Physical Properties
Colorless crystals or white powder; monoclinic structure; very hygroscopic; melts at 837°C; decomposes above 900°C; very soluble in water.
Uses
Rubidium carbonate is used in special glass and in fiber optics. It enhances stability and durability of glass, reducing its conductivity. It also is used in the preparation of Rb metal and other rubidium salts.
Preparation
Rubidium carbonate is an intermediate in recovery of rubidium from lepidolite. The mineral, on prolonged heating with concentrated sulfuric acid, converts to alums.
The mixed alum solution, on treatment with ammonia or potassium carbonate, forms carbonates of potassium, rubidium and cesium. Rubidium carbonate is separated from other alkali metal carbonates by fractional crystallization (see Rubidium)
The carbonate salt also may be obtained by passing carbon dioxide through a solution of rubidium hydroxide in a fluorocarbon or nickel container. The solution is evaporated to yield the product carbonate.
Also, the salt may be prepared by adding ammonium carbonate to a solution of rubidium hydroxide. The solution is evaporated to dryness to expel ammonia.
Description
Rubidium carbonate is a white powder or colorless crystal with a monoclinic crystal structure. Its chemical formula is Rb
2CO
3. Rubidium is often sold as rubidium carbonate The chemical properties of rubidium carbonate are stable. Rubidium carbonate is very hygroscopic, soluble in water, and insoluble in alcohol. It can be converted to other rubidium compounds by heating or by reacting with acids. Rubidium carbonate is used in the preparation of rubidium metal, other rubidium salts,and rubidium single crystals. It is also used as a specific glass additives, catalysts, analytical reagents and others. For example, rubidium carbonate can be incorporated into the metal oxide electron transport layers, which can improve the lifetime of quantum-dot light emitting diodes
[1]. It can also exist as an alkaline in the high-temperature nucleophile synthesis of a semi-crystalline, aromatic poly(ether ketone)
[2].
Chemical Properties
White powder.Extremely
hygroscopic; soluble in water. Dissociates above
900C. The thermal decomposition of rubidium carbonate to produce rubidium oxide and carbon dioxide. This reaction takes place at a temperature of over 900°C in vacuo. The decomposition of Rb2CO3·3H2O2 and Cs2CO3·3H2O2 under isothermal conditions was studied (55–85°) and it was shown that the decomposition of these compounds is self-accelerated. The final products are M2CO3, H2O, and O2. Rb2CO3·3H2O2 has a much higher thermal stability than Cs2CO3·3H2O2.
Uses
Special glass formulations.
Uses
Rubidium carbonate is used as a raw materials for preparation of rubidium metal and various rubidium salts, for the manufacturing of special glass, for the manufacturing of high energy density micro cells and crystal scintillation counters. It is also used as a part of a catalyst for preparing short-chain alcohols from feed gas.
Hazard
Strong irritant to tissue.
References
[1] Yujin Lee, Hyo-Min Kim, Jeonggi Kim, Jin Jang, Remarkable lifetime improvement of quantum-dot light emitting diodes by incorporating rubidium carbonate in metal-oxide electron transport layers, Journal of Materials Chemistry C, 2019, 7, 10082-10091.
[2] Kate JC Lim, Paul Cross, Peter Mills, Howard M Colquhoun, Controlled variation of monomer sequence distribution in the synthesis of aromatic poly(ether ketone)s, 2016, 28.
