Sodium hypophosphite, characteristics, production, application

2024 Author: Angel Austin | [email protected]. Last modified: 2023-12-17 05:14

Sodium phosphinate (NaPO₂H₂, also known as sodium hypophosphite) is the sodium s alt of hypophosphoric acid and is often found as NaPO monohydrate ₂H₂ H₂O. It is a solid that is white, odorless crystals at room temperature. Decomposes when heated above 260°C.

It absorbs moisture from the air, and is easily soluble in water, in an aqueous solution it decomposes when heated (2NaH₂PO₂→ NaHPO₄+PH₃), releasing hydrogen peroxide. Sodium hypophosphite should be stored in a cool, dry place, isolated from oxidizing agents. Decomposes into phosphine, which irritates the respiratory tract, and disodium phosphate.

Features

Molar mass	87, 96 g/mol
Physical Condition	to be determined
density	1.77g/cm³
melting point	310 °C (decomposition of monohydrate)
solubility	744 g/l at 20°C soluble in ethanol

Receive

1. You can get it in the following way:
2. Sodium phosphinate can be obtained by the reaction of white phosphorus with caustic soda: Р₄+3NaOH+3H₂O→Na 2_HPO4_+PH3_{↑ (synthesis of sodium hypophosphite, formula).}
3. Oxidation of phosphine with sodium hypochlorite: РН₃+2NaClO+NaOH→Na(РН₂O_2)+2NaCl+H2_O.
4. Decomposition of calcium phosphinate with sodium carbonate: Ca(PH₂O₂)+NaOH→Na(PH₂ O₂)+CaCO₃↓.
5. It can be prepared by neutralizing hypophosphoric acid or calcium phosphinate solution with sodium carbonate: H(PH₂O₂)+NaOH→Na (PH₂O₂)+N₂O.

In the reaction in aqueous solutions, a monohydrate is formed.

Use

Scope:

1. Sodium hypophosphite (SHP) acts as a reducing agent to supply the electrons required for the EN process. The EN process allows you to obtain a uniform coating thickness not only on metal objects, but also on plastics and ceramics. With this method, a long-lasting nickel-phosphorus film can cover uneven surfaces, such as in avionics, aviation, andin oil fields. SHP is able to reduce nickel ions in solution to nickel metal on metal substrates as well as on plastic substrates. The latter requires that the substrate be activated by fine palladium particles. As a result, the nickel deposit contains up to 15% phosphorus.
2. As a raw material in the manufacture of other products, including hypophosphorous acid. It can be used in synthetic organic chemistry, especially in deamination by reduction of diazo derivatives.
3. SHP can be used as a reducing agent or antioxidant in chemical processing.
4. SHP is used as a stabilizer to prevent degradation of polymers during extrusion or other hot working.
5. Sodium phosphinate is used as a Thiele reagent for the detection of selenium.
6. Sodium hypophosphite can be used as a partial flame retardant. This will provide a source of electrons in resin regeneration.
7. Polymerization catalyst.
8. Polymer stabilizer.

He alth effects

Allergic skin reactions may occur in some people after repeated skin exposure to sodium hypophosphite. Additional data on the ability to cause toxic effects in humans are not available. It does not cause skin or eye irritation in laboratory animals. No toxic effects have been observed with oral ingestion or moderate to high concentration skin exposure.

Reduced activity has been observed in laboratory animals exposed to extremely high oral doses of sodium hypophosphite. Some animals died. No signs of infertility, abortion or birth defects have been observed in laboratory animals following oral exposure prior to and/or during pregnancy. Data on the ability to cause cancer in laboratory animals are not available. The potential of sodium hypophosphite to cause cancer in humans has not been evaluated. However, it is recommended to use protective equipment when handling the substance.