Physical Properties
Grayish-white porous mass; cubic crystalline structure; refractive index 1.810; vaporizes above 3,000°C; reacts with water forming strontium hydroxide, Sr(OH)2 with evolution of heat; miscible with fused caustic potash; slightly soluble in alcohol; insoluble in acetone and ether.
Uses
Strontium oxide is an alkaline earth flux that melts at 4406°F(2430°C), but the substance begins its fluxing action above 1994°F(1090°C). Strontium oxide's properties are difficult to describe, so it's often compared to other alkaline earth oxides like calcium and barium oxides. It has similarities to both. Strontium oxide has fluxing properties and a strong color response like barium oxide, although not as intense. It adds strength and durability to a glaze like calcium oxide and it melts very slowly, thus increasing the melting range of a glaze.
Strontium oxide is often substituted for toxic barium oxide. A typical substitution is 0.75 grams of Strontium carbonate for 1 gram barium carbonate; keep in mind that it won't produce the same color response as barium oxide.
Strontium has a moderate viscosity and surface tension and a moderate to high expansion and contraction rate that's similar to calcium oxide.It's not volatile at ceramic temperatures, is slightly soluble,and has no known toxicity.
A slightly soluble source of strontium oxide is strontium carbonate, which usually contains some CaO.
Preparation
Strontium oxide is prepared by thermal decomposition of strontium carbonate, hydroxide, or nitrate:
SrCO3 → SrO + CO2
Sr(OH)2 → SrO + H2O
Sr(NO3)2 → SrO + N2O5
Description
Strontium Oxide, SrO, is a metal oxide usually produced by the reaction of strontium with oxygen. It can also be prepared by the decomposition of heated strontium carbonate, hydroxide, or nitrate and is used in manufacturing other strontium salts, in pigments, soaps and greases, and as a drying agent. It is commonly used in the glass, ceramics, and electronic industries and has other specific uses, such as fuel cells and sputtering target material. If burn strontium under general conditions with air, strontium oxide and strontium nitride will form. Strontium oxide was once required by law as the material used on old TV face-plates to block harmful X-ray emissions. BaO and SrO were reported for the transesterification of palm oil for the production of biodiesel. The reaction was conducted under ultrasound conditions to ensure the effective production of biodiesel.
Chemical Properties
white to grayish white; reacts with water, forming Sr(OH)2, with evolution of heat; enthalpy of fusion 75.00kJ/mol [MER06] [CRC10]
Physical properties
Strontium oxide
or strontia, SrO, is formed when Sr metal reacts with
oxygen:
2Sr＋ O2→2SrO
Burning strontium in air results in a mixture of strontium
oxide and strontium nitride. It also forms from the
decomposition of strontium carbonate SrCO3. It is
a strongly basic oxide. It reacts
with moisture forming the hydroxide and with carbon
dioxide in the air to form the carbonate.
Uses
Strontium oxide is used as a flux in the making of glass for television tubes in place of barium oxide [CAS: 1304-28-5] BaO.
Uses
SrO is also used in medicine, pyrotechnics, pigments, greases, soaps, and as a chemical intermediate. It is also produced as high-purity strontium oxide rotatable sputtering targets with the highest possible density and smallest possible average grain sizes for use in semiconductor, photovoltaic, and coating applications by chemical vapor deposition and physical vapor deposition and optical applications.One of the reasons why rare metals are restrained from wide use in production is their high cost.
Uses
manufacture of strontium salts.
Flammability and Explosibility
Not classified
