SODIUM METABORATE

Sodium metaborate is an inorganic boron compound that belongs to the borate family and is chemically defined as the sodium salt of metaboric acid.
Sodium metaborate is typically produced by the reaction of boric acid with sodium hydroxide or sodium carbonate under controlled heating conditions, resulting in an anhydrous or hydrated borate salt composed of sodium cations and metaborate anions.
Sodium metaborate alkaline character, good water solubility, and strong buffering capacity, allowing it to interact effectively with acidic species and metal surfaces in aqueous systems.

CAS Number: 7775-19-1
Molecular Formula: BNaO2
Molecular Weight: 65.8
EINECS Number: 231-891-6

Synonyms: Sodium metaborate, Borosoap, Kodalk, 7775-19-1, Boric acid (HBO₂) sodium salt, Sodium borate (NaBO₂), Sodium metaborate anhydrous, Boric acid monosodium salt, Monosodium metaborate, Z6Q395A23R, Boric acid (HBO₂) sodium salt (1:1), DTXSID2034386, CHEBI:75227, RefChem:887672, DTXCID0014386, 231-891-6, sodium;oxido(oxo)borane, SODIUMMETABORATE, Sodium(1+) (metaborato-O)-, Caswell No. 779AA, HSDB 5045, EINECS 231-891-6, EPA Pesticide Chemical Code 011104, UNII-Z6Q395A23R, NaBO₂, EC 231-891-6, SCHEMBL24708, 98536-58-4, SODIUM METABORATE [MI], SODIUM METABORATE [HSDB], SODIUM BORATE (Na₂(BO₂)₂), AKOS024426998, NS00093515, Q3333421, Boric acid (HBO2), sodium salt;Boric acid, monosodium salt;Monosodium metaborate;NaBO2;Rasorite;Sodium dioxoborate;SODIUM MONOBORATE;SODIUM METABORATE

Sodium metaborate is used in the manufacturing of borosilicate glasses. 
It is also a component of herbicides and antifreeze. 
Sodium metaborate can also be used as an oil additive with anti-wear properties. 

Sodium metaborate electroreduction in the alkaline system can act as a novel desulphurization process of coal water slurry. 
It also has role in hydrolysis of sodium borohydride to minimize the water utilization. 
Sodium metaborate can also act as a novel alkali in alkali/surfactant/polymer flooding5. 

Sodium metaborate is also useful in the thermo-chemical production of sodium borohydride6, which is a safe and practical hydrogen storage material for on-board hydrogen production.
Sodium metaborate is a chemical compound of sodium, boron, and oxygen with formula NaBO2.
However, the metaborate ion is trimeric in the anhydrous solid, therefore a more correct formula is Na3B3O6 or (Na+)3[B3O6]3−. 

The formula can be written also as Na2O·B2O3 to highlight the relation to the main oxides of sodium and boron.
The name is also applied to several hydrates whose formulas can be written NaBO2·nH2O for various values of n.
Sodium metaborate is an inorganic boron-containing compound that belongs to the borate family and is chemically defined as the sodium salt of metaboric acid, generally expressed by the formula NaBO₂.

Sodium metaborate is commonly manufactured by neutralizing boric acid with sodium hydroxide or sodium carbonate under controlled thermal conditions, during which dehydration reactions occur and yield anhydrous or hydrated forms of sodium metaborate depending on temperature and stoichiometry.
The compound consists of sodium ions (Na⁺) and metaborate anions (BO₂⁻), forming a stable ionic lattice typical of alkali metal borates.

This ionic borate structure imparts sodium metaborate with strong alkaline character, good water solubility, and notable buffering capacity across a wide pH range.
When dissolved in water, metaborate species interact with hydroxyl ions, allowing the compound to neutralize acids and maintain stable alkaline conditions in solution.
The presence of boron–oxygen bonds also provides relatively high thermal stability and resistance to chemical degradation under normal industrial handling conditions.

From a functional standpoint, sodium metaborate is widely used in detergents, cleaning agents, and industrial washing formulations as a pH regulator and alkalinity source.
Its alkaline nature and borate chemistry contribute to enhanced cleaning efficiency, soil dispersion, and protection of metal surfaces from corrosion during washing processes.
In metal treatment and corrosion inhibition applications, sodium metaborate can form protective borate layers on metal surfaces, reducing oxidative and electrochemical attack.

Melting point : 966 °C
Boiling point : 1434 °C
Density : 2.464
Solubility : Soluble in H₂O
pKa : 8.94 (20 °C)
Form : White hexagonal crystals
Color : White, hexagonal crystalline
Water solubility : g/100 g H₂O — 14.10 (0 °C), 22.00 (25 °C), 55.60 (100 °C); solid

Sodium metaborate is an inorganic boron compound that belongs to the borate family and is chemically defined as the sodium salt of metaboric acid, most commonly represented by the formula NaBO₂.
Sodium metaborate is typically produced by reacting boric acid with sodium hydroxide or sodium carbonate at elevated temperatures, during which dehydration and neutralization reactions lead to the formation of anhydrous or hydrated sodium metaborate depending on processing conditions.
The compound is composed of sodium cations (Na⁺) and metaborate anions (BO₂⁻), forming a stable ionic structure characteristic of alkali metal borates.

