rhenium was extracted from roasting dust of molybdenum concentrate in 1960 in China.
Because rhenium is widely used in jet and rocket engines, about 80 per cent of the world's rhenium is used in aircraft engines, making it strategically important. It is said that whether the efficient development and utilization of rhenium can be realized is the breakthrough for the aviation industry to enter a new era.
For a long time, aero-engine has been a short board in our aviation industry. Until now, some of China's military aircraft still use foreign engines, and in the commercial aviation sector, the Engines used in the C-919 jumbo jet are produced by a JOINT venture between the United States and France.
