Industrial grade 98% Aluminium nitrate nonahydrate CAS:7784-27-2

What is aluminum nitrate? How does it work?

Aluminium nitrate (chemical formula Al(NO3)3·9H2O, CAS 7784-27-2) is the aluminum salt of nitrate. Its most common commercial form is the nonahydrate Al(NO3)3·9H2O, a white, water-soluble, hygroscopic crystal. It is used as an aluminum tanning agent in leather tanning, an aluminum salt astringent component in antiperspirants, and an important precursor for high-purity alumina and insulating materials.

Basic information: Chemical formula Al(NO3)3·9H2O (nonahydrate, molecular weight 375.134), anhydrous Al(NO3)3 (molecular weight 212.996, CAS 13473-90-0); nonahydrate CAS number 7784-27-2, EC number 236-751-8, PubChem CID 26053, UNII HUO854648Y (anhydrous)/8MC6621V1H (nonahydrate), UN number 1438; prepared by the reaction of nitric acid and aluminum hydroxide (Al(OH)3 + 3HNO3 → Al(NO3)3 + 3H2O), or by the metathesis of aluminum salts such as aluminum nitrate with soluble nitrates.

Physically, it is a white crystalline solid with hygroscopic properties; density is approximately 1.72 g/cm³ (nonahydrate); melting point is 73.9℃ (nonahydrate, soluble in its own water of crystallization, decomposes at 150℃); it is extremely soluble in water (approximately 73.9 g/100 mL at 20℃), and also soluble in organic solvents such as methanol, ethanol, and ethylene glycol; refractive index is approximately 1.54.

Chemically, aluminum nitrate is a strong oxidizing agent (GHS H271 may cause fire or explosion, H272 supports combustion, NFPA Special Hazard OX). It poses a risk of combustion and explosion when mixed with organic matter, reducing agents, or flammable materials. Upon heating, it decomposes to release nitrogen oxides and form aluminum oxide (Al2O3)—making it an excellent precursor for the preparation of high-purity alumina. It must be stored in a sealed, moisture-proof container, away from reducing agents, organic matter, and flammable materials.

From the perspective of mechanism of action, industrial-grade aluminum nitrate exerts its effects through a triple characteristic: “coordination/complexation properties of aluminum ions + strong oxidizing properties + easy decomposition of nitrate ions”. The mechanisms of action in different applications are as follows:

Leather tanning mechanism

Al3+ coordinates and crosslinks with the carboxyl groups of the side chains of collagen, blocking the active groups of collagen and improving the shrinkage temperature, moisture and heat resistance, and softness of leather.

antiperspirant and astringent mechanism

Aluminum salt hydrolyzes to form polynuclear hydroxyaluminum complexes, which form gel-like protein-aluminum complexes at the opening of sweat gland ducts. These complexes physically astringe and block the sweat gland openings, reducing sweat secretion.

Corrosion inhibition film formation mechanism

Aluminum salts hydrolyze and deposit on metal surfaces to form a dense protective film of aluminum hydroxide/alumina, which isolates corrosive media and inhibits metal corrosion.

Precursor thermal decomposition mechanism

Heating of aluminum nitrate results in decomposition which liberates nitrate ions and gives high purity alumina (Al2O3). It is an excellent raw material for preparing alumina ceramics, insulating fillers for paper and coatings for electronic materials.

In summary, industrial-grade aluminum nitrate is a “versatile agent in aluminum chemistry”. Due to the coordination properties of aluminum ions and the easy decomposition of nitrate ions, it is used in various industries, including leather tanning, antiperspirants, petroleum refining, and alumina preparation, covering leather making, daily chemicals, corrosion prevention, oil refining, chemicals and materials.

What are the applications of industrial-grade Aluminium nitrate?

