Rhenium(VII) oxide and perrhenic acid readily dissolve in water; they are leached from flue dusts and gasses and extracted by precipitating with potassium or ammonium chloride as the perrhenate salts, and purified by recrystallization.
Recycling of used Pt-Re catalyst and special alloys allow the recovery of another 10 tons per year.
It also has one of the highest boiling points of all elements.
It is also one of the densest, exceeded only by platinum, iridium and osmium.
Prices for the metal rose rapidly in early 2008, from 00–00 per kg in 2003–2006 to over ,000 in February 2008.
Second-generation alloys contain 3%; these alloys were used in the engines for the F-15 and F-16, whereas the newer single-crystal third-generation alloys contain 6% of rhenium; they are used in the F-22 and F-35 engines.
In 1908, Japanese chemist Masataka Ogawa announced that he had discovered the 43rd element and named it nipponium (Np) after Japan (Nippon in Japanese).
They also found rhenium in gadolinite and molybdenite.Rhenium is a chemical element with symbol Re and atomic number 75.It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table.Rhenium has one stable isotope, rhenium-185, which nevertheless occurs in minority abundance, a situation found only in two other elements (indium and tellurium).Naturally occurring rhenium is only 37.4% Re is used for rhenium-osmium dating of ores.