Synthesis of amino sulfonic acid

1. A lot of production methods amino sulfonic acid, sulfur dioxide and hydroxylamine or acetone oxime as raw materials of the hydroxylamine method, sulfurous acid ammoniation method or sulfate and ammonia as raw material, urea and chlorosulfonic acid as the raw material of chlorosulfonation method, with fuming sulfuric acid and urea as raw materials of fuming sulfuric acid, urea, sulfur trioxide and sulfuric acid as raw materials of sulfuric acid and fuming sulfuric acid method (also known as liquid phase method and liquid ammonia gasification and sulfur trioxide in the gas phase reaction under the condition of gas phase method, etc. Industrial significance of technology at home and abroad for the fuming sulfuric acid method and sulphur trioxide two ammoniation method and the direct synthesis of ammonia. By urea and fuming sulfuric acid in the 40-70 ℃ under the sulfonated raw produce amino sulfonic acid, then adding water to crystalline amino sulfonic acid was finished. Raw material consumption quota: urea, 2000 kg/t fuming sulfuric acid, 1500 kg/t.
2. Its synthetic methods mainly have two phase method and liquid phase method. Gas phase method of harsh operating conditions, equipment, material requirement is high. By-products, and amino acids easy adhesion on the inner wall of the reactor should always clean up. The production cost is high. The advantage is the product of high purity. Manufacturers using liquid phase method.
3. To add too much fuming sulfuric acid in the reaction kettle, mixing and cooling to 20 ~ 40 ℃, began to join proportionally mixed sulfuric acid and urea. After the feeding, stir in about 20 ℃ 8 h. Heats up to 70 ~ 90 ℃, steamed out of sulfur trioxide, cooling crystallization. After solid-liquid share thick amino sulfonic acid, water recrystallization, high purity products sulfamic acid dehydration.
4. Sulfamic acid is a strong SO3 Lewis acid and strong alkali Lewis NH3 adduct, making a small amount of high purity requirements of amino sulfonic acid, can be in the absence of water completely, with highly purified SO3 directly react with ammonia. If the amount is large urea and fuming sulfuric acid reaction to making available. Put round bottom flask with a mechanical stirring device in flow water, to add 560 g 100% sulfuric acid, several times under strong stirring to 100 g of urea (about 45 min) slowly added to the sulfuric acid, be careful not to make the temperature more than 40 ℃. And then to add 309 g fuming sulfuric acid (containing 65% free SO3), and placed in 42 ~ 45 ℃ temperature 16 h. Glass sand core filter funnel reaction mixture, with pure sulfuric acid washing, first with 50% sulfuric acid washing, finally with cold methanol washing.
5. 20% of the heating to 30 ℃, fuming sulfuric acid and urea in 60 ~ 65 ℃, temperature control and heat preservation after 3 h, then heating to 80 ~ 85 ℃, heat preservation, 2 h after the reaction, cooling to 5 ℃, filtering, the crystallization of the centrifugal dry, after washing with 5% ethanol, drain with distilled water after recrystallization refined, amino sulfonic acid is tasted.http://www.sulfamic-acid.com/