Boric Acid, Orthoboric Acid, Boron Acid, Boron Hydroxide, Boron Trihydroxide, Homberg Salt, 10043-35-3, 11113-50-1

Boric Acid, Orthoboric Acid, Boron Acid, Boron Hydroxide, Boron Trihydroxide, Homberg Salt, 10043-35-3, 11113-50-1

BORIC ACID (Orthoboric Acid)

1. PRODUCT DEFINITION AND CHEMICAL IDENTITY

Note: Boric acid is a naturally occurring boron compound. Turkey holds approximately 72% of the world's boron reserves. It is obtained from boron minerals, primarily colemanite, by reaction with sulfuric acid. It is a weak acid with mild antiseptic, antifungal, and antiviral properties.

2. PHYSICAL AND CHEMICAL PROPERTIES

3. THERMAL BEHAVIOUR

4. FUNCTIONAL PROPERTIES

• Weak acid / Buffering agent: Forms borate ions in aqueous solution; together with borax, creates buffer systems across a wide pH range.

• Antimicrobial / Antiseptic: Effective against bacteria (Staphylococcus aureus, Listeria monocytogenes), fungi, and viruses.

• Pesticide: Corrosive and dehydrating effect on insect exoskeletons; also acts as a stomach poison when ingested.

• Fire retardant: Releases water when heated and promotes cellulose dehydration, preventing flame spread.

• Flux: Dissolves metal oxides, facilitating soldering and welding processes.

• Micronutrient source: Essential boron source for plants; component of boron-molybdenum fertilisers.

• Glass and ceramic additive: Increases thermal resistance; regulates viscosity and reduces crystallisation.

5. ALTERNATIVE NAMES AND SYNONYMS (Comprehensive List)

• Boric acid (fundamental English name)

• Boracic acid (common English)

• Orthoboric acid (IUPAC)

• Trihydroxyborane / Boron trihydroxide (chemical description)

• Hydrogen orthoborate

• Homberg's salt (historical name)

• Trade names: Borofax, Optibor, Optibor TP, BorActin, Basilit B, Niban, Entimaden, CB BORiD, PS 1002

• Pesticide trade names: Roach Prufe, Flea Prufe, Niban-FG, Niban Granular Bait, Roach Away, Bushwhacker, Super Flea Eliminator, Dia Flea-Mate

• NSC 81726 (National Chemical Substance code)

6. PRODUCTION PROCESS

Boric acid is obtained primarily from boron minerals, chiefly colemanite (Ca₂B₆O₁₁·5H₂O).

Main Reaction:
2Ca₂B₆O₁₁·5H₂O + 4H₂SO₄ + 17H₂O → 4CaSO₄·2H₂O (gypsum) + 6H₃BO₃ (boric acid)

Production Stages:

1. Crushing and grinding of the ore

2. Controlled reaction with sulfuric acid

3. pH and temperature adjustment

4. Filtration to separate gypsum

5. Crystallisation and purification

6. Drying and packaging

7. SECTORAL APPLICATIONS, USAGE RATES, AND EXAMPLE FORMULATIONS

Example Formulations:

• Simple Eye Wash Solution (2%):

  • Boric acid: 2 g

  • Sterile purified water: 100 mL
    Dissolve boric acid in hot water, cool, and filter into a sterile bottle. For external use only.

• Cockroach Control Bait:

  • Boric acid: 10%

  • Powdered sugar: 45%

  • Flour: 45%
    Place in small shallow trays in dry areas. Keep away from children and pets.

• Wood Preservation Impregnation Solution:

  • Boric acid: 100 g

  • Borax (decahydrate): 100 g

  • Water: 1 L
    Dissolve thoroughly; apply to wood by brush or dipping. Apply a second coat after drying.

• Metal Soldering Flux (Jeweller's Type):

  • Boric acid: 50 g

  • Borax: 30 g

  • Water: 30 mL (to form a paste)
    Apply a thin layer to the metal surface during soldering.

8. ALTERNATIVES AND COMPARISON

9. REGULATORY STATUS, SAFETY, AND ENVIRONMENT

• GHS Classification (CLP Regulation):

  • Signal word: Danger

  • Hazard statements:

    • H360FD: May damage fertility. May damage the unborn child.

  • Precautionary statements: P201, P202, P280, P308+P313, P405, P501.

• NFPA 704: Health: 1, Flammability: 0, Reactivity: 0.

• Food additive (E284): Historically used, but now banned as a food additive in most countries. Ingestion can cause toxic effects.

• Cosmetic use: The EU Cosmetics Regulation restricts boron compounds. Only permitted in specific product categories and within limit values.

• Pharmaceutical use: Permitted in prescription and OTC products for specific indications; overdose must be avoided.

• Environmental impact: Naturally occurring in the earth's crust; however, toxic to aquatic life and plant growth at high concentrations. Do not discharge into drains or watercourses.

• Storage: Keep in a cool, dry, well-ventilated area in tightly sealed containers. Keep out of reach of children and pets. Store separately from food and feedstuffs.

• Personal protection: Avoid breathing dust; wear protective gloves and goggles. In case of skin contact, wash with plenty of water.

10. TOXICOLOGICAL PROFILE (Summary)

11. FREQUENTLY ASKED QUESTIONS

Q1. Are boric acid and borax the same?
No. Boric acid (H₃BO₃) is a weak acid; borax (Na₂B₄O₇·10H₂O) is the sodium tetraborate salt. Boric acid has a more acidic character (pH ~5), while borax is alkaline (pH ~9). Their chemical and physical properties and application areas differ.

Q2. Is boric acid safe for the eyes?
Yes, at low concentration (1–2%) as a sterile solution, it is used in eye washes and contact lens solutions. However, higher concentrations are irritant. Always use pharmacy-quality, sterile product.

Q3. How does boric acid kill insects?
It acts in two ways: (1) It has a corrosive effect on the insect exoskeleton, causing them to lose water (dehydration). (2) When ingested, it acts as a stomach poison, affecting the nervous system.

Q4. Is boric acid carcinogenic?
According to available data, boric acid is not classified as carcinogenic. Some in vitro studies have even shown anti-proliferative effects (inhibiting cancer cell growth); however, further research is needed.

Q5. Can boric acid be used during pregnancy?
No. Boric acid is classified as H360FD (May damage fertility. May damage the unborn child). The use of products containing boric acid is not recommended during pregnancy and breastfeeding.

Q6. How should boric acid be stored?
Store in a cool, dry, well-ventilated area in the original tightly sealed container. Protect from moisture. Keep away from foodstuffs and out of reach of children.

Q7. Which metals are incompatible with boric acid?
Boric acid can react slowly with base metals (zinc, aluminium, iron), especially in moist environments. Stainless steel, plastic (PE, PP), or glass containers are recommended for storage.

12. QUICK REFERENCE TABLE