1.Leather tanning (Core application in leather industry)

Application Field: Leather processing and tanning

Corresponding Products: Aluminum tanning agents, aluminum-chromium combined tanning agents, white leather tanning agents, fur tanning agents, leather retanning agents, shoe upper and bag leather tanning agents, garment leather tanning agents

Applicability Principle: Al3+ coordinates and cross-links with the carboxyl groups of collagen side chains, raises the shrinkage temperature and hydrothermal resistance of leather, and makes leather soft, white and full-bodied.

2.Antiperspirants (major application of daily chemicals industry)

Application Field: Personal care and cosmetics

Corresponding Products: Roll-on antiperspirant, spray antiperspirant, cream antiperspirant, deodorant, underarm antiperspirant, foot antiperspirant

Applicability Principle: When aluminum salts hydrolyze, they produce polynuclear aluminum hydroxyl complexes which form astringent gels at the openings of sweat gland ducts and reduce sweat secretion. It is the main astringent ingredient in antiperspirants.

3.Metal corrosion inhibitors (field of metal corrosion protection)

Application Field: Industrial corrosion protection and metal surface treatment

Corresponding Products: Corrosion inhibitors for steel and aluminum, cooling water corrosion inhibitors, pickling inhibitors, rust inhibitors, metalworking fluid additives

Applicability Principle: Aluminum salts hydrolyze and deposit on the metal surface to form a dense alumina/aluminum hydroxide protective film, isolating corrosive media and inhibiting electrochemical corrosion.

4.Additives for petroleum refining (petroleum refining industry)

Application Field: Petroleum refining, chemical processing

Corresponding Products: Petroleum refining catalyst additives, hydrorefining additives, oil decolorizing additives, refining process additives, catalyst carrier raw materials

Applicability Principle: Aluminum nitrate can be decomposed into alumina with high specific surface area. It acts as a precursor of active components and raw material for refining catalyst carriers, participating in refining, decolorization and other refining processes.

5.Nitrating agents (fine chemical industry)

Application Field: Organic compound synthesis and fine chemical industry

Corresponding Products: Aromatic nitrating reagents, reagents for nitro compound synthesis, aids for energetic material synthesis, intermediate nitrating agents, dye intermediate nitrating agents

Applicability Principle: Aluminum nitrate can provide the NO2+ nitrating active species required for nitration, participating as a mild nitrating agent in organic chemical synthesis reactions, such as aromatic ring nitration.

6.High purity alumina and precursor materials (key applications in materials and electronics sectors)

Application Field: Electronic Materials, Inorganic Materials

Corresponding Products: High purity alumina (α-Al₂O₃), γ-alumina, nano-alumina, insulating paper filler, CRT heating element coating, transformer core lamination coating, alumina ceramics, electronic ceramics, catalyst supports

Applicability Principle: Aluminum nitrate decomposes on heating to give high purity alumina; nitrate ions escape completely without introducing impurities. It is a very good precursor for the production of insulating, electronic and ceramic grade alumina.

7.Analytical and teaching reagents (analytical chemistry)

Application Field: Analytical chemistry and education

Corresponding Products: Aluminum standard solution preparation reagents, volumetric analysis reagents, laboratory aluminum salt reagents, inorganic chemistry teaching reagents, precipitation reaction reagents, chemical experimental reagents

Applicability Principle: Aluminum nitrate has a definite composition and controllable purity. Therefore, it is a commonly used reagent in the laboratory to prepare aluminum standard solutions and carry out experiments on the chemical properties of aluminum (such as Al(NO3)3 + 3NaOH → Al(OH)3 ↓ + 3NaNO3).

Summarize

industrial-grade aluminum nitrate (Al(NO3)3·9H2O, CAS 7784-27-2) is a multi-purpose component of aluminum chemistry. Benefiting from aluminum ion coordination properties and easy decomposition of nitrate ions, it has wide applications including leather tanning, antiperspirants, metal corrosion inhibitors, petroleum refining aids, nitrating agents, high purity alumina precursor materials and analytical and teaching reagents. The main areas with the largest consumption volumes are leather tanning, antiperspirants and preparation of high-purity alumina. Warning: This product is a strong oxidizer and shall not be stored or shipped with organic matter, reducing agents or flammable materials.