The Many Aluminum Chloride Uses in Industrial Chemistry
Aluminum chloride is a chemical compound derived from chlorine and aluminum. It has a variety of applications in manufacturing processes in both its hydrous and anhydrous forms. The compound is considered to be a highly versatile, inorganic substance that can be used as a catalyst in chemical reactions and syntheses required for the production of various products.
Uses for Anhydrous Aluminum Chloride in Chemical Reactions
Among the most important uses of the compound is its role as a catalyst in Freidel-Crafts reactions. Because of its strong Lewis acid properties, anhydrous aluminum chloride is used in both alkylations and acylations. In the Friedel-Crafts reactions, it is used to prepare anthraquinone, which is commonly used in the dyestuffs industry. To produce the resultant compounds, acyl chloride or Alkyl halide are made to react with an aromatic system.
Problems with Using Aluminum Chloride in Friedel-Crafts Reactions
One of the issues of using aluminum chloride in Friedel-Crafts reactions is that the compound complexes with the other products in the reaction strongly, hence it often has to be used in full stoichiometric quantities. However, this problem leads to a large amount of corrosive waste. Disposing of this waste can often be a dangerous task, which is one of the primary reasons why zeolites are increasingly being used in many reactions, as they are environmentally benign.
Petrochemical and Detergent Manufacturing
Both alkalylation and alcylation processes produce chemicals used in the manufacture of detergents and ethylbenzene. Since aluminum chloride is also used for the isometrization and reforming of hydrocarbons, and helps in the polymerization of hydrocarbons with lighter molecular weight, the compound is commonly used in the petrochemical sector. The ethylbenzene produced through is further utilized in the production of polystyrene and styrene.
Organic Chemical Production
Aluminum chloride is also an extremely important compound used in organic chemical reactions. It is used to insert aldehyde groups in aromatic system rings. A common process used for this is the Gattermann-Koch reaction. Apart from aluminum chloride, other components of the reaction include carbon monoxide, copper chloride as a co-catalyst, and hydrogen chloride. The compound is a catalyst in the “ene –reaction” used to make polystyrene and other products.
Aluminum Chloride Used in Rubber and Miscellaneous Industries
Aluminum chloride also has wide scale applications in metallurgy. It is combined with aluminum in the presence of a catalyst, arene, to synthesize metal complexes using a process called Fisher-Hafner synthesis. Metal halides are the primary components of this reaction. Apart from this, the compound is also used as a flux and in the electrolytic production of aluminum melting. It is important in manufacturing titanium dioxide and butyl rubber.
Hydrated Aluminum Chloride
The hexahydrate form of aluminum chloride has fewer applications; however, it is a common component in many cosmetic products and toiletries. Hydrated aluminum chloride is often used in low concentrations in most antiperspirants. Prescription products used to control hyperhidrosis have a higher concentration of the compound. There have also been clinical trials to understand the impact of aluminum chloride used in anti-acne preparations.
Despite its extensive use in metallurgical, chemical and cosmetic sectors, pigment industries are the largest consumers of aluminum chloride. The pesticide and pharmaceutical sectors come in a close second and third followed by fine chemicals and aromatic products. Other industries merely consume 4% of the total aluminum chloride production.