Glycerin (glycerol/glycerin), also known as glycerol, is used widely. It can be used to produce synthetic resins, plastics, paints, nitroglycerin, oil and beeswax, etc. as well as used as emulsifier, softener and plasticizer in pharmacy, perfume, cosmetics, sanitary products and other industries.
Before the mid 20th century, glycerol is the byproduct when using animal and vegetable fats to make soaps, and later it is also produced by propylene in the form of industrial synthesis. In the current biodiesel esterification process, each 10 kg of biodiesel can produce 1 kg of glycerol byproduct. Biodiesel industry has changed the glycerol industrial ecology in the past.