Aluminium nitrate is a white, water-soluble

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

and

nitric acid Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitri ...

, most commonly existing as the crystalline hydrate, aluminium nitrate nonahydrate, Al(NO₃)₃·9H₂O.

Preparation

Aluminium nitrate cannot be synthesized by the reaction of aluminium with concentrated nitric acid, as the aluminium forms a passivation layer. Aluminium nitrate may instead be prepared by the reaction of

with aluminium(III) chloride.

Nitrosyl chloride Nitrosyl chloride is the chemical compound with the formula NOCl. It is a yellow gas that is commonly encountered as a component of aqua regia, a mixture of 3 parts concentrated hydrochloric acid and 1 part of concentrated nitric acid. It is a st ...

is produced as a by-product; it bubbles out of the solution as a gas. More conveniently, the salt can be made by reacting

with

aluminium hydroxide Aluminium hydroxide, Al(OH)3, is found in nature as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic an ...

. Aluminium nitrate may also be prepared a metathesis reaction between aluminium sulfate and a nitrate salt with a suitable cation such as barium, strontium, calcium, silver, or lead. e.g. Al₂(SO₄)₃ + 3 Ba(NO₃)₂ → 2 Al(NO₃)₃ + 3 BaSO₄.

Uses

Aluminium nitrate is a strong oxidizing agent. It is used in

tanning Tanning may refer to: *Tanning (leather), treating animal skins to produce leather *Sun tanning, using the sun to darken pale skin **Indoor tanning, the use of artificial light in place of the sun **Sunless tanning, application of a stain or dye t ...

leather, antiperspirants,

corrosion inhibitor In chemistry, a corrosion inhibitor or anti-corrosive is a chemical compound that, when added to a liquid or gas, decreases the corrosion rate of a material, typically a metal or an alloy, that comes into contact with the fluid. The effectiveness ...

s, extraction of

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

petroleum refining An oil refinery or petroleum refinery is an industrial process plant where petroleum (crude oil) is transformed and refined into useful products such as gasoline (petrol), diesel fuel, asphalt base, fuel oils, heating oil, kerosene, liquefi ...

, and as a nitrating agent. The nonahydrate and other hydrated aluminium nitrates have many applications. These salts are used to produce alumina for preparation of insulating

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distrib ...

s, in cathode ray tube heating elements, and on

transformer A transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple circuits. A varying current in any coil of the transformer produces a varying magnetic flux in the transformer' ...

core laminates. The hydrated salts are also used for the extraction of

actinide The actinide () or actinoid () series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The actinide series derives its name from the first element in the series, actinium. The info ...

elements.Pradyot Patnaik. ''Handbook of Inorganic Chemicals''. McGraw-Hill, 2002, . It is used in the laboratory and classroom such as in the reaction : Al(NO₃)₃ + 3 NaOH → Al(OH)₃ + 3 NaNO₃ It is, however, much less often encountered than aluminium chloride and aluminium sulfate.

References

External links

MSDS of nonahydrate

Government of Canada Fact Sheets and Frequently Asked Questions: Aluminum Salts
{{Authority control Aluminium compounds Nitrates Deliquescent substances Oxidizing agents