Usage areas of Sodium Molybdenum
Sodium Molybdenum is one of the transition metals and is silvery white in pure form and very hard. The melting temperature is quite high. Further hardening of the steel can be achieved by adding a small amount. Molybdenum is also important in the nutrition of plants and takes place in some enzymes.
Swedish chemist Carl Wilhelm Scheele demonstrated in 1778 that the mineral (molybdenite), which until then was thought to be a lead ore or graphite, was a sulfide compound of an unknown metal. Swedish chemist Peter Jacob Hjelm also separated molybdenum into metal in 1782 and named it after the Greek word molybdos, meaning “lead-like”.
Although molybdenum is found in minerals such as wulfenite (PbMoO4) or powellite (CaMoO4), the main commercial source of molybdenum is molybdenite (MoS2). Molybdenum can also be obtained through direct mining and as a by-product during copper mining. Molybdenum is found in its ores in amounts ranging from 0.01% to 0.5%. About half of the world’s molybdenum mining is done in the USA (Phelps Dodge Corporation).
Molybdenum, which is similar to chromium and wolfram in terms of chemical properties; It has superior properties such as high melting and boiling point, high heat resistance, high thermal conductivity and low thermal expansion. Molybdenum melts at 2623 °C. With this feature, it takes the sixth place among metals. Boiling at 4639 °C, molybdenum is not affected by air in the cold, oxidized when incandescent, affected by nitric and sulfuric acids, and decomposes water vapor at high temperatures. The density of molybdenum is 10.28 gr/cm3.
- The agricultural industry uses a £1 million fertilizer per year. In particular, it has been proposed to be used for processing broccoli and cauliflower seeds on molybdenum-deficient soils.
- However, care should be taken as sodium molybdate at a level of 0.3 ppm can cause copper deficiencies in animals, particularly cattle.
- It is used in industry for corrosion prevention because it is a non-oxidizing anodic inhibitor.
- The addition of sodium molybdate significantly reduces the nitrite requirement of nitrite-amine inhibited fluids and improves the corrosion protection of carboxylate salt fluids.
- In industrial water treatment applications where galvanic corrosion is potential due to the bimetallic structure, sodium molybdate is preferred rather than sodium nitrite.
- Sodium molybdate has the advantage that lower ppm molybdate dosing has lower conductivity of circulating water. Sodium molybdate at 50-100 ppm offers the same levels of corrosion inhibition as sodium nitrite at 800 + ppm.
- By using lower concentrations of sodium molybdate, conductivity is kept to a minimum and thus galvanic corrosion potentials are reduced.