Ammonium persulphate, or APS, is an inorganic compound that comes in the family of persulphates. It has a white crystalline powder appearance, but has a mild and unpleasant odor. It is a strong oxidizing agent and is relatively soluble in water, even more than the related potassium salt. Since it is a strong oxidizing agent, it is best used as ingredient in cleaning and bleaching agent. It does not burn readily, but may cause spontaneous ignition of organic materials.
Hugh Marshall first described that ammonium persulphate can be prepared by electrolysis of a cold concentrated solution of either ammonium sulphate or ammonium bisulphate in sulfuric acid at a high current density.
The Main Uses of Ammonium Persulphate are:
- It is mainly used as radical initiators in the polymerization of certain alkenes. Some polymers prepared using persulfates include styrene-butadiene rubber and polytetrafluoroethylene.
- It can be used together with tetramethylethylenediamine to catalyze the polymerization of acrylamide in making a polyacrylamide gel, hence being important for SDS-PAGE and western blot.
- It is used to etch copper on printed circuit boards as an alternative to ferric chloride solution.
- It serves as a standard ingredient in hair bleach.