Aluminum sulfide is a white, insoluble chemical compound. It is moderately water and acid soluble and may be present in some organometallic forms. Like most metal sulfides, it is moderately toxic and corrosive, forming aluminum hydroxide and hydrogen sulfide upon exposure to moist air.
It is produced by the reaction of aluminum metal with sulfur, yielding a yellowish-gray solid with the odor of hydrogen sulfide. It is also known as dialuminium trisulfide. It decomposes when exposed to moisture, hydrolyzing to hydrated aluminum oxides and hydroxides. Exposure to this substance can cause severe skin and eye irritation, as well as breathing problems.
The soluble form of this chemical, called alum, is used as an astringent. It is a key ingredient in styptic pencils, which are used to stop bleeding from minor cuts and abrasions. It can be purchased over the counter and is generally recognized as safe when used properly.
This compound is ionic, meaning that when it bonds with another element it transfers electrons. It reacts with a wide variety of substances including acids, bases, and organic molecules. It is an excellent conductor of heat and electricity and is much lighter than copper in relation to its weight. It is used in power lines, computer and cellphone frames, foils, beer kegs, kitchen utensils, ships, airplane parts, and other products.
It is also used as a stabilizer for vaccines. It prevents the proteins in the vaccine from precipitating or sticking to the walls of the container during storage. It also stimulates the immune system by causing the release of uric acid, which attracts certain types of monocytes that differentiate into dendritic cells and initiate an antigen response.