Boric acid is widely used in industrial, agricultural, national defense and modern science fields. In recent years, with the development of building materials industry and the increase in the export volume of boron-iron alloys, the demand for boric acid has increased. High-tech agriculture, new metallurgical materials have also promoted the development of the boric acid industry. At the same time, boric acid is also an important raw material for the manufacture of various boron compounds such as boron nitride, boron carbide, boron fibers, borane, fluoroborides, zinc borate, etc. The applications of boric acid include the following:
Boric acid is currently mainly used in the glass industry, which consumes about 42% of the world's total boric acid, and is mainly used in the manufacture of borosilicate glass, textile fiber glass, and insulating glass fiber. The addition of boric acid to optical glass, glassware, and heat-resistant glass can effectively improve the thermal expansion, improve temperature resistance, pressure resistance, mechanical strength and light transmittance of glass products, and at the same time shorten the melting time. In the case of low sodium and high aluminum, boron oxide exhibits good fluxing, so in the production of glass requiring a lower sodium content, boric acid is usually used in combination with sodium borate to adjust the ratio of sodium to boron in the glass.
Light industry textile industry and daily chemical industry
In the light industry and the daily chemical industry, boric acid is mainly used as detergent additive, bactericide and wood preservative. Boric acid can be used as bactericide for the production of boric acid soap. Boric acid can be used as an insulating material for wood preservatives and fireproof fibers. It is also a good flame retardant, for example, boric acid is used alone or in combination with borax to reduce the flammability of cotton tires and celluloid insulation materials in wood and mattresses. In addition, boric acid can also be used as a rinse agent, mordant, finishing agent, dye stabilizer in leather treatment and photography, and in the manufacture of artificial gemstones, fire-resistant fabrics, cosmetics and fragrances.
Pharmaceutical-grade boric acid is used in hygiene products and pharmaceuticals. Boric acid is a weak acid, which has almost no irritating effect on skin and mucous membranes, and it has bactericidal and disinfecting effects. The refined boric acid can be used as a heat-clearing and detoxifying agent, an analgesic disinfectant, a mouth ulcer medicine, a medical fungicide, an eye wash, a boric acid ointment, a mouthwash, an ankle disease agent, and a skin surface agent. It has recently been found that boric acid is also used for the extraction and separation of active ingredients or effective parts of herbal medicine.
The ceramics industry consumes about 11% of the world's total boric acid per year. For ceramics and enamel glazes, boron oxide is a good fluxing agent and network former for enhancing the gloss and fastness of products. It is also one of the ingredients of glazes and pigments. It forms glass at low temperatures. It can reduce the surface tension, improve the glaze adaptability, fire resistance index, mechanical strength, durability and wear resistance, and it is an important component of lead-free glaze.
Mechanical and electronic industry
When boric acid is used as an anti-oxidation negative electrode impregnant, the dry charge performance of the battery can be improved. In addition, boric acid can be used as an additive for rust inhibitors, lubricants, thermal oxidation stabilizers, brake fluids, metalworking fluids, and water treatment agents. Boric acid is required in the production of computers, automobiles, televisions and many other electronic products. Recently, countries that produce OTFT (Organic Thin-Film Transistor) liquid crystal panels have begun to develop large-screen LCD TVs. Among them, Japanese manufacturer Sharp is the dominant manufacturer, so it is believed that the demand for boric acid will increase. In recent years, the application of boric acid in luminescent materials has been highly valued by the industrialization field and the scientific community. Among the rare earth doped aluminate, silicate and borate luminescent materials, boric acid is usually used as an auxiliary or raw material.
Nuclear energy industry
High-purity boric acid is used as a reagent and a raw material for producing various high-purity borate crystals. It is a widely used chemical raw material in high-tech fields. In the nuclear industry, boron-1O isotope is a highly efficient thermal neutron absorber and is essential in safety and control systems. Boron carbide-1O and boron-1O acid are in great demand in the international market, but they are very expensive. Special grade boric acid is used in the nuclear industry and can partially replace the isotope boron-10. For general pressurized water reactors, nuclear-grade natural boric acid is mostly used as a neutron moderator, a collector, and a coolant in consideration of cost.
In agriculture, boric acid can be used to produce boron-containing micro-fertilizers. Soil fertilization in developed countries has become routine. China is a large agricultural country. According to statistics, the annual use of boron fertilizer for crops is 10 kt in China, and after applying boron fertilizer, the yield of crops is increased by 10% to 30% over the past year.
Boric acid is used as an additive for electroplating in electrochemical production, an auxiliary for electrolytic refining of nickel. In the metallurgical industry, boric acid can prevent the surface oxidation of metallic bond and copper brazing alloy, and it is also a raw material of the boron-iron alloys. In organic synthesis, boric acid can be used to synthesize polymer compounds, such as phenol formaldehyde resin and borosilicate rubber. Boric acid can also be used as a chemical reaction catalyst, for example, in the production of nylon intermediates, boric acid catalyzes the oxidation of hydrocarbons and forms esters to increase the yield of ethanol, thereby preventing further oxidation of hydroxyl groups to form ketones or hydroxy acid.