Preamble:
Glycerol refers to a polyol compound that has been extensively used in food and pharmaceutical industries. They are prevalently found in all triglycerides. They possess hydroxyl groups that account for their hygroscopic properties. Non toxicity, sweet taste, lack of color and odor are such credible features for this chemical compound. These properties have subsequently led to the usage of glycerol as sweeteners and humectants in food industries. They are rampantly used for pharmaceutical formulations.
Natural production:
Animal and plant sources are normally used for the procurement of glycerol compounds wherein these compounds occur in their triglyceride forms. The plant sources entail palm or soybeans. The replacement of petroleum has consequently resulted in the high production rate of biofuel. Glycerol is a byproduct obtained in the production process of biofuel. Hence, the production of glycerol would become relatively higher and six times more than required. The manufacture of glycerol compound would require hydrolysis, saponification or transesterification processes of triglycerides. The acquired glycerol is crude would have to be purified. Hence, they are purified by multi-step distillation processes. Glycerol compounds have high boiling point and hence vacuum could be very helpful in the purification process.
Synthetic production:
Glycerol could be produced from propylene as well by various routes. However, the production of glycerol from propylene is not so cost efficient. The epichlorohydrin process is the most pivotal amongst various routes. The market for synthetic glycerol production has declined to a great extent due to the release of glycerol compounds as waste products from biodiesel production. Glycerol compounds are transformed to epichlorohydrin and acrolein compounds that are synthetic precursors for the manufacture of various other compounds.
Applications:
Food industries:
The preservation of food requires glycerol compounds. They are combined with water to preserve certain kinds of plant leaves. They are also employed as solvents, sweeteners and humectants in food industries. They are effective thickening agents being used in liqueurs. They are commercially manufactured and are used as fillers in low-fat food items like cookies. Glycerol has been categorized as a carbohydrate by the Academy of Nutrition of dietetics.
Prominence in various other industries:
They are extensively used in personal care and pharmaceutical applications. They are found in water-based personal lubricants, skin care products, allergen immunotherapies, mouthwashes, cough syrups, expectorants, shaving cream, elixirs, soaps, tooth paste and hair care products. They are also employed as tablet holding agents. People with sensitive skin prefer to use glycerol soaps that contain glycerin. They could also be used through oral consumption to treat inordinately elevated eye pressure conditions. Furthermore, they are used as solvents in herbal extract processes as an alternative to ethanol. They are also used as chemical intermediates, antifreeze and in the production of aerosol that delivers nicotine in an electronic cigarette.