Urea Production Method

In industry, liquid ammonia and carbon dioxide are used as raw materials to directly synthesize urea under high temperature and high pressure conditions. The chemical reaction is as follows: 2NH3+CO2→NH2COONH4→CO(NH2)2+H2O. Urea is easily soluble in water and can be dissolved in 100ml of water at 20℃. Dissolved 105 grams, the aqueous solution showed a neutral reaction.

There are two types of urea products. Crystalline urea is white needle-like or prismatic crystals with strong hygroscopicity. Granular urea is a translucent particle with a particle size of 1 to 2 mm, which has a smooth appearance and improved hygroscopicity.

At 20°C, the critical moisture absorption point is 80% relative humidity, but at 30°C, the critical moisture absorption point drops to 72.5%. Therefore, urea should not be stored in the humid climate in midsummer. Adding hydrophobic substances such as paraffin wax to the production of urea greatly reduces its hygroscopicity.