Anhydrous aluminum chloride is a white or pale yellow crystalline powder. Industrial grade products may appear pale yellow, yellowish green or reddish brown due to impurities such as iron and free chlorine.It is highly hygroscopic and reacts violently with water or moist air, releasing a large amount of heat and corrosive hydrogen chloride fumes to form acid mist.As a typical strong Lewis acid, it exhibits extremely high activity in organic synthesis. It exists as a dimer (Al₂Cl₆) in vapor and molten states.

1. Organic Synthesis Catalyst: The primary application. Used in Friedel-Crafts alkylation and acylation reactions; a key catalyst for the synthesis of ethylbenzene, anthraquinone dyes, and pharmaceutical intermediates.
2. Petrochemical Industry: Used as a catalyst in petroleum cracking and hydrocarbon isomerization to improve gasoline octane rating.
3. Fine Chemical Industry: Used in the production of synthetic resins, synthetic rubbers, detergents, fragrances, pesticides, etc.
4. Metal Smelting: Used as a flux in aluminum electrolysis and an auxiliary agent in the smelting of other metals.
5. Others: Lubricating oil treatment, rubber vulcanization, flame retardant synthesis, water treatment (hexahydrate), etc.