Aluminium acetate

Aluminium acetate or aluminium ethanoate^[1] (also "aluminum ~"), sometimes abbreviated AlAc in geochemistry,^[2] can refer to a number of different salts of aluminium with acetic acid. In the solid state, three salts exist under this name: basic aluminium monoacetate, (HO)₂AlCH₃CO₂, basic aluminium diacetate, HOAl(CH₃CO₂)₂,^[3] and neutral aluminium triacetate, Al(CH₃CO₂)_3.^[3] In aqueous solution, aluminium triacetate hydrolyses to form a mixture of the other two,^[1] and all solutions of all three can be referred to as "aluminium acetate" as the species formed co-exist and inter-convert in chemical equilibrium.

Stoichiometry

Monoacetate

Main article: Aluminium monoacetate

Aluminium monoacetate, also known as dibasic aluminium acetate, forms from Al(OH)₃ and dilute aqueous acetic acid. More concentrated acid leads to the di- and triacetate.^[4]

Diacetate

Main article: Aluminium diacetate

Aluminium diacetate, also known as basic aluminium acetate, is prepared from aqueous aluminium acetate solution resulting in a white powder.^[5] This basic salt forms from the hydrolysis of the triacetate in water.^[1]

Triacetate

Main article: Aluminium triacetate

Aluminium triacetate is a chemical compound that is prepared by heating aluminium chloride (AlCl₃) or Al powder with a mixture of acetic acid (CH₃COOH) and acetic anhydride (C₄H₆O₃).^[5] It is referred as the normal salt and is only made in the absence of water at a relatively high temperature like 180 °C.^[1]