Ammonium Perrhenate Cas:13598-65-7

Rhenium compound ammonium perrhenate, also known as ammonium perrhenate, commonly known as ammonium rhenate. A white hexagonal cubic bipyramidal crystal, molecular formula NH4ReO4, molecular weight 268.242, decomposition before melting point, relative density 3.97. It is one of the many salt compounds formed by rhenium element, and it is also the most widely used rhenium compound in industry. Method: It can be obtained by saturating perrhenic acid solution with ammonia gas or adding ammonium sulfate or ammonium carbonate solution to barium perrhenate solution.
Uses: Used as oxidizing agent, can also be used as rhenium tungsten wire raw material.

Elemental rhenium
Rhenium is a group Xavier element of the sixth cycle of the periodic table, a rare high melting point metal. Element symbol Re, atomic number 75, relative atomic mass 186.207. Dense massive metal rhenium is silver-white. Physical properties: the melting point of rhenium is second only to carbon and tungsten, the density and boiling point rank first among all elemental substances, and the resistivity is 3 times larger than tungsten.
Rhenium has high hardness, high mechanical strength and good plasticity, and is easy to draw and roll at room temperature, but it cannot be subjected to hot processing.

Chemical properties: Powdered rhenium is stable in room temperature air, easy to burn when heated, and will be violently oxidized to Re2O7 at temperatures higher than 873K. Block rhenium is also stable at room temperature and oxidizes to the volatile Re2O7 at 1273K. Rhenium does not react with hydrogen, nitrogen, and carbon, but rhenium powder can absorb hydrogen. Rhenium reacts with sulfur vapor to form ReS2, the reaction rate of which accelerates with increasing temperature. In an oxygen-free atmosphere, heated rhenium can react with fluorine, chlorine and bromine to form the corresponding halides ReF6, ReF7, ReCl3, ReCl5 and ReBr3. Compounds: Rhenium compounds are varied, divided into inorganic rhenium compounds, rhenium metal cluster compounds and organic rhenium compounds. Inorganic rhenium compounds include oxides, perrhenic acids and their salts, sulfides, halides and carbon-based compounds. Oxides are ReO4, ReO7, ReO3, Re2O5, ReO2, Re2O3, ReO and Re2O, among which the more stable are Re2O7, ReO3 and ReO2. HReO4 perrhenate and its main salts are potassium perrhenate, sodium perrhenate, calcium perrhenate and ammonium perrhenate. Rhenium sulfides are Re2S7, ReS3, ReS2, Re2S3 and ReS, of which only Re2S7 and ReS2 are more stable.