Urea, also known as Carbon amide (carbamide), is a white crystal. One of the simplest organic compounds. Two amide of carbonic acid, molecular formula is H2NCONH2 (Co (NH2) 2). The main nitrogen-containing end product of protein catabolism in mammals and some fishes. is also the highest nitrogen content of nitrogen. As a neutral fertilizer, urea is suitable for various soils and plants. It is easy to save, easy to use, small damage to the soil, is the current use of a large amount of chemical nitrogen. Ammonia and carbon dioxide are used in industry to synthesize urea under certain conditions.
medical field: The Skin department is to improve the moisture of the skin by using certain medicaments containing urea.
Agricultural field: Urea is a kind of high concentration nitrogenous fertilizer, Urea it is a neutral quick-acting fertilizer, also can be used to produce many kinds of compound fertilizers.
Industrial applications: For steel, stainless steel chemical polishing has a role in the use of metal pickling as a corrosion inhibitor, but also for the preparation of palladium-activated liquid.
Commercial areas: raw materials for special plastics, especially urea-formaldehyde resins, Urea raw materials for some kinds of gum, ingredients for fertilizers and feeds; the advantage of replacing antifreeze salt in the streets is not to corrode metals, to strengthen the smell of cigarettes, to give industrial production of pretzels Brown, some shampoo, detergent ingredients, first aid refrigeration kits, because the reaction of urea and water will be endothermic, automotive urea treatment of diesel engines, engines, Urea thermal power plant exhaust gas, in particular, reduce its nitrogen oxides, rain-absorbent ingredients (salt), Used in the separation of paraffin wax, because urea can form a package, refractories, environmental engine fuel ingredients, whitening the composition of dental products, for chemical fertilizers, dyeing and printing of important adjuvant and other uses
Urea is the first man-made organic matter, widely existed in nature, such as fresh human feces containing urea 0.4%. Urea production accounted for about 40% of the total nitrogen fertilizer production in China, Urea and it is one of the main nitrogen fertilizers after ammonium carbonate.
Urea Molecular formula is Co (NH2) 2, because in human urine contains this substance, so named urea. Urea nitrogenous (n) 46% is the highest nitrogen content in solid nitrogen. Liquid ammonia and carbon dioxide are used as raw materials to synthesize urea directly under high temperature and high pressure, Urea and the chemical reaction is as follows.
2nh3+co2→nh2coonh4→co (NH2) 2+N2O urea soluble in water, in 20 ℃ 100 ml of water soluble 105 grams, aqueous solution is neutral reaction. There are two kinds of urea products. Crystalline urea is white needle-like or prismatic columnar shape, strong hygroscopicity. Granular urea is a translucent particle with a grain size and a millimeter, Urea the appearance is bright and clean, and the hygroscopicity has obvious improvement.
Urea can be applied to both basal and topdressing. Urea is a physiological neutral fertilizer, in the soil does not remain any harmful substances, long-term application has no adverse effects. Urea is the organic nitrogen fertilizer, through the soil urease action, Urea hydrolysis into ammonium carbonate or ammonium bicarbonate, can be used for crop absorption. Therefore, urea should be applied 4-8 days before the fertilizer period of the crop.