What is Alum?
Alum is a chemical compound commonly used to refer to hydrated aluminum double sulfate salt with the general formula XAl(SO4)2·12H2O, where X is a monovalent cation such as potassium or ammonium. Other types of alum are named after their monovalent ion, such as sodium alum and ammonium alum. Alum has several common chemical properties, including water solubility, a sweet taste, and the ability to react like an acid, turning blue litmus red. Alum is used in a variety of applications, including as a food additive for pickling and canning, in cosmetics for its astringent and antibacterial properties, and in water treatment to remove impurities.
Types of Alum
There are several types of alum, including:
- Potassium alum or potassium alum (KAl(SO4)2·12H2O)
- Alum or sodium alum (NaAl(SO4)2·12H2O)
- Ammonium alum (NH4Al(SO4)2·12H2O)
- Chromium alum or chromium alum (KCr(SO4)2·12H2O)
- Alum selenate (NaAl(SeO4)2·12H2O)
- Aluminum sulfate (Al2(SO4)3)
These types of alum have different formulas and chemical properties and are used in many different applications such as water treatment, food additives and cosmetics. Potassium alum is the most common type of alum and is also known as fitkari.
Alum applications
Alum has many applications in different fields. Some common uses of alum are:
Water treatment
Alum is used in water treatment as a coagulant to remove impurities from contaminated water. It acts as a coagulant in the coagulation-flocculation process of contaminated water, improving the treatment process's ability to remove unwanted particles.
Food industry
Alum is used during cooking and pickling as a preservative and pickling agent to maintain the crisp texture of the pickles. It is also used as an acidifying agent in cooking
Cosmetics
Alum is used in cosmetics for its astringent and antibacterial properties. It can temporarily shrink pore size and tighten skin. It is also bacteriostatic, meaning it prevents the growth of bacteria, making it useful as a preservative .
Medical Application
Alum has anti-inflammatory properties and is often used during mouth washing to reduce inflammation and sore gums. It may also be useful in treating bleeding gums, gingivitis, pus, tonsillitis, pharyngitis, hemorrhoids, vaginitis, leukemia, gonorrhea, kidney and bladder abscesses, kidney and bladder stones. pharyngitis, conjunctivitis, ear abscesses, dandruff, burns, breast enlargement, stomatitis, dementia, asthma and bleeding.
Other applications
Alum is used in the tanning process, as a mordant in dyeing, and in vaccine production. It can also be used as a coagulant in water filtration plants to absorb suspended particles in water.
