SULFAMIC ACID PRODUCTION PROCESS

FIELD: industrial organic synthesis. ^ SUBSTANCE: process comprises oleum-sulfurization of urea, filtration of underluted sulfurization mixture, recrystallization of crude sulfamic acid paste from recycling mother liquor preheated to temperature not higher than 75oC, wherein concentration of sulfuric acid 19-22% is maintained. Weight ratio of sulfamic acid paste to recrystallization liquid is 1:(6-8).Yield of sulfamic acid (calculated as urea) is 83-85%. Filtrate remaining after isolation of sulfamic acid paste from sulfurization mixture represents about 96% sulfuric acid at most 1% of sulfamic acid and can be used in related production fields. ^ EFFECT: simplified technology, reduced sulfuric acid consumption, and improved yield and quality of product with minimum equipment units and low power consumption. ^ 2 cl, 1 dwg, 1 tbl, 5 ex