| 摘要 |
FIELD: chemistry. ^ SUBSTANCE: method of obtaining sodium hydroxide in solid state involves evaporation of aqueous NaOH solution which contains sodium chlorate and addition of reducing agents - sucrose and sodium thiosulphate. The process is carried out in a nickel reactor with stepped increase in temperature from 70C to 340C. Aqueous sodium thiosulphate, which contains 60-75% sodium thiosulphate of the stoichiometric amount relative sodium chlorate contained in the initial solution, is first added to the evaporation zone at temperature of 70-100 C. Aqueous sucrose solution, which contains 20-35% sucrose of the stoichiometric amount relative sodium chlorate contained in the initial solution, as well as a corrosion inhibitor - oxyethylidenediphosphonic acid in amount of 0.0003-0.00045% of the obtained sodium hydroxide, are fed to the evaporation zone at temperature of 100-340 C. ^ EFFECT: invention improves quality of the end product and service life of the equipment. ^ 2 tbl, 4 ex |
