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What is Aluminum Nitrate? An Overview of this Multi-Purpose Chemical

Oct 18th, 2017 by Jennifer Gilbert
What is Aluminum Nitrate? An Overview of this Multi-Purpose Chemical

Aluminum nitrate is a salt composed of aluminum and nitric acid, belonging to a group of reactive chemicals - organic nitrate and nitrite compounds. The nitrate ion is polyatomic, meaning it is composed of two or more ions that are covalently bonded. This ion makes up the conjugate base of nitric acid.

Physical Properties

Aluminum nitrate (Al(NO3)3·9H2O) normally exists as a crystalline nonahydrate in a solid or powder form. This nonahydrate form of the chemical has a melting point of 73.9°C and will decompose if exposed to higher temperatures where as the anhydrous form melts at 63°C.

Aluminum nitrate has a molecular weight of 212.996 g/mol in its anhydrous state and 375.134 g/mol in a non-anhydrous condition. Obtaining aluminum nitrate in its anhydrous form is difficult because it decomposes when heated. Due to this, it is not useful as an oxidizer in high-heat mixtures.

The chemical is both odorless and white as well as hygroscopic, meaning it readily absorbs water and moisture from the air.

Due to this, it is easily soluble in water at a rate of 73.9 g/100ml at 20°C. The resulting aquatic solutions are acidic while aluminum nitrate does not dissolve well in alcohols.


How It’s Made

The substance is typically synthesized in a reaction between nitric acid and aluminum(III) chloride. The aluminum must first be dissolved in hydrochloric acid since aluminum forms a protective layer when combined directly with nitric acid. The byproduct of this reaction is nitrosyl chloride which is released from the solution as a gas. Aluminum nitrate can also be synthesized via metathesis reaction between nitrate salt and aluminum sulfate using a cation (positively charged ion) such as silver, lead, or calcium.


What It’s Used For

Aluminum nitrate has multiple uses due to its strong oxidizing properties, high solubility, and freely available nitrogen. It is used primarily as a corrosion inhibitor to prevent things such as machinery and equipment from corroding. The chemical can be found in household items, such as most antiperspirants as well as other personal hygiene products and cosmetics. It is further used as a mordant in dyeing cotton and in tanning leather.

Its typical industrial uses are as intermediates in the production of other substances while the chemical is also applied in the extraction of Uranium and petroleum refining. In addition to this, Aluminum nitrate is used in classroom laboratory situations for displaying reactions.

The nonahydrate salts of aluminum nitrate are used in producing alumina for manufacturing insulating papers, in cathode ray tube heating elements, transformer core laminates, and are used to extract actinide elements.


Hazards and Precautions

Aluminum nitrate is nonflammable. Yet, it can accelerate the burning of other substances and may lead to an explosion as a result of prolonged contact with heat.

Although water can be used from a far distance to control such fires, when the chemical is combusted, it produces oxides of nitrogen that are toxic.  

Other mixtures to avoid include combining the substance with alkyl esters and phosphorus, tin(III) chloride, or other reducing agents as this can also cause an explosion. When mixed with acids, the chemical forms toxic nitrogen dioxide.

When handling this product, it is advisable to use proper protective equipment such as goggles, face protection, and rubber gloves in addition to dust respirators. This is because contact with the aluminum nitrate dust can irritate the eyes, nose, throat, and the skin. The dust may also irritate the lungs according to some publications, and has been labeled as harmful if inhaled.

Ingestion of large amounts of this chemical can lead to nausea, vomiting, gastric irritation, and purging. However, the chemical is not classified as a carcinogen to humans.


Storage and Disposal

The anhydrous form of aluminum nitrate should be stored in a tight-sealed container. The nonahydrate form should be kept away from moisture. The chemical seems to turn slightly yellow after sitting for years.

To dispose of the substance, any base such as a hydroxide will effectively neutralize the chemical.

Aluminum nitrate is a multi-purpose chemical applied in various industries and can be found in some common household products. It’s used primarily as an oxidizing agent in the production of other substances and prevention of erosion.


Aluminum Nitrate Distributor

With more than 35 years in the chemical supply business, Charkit’s commitment to safety and satisfaction make us an excellent choice to provide you with everything from hazardous materials like benzyl chloride, to stable specialty oils used to create high quality cosmetics. We treat all of our chemicals with special care and attention, and superior quality will show through in whatever way you use our products. If you are looking for a supplier of aluminum nitrate that you can trust for quality, Charkit is happy to provide a quote.