This ionic borate structure gives sodium metaborate distinctly alkaline properties, along with good solubility in water and strong buffering behavior over a wide pH range.
In aqueous solution, metaborate species can interact with water and hydroxyl ions, enabling sodium metaborate to neutralize acids and maintain pH stability in chemical formulations.
The presence of boron–oxygen bonds also contributes to its thermal stability and chemical resistance under normal storage and handling conditions.

Because of these properties, sodium metaborate is widely used in industrial and chemical applications where alkalinity, buffering capacity, and boron functionality are required.
It is commonly employed in detergents, cleaning agents, and industrial formulations as a pH regulator and corrosion-inhibiting additive, particularly in water-based systems.
Its ability to interact with metal surfaces and form protective borate layers makes it useful in corrosion control and metal-processing applications.

In addition, sodium metaborate serves as a source of boron in chemical synthesis, glass and ceramic processing, and specialty formulations where controlled boron release is desired.
Sodium metaborates inorganic borate structure, alkaline behavior, and aqueous compatibility makes sodium metaborate a versatile and important compound in industrial chemistry and materials-related applications.

Sodium metaborate is also used as a boron source in glass, ceramic, and enamel formulations, where borates help control melting behavior, improve thermal stability, and enhance chemical durability of the final materials.
In chemical manufacturing, it serves as an intermediate or additive in specialty formulations that require controlled boron content and stable alkaline conditions.
Sodium metaborates inorganic borate structure, alkaline buffering behavior, thermal stability, and water compatibility makes sodium metaborate a versatile compound in industrial chemistry, materials processing, and formulation science.

Uses:
Sodium metaborate is widely used as an alkaline additive and buffering agent in industrial and household formulations where stable pH control is required.
In detergents and cleaning products, it improves cleaning efficiency by increasing alkalinity, aiding in soil removal, grease dispersion, and protection of metal components from corrosion during washing processes.
Sodium metaborate is commonly applied in metal treatment and corrosion inhibition systems, where metaborate species interact with metal surfaces to form protective borate layers that reduce oxidation and electrochemical degradation.

This makes sodium metaborate useful in cooling-water systems, metalworking fluids, and industrial cleaning baths.
Sodium metaborate is also used as a source of boron in glass, ceramic, and enamel manufacturing, where borates help lower melting temperatures, improve thermal shock resistance, and enhance chemical durability of the final products.
In these applications, it contributes to improved processing efficiency and material performance.

In chemical and industrial formulations, sodium metaborate serves as a pH regulator, neutralizing agent, and stabilizer in processes that require controlled alkaline conditions.
Sodium metaborate is further employed in specialty products such as flame retardant systems, wood preservation formulations, and agricultural or industrial chemicals where boron functionality is required.
Sodium metaborate is extensively used as an alkaline agent and buffering component in a wide range of industrial and household formulations that require stable and controlled pH conditions.

In detergents and cleaning products, it enhances washing performance by increasing alkalinity, improving soil and grease removal, and helping to protect metal surfaces from corrosion during cleaning cycles.
In metal-processing and corrosion-inhibition applications, sodium metaborate is added to cooling-water systems, metalworking fluids, and industrial cleaning baths.
The metaborate ions can interact with metal surfaces to form protective borate layers, reducing oxidative attack and electrochemical corrosion, particularly in alkaline environments.

Sodium metaborate is also widely used as a boron source in the manufacture of glass, ceramics, enamels, and fiberglass.
In these materials, borates help control melting behavior, reduce processing temperatures, improve thermal stability, and enhance the chemical durability of the finished products.
In chemical manufacturing and formulation science, sodium metaborate functions as a pH regulator, neutralizing agent, and stabilizer in reactions and processes that require consistent alkaline conditions.

It is used in specialty formulations such as adhesives, coatings, and sealants, where controlled alkalinity and boron chemistry contribute to product stability and performance.
Additionally, sodium metaborate is applied in flame-retardant systems, wood preservation treatments, and certain agricultural or industrial chemical formulations where boron compounds provide protective or functional benefits.
Sodium metaborates combination of alkalinity, buffering capacity, boron content, and aqueous compatibility makes sodium metaborate a versatile additive across cleaning, materials processing, and industrial chemistry applications.

Safety Profile:
Sodium metaborate is generally classified as a moderate hazard inorganic alkaline substance and should be handled with appropriate safety precautions.
Due to its alkaline nature, direct contact with the solid or concentrated solutions can cause skin and eye irritation, with eye exposure potentially leading to redness, pain, or serious irritation if not promptly rinsed.
Inhalation of dust may irritate the respiratory tract, causing coughing, throat discomfort, or shortness of breath, especially in poorly ventilated environments.

Ingestion can be harmful, as sodium metaborate may cause gastrointestinal irritation, including nausea, vomiting, and abdominal discomfort due to its alkalinity and boron content.
Prolonged or repeated exposure to boron-containing compounds may pose systemic health risks, particularly affecting the reproductive system at high doses, as indicated in toxicological studies on borates.
For this reason, occupational exposure limits and proper handling guidelines should be followed in industrial settings.

Sodium metaborate is non-flammable and thermally stable under normal conditions, but it can decompose at high temperatures to release boron oxides and other boron-containing fumes.
Standard safety measures include the use of protective gloves, eye protection, dust masks or respirators when handling powders, and adequate ventilation.
Spills should be cleaned carefully to avoid dust formation, and disposal should comply with local environmental regulations, as high concentrations of borates may be harmful to aquatic organisms.