Urea

Urea, also known as carbamide, is a safe, useful compound with a significant history. It is a naturally occurring molecule that is produced by protein metabolism and found abundantly in mammalian urine. he demonstrated that a biomolecule, urea, can be synthesized from a nonbiological starting material. prepared the inorganic compound ammonium cyanate in the lab, then heated it, causing it to isomerize to urea. Now known as the synthesis, the reaction helped to disprove the concept of vitalism, which held that organic molecules can be made only by living organisms.2 In a reaction similar to the synthesis, ammonium carbamate can be converted to urea and water. This is the basis of the process that has been used to produce urea industrially for almost a century. Ammonia and carbon dioxide (CO2) react exothermically to produce the carbamate salt, which is then heated to form urea. The heat produced in the first reaction drives the second. Typically, ammonia and urea are manufactured in the same plant so that some of the carbon dioxide byproduct from ammonia production can be used to make urea. Global urea production capacity is 220 million t/year. Why is urea produced in such large quantities? The answer is that, other than ammonia, urea has the highest nitrogen content of all industrial chemicals and is in high demand as a fertilizer. In the soil, it decomposes back to ammonia (actually ammonium ion) and carbon dioxide. Nitrogen-fixing bacteria oxidize ammonium to nitrate, which is readily taken up by the roots of crops. In addition to its high nitrogen content, urea is particularly useful because it can be applied as a solid in pellet form; and its unusually high solubility in water allows it to be incorporated into solutions with other plant nutrients.