Презентация на тему Получение натрия сульфата

основанием NaOH и сильной кислотой H2SO4, ее раствор имеет

показатель рН, близкий к нейтральному. То есть индикаторы типа лакмуса и фенолфталеина в растворе этой соли не меняют цвет.

acid. When anhydrous, it is a white crystalline solid

of formula Na2SO4 known as the mineral thenardite; the decahydrate Na2SO4·10H2O is found naturally as the mineral mirabilite, and in processed form has been known as Glauber's salt or, historically, sal mirabilis since the 17th century.
Another solid is the heptahydrate, which transforms to mirabilite when cooled. With an annual production of 6 million tonnes, it is a major commodity chemical product.

натрия при высоких температурах (порядка 550 градусов). Реакция идет

следующим образом:
2NaCl + H2SO4 = Na2SO4 + 2HCl
About one third of the world's sodium sulfate is produced as by-product of other processes in chemical industry. Most of this production is chemically inherent to the primary process, and only marginally economical. By effort of the industry, therefore, sodium sulfate production as by-product is declining.
The most important chemical sodium sulfate production is during hydrochloric acid production, either from sodium chloride (salt) and sulfuric acid, in the Mannheim process, or from sulfur dioxide in the Hargreaves process.The resulting sodium sulfate from these processes are known as salt cake.
Mannheim: 2 NaCl + H2SO4 → 2 HCl + Na2SO4
Hargreaves: 4 NaCl + 2 SO2 + O2 + 2 H2O → 4 HCl + 2 Na2SO4

from the reaction between sodium bicarbonate and magnesium sulfate.
2NaHCO3

+ MgSO4 → Na2SO4 + Mg(OH)2 + 2CO2
Formerly, sodium sulfate was also a by-product of the manufacture of sodium dichromate, where sulfuric acid is added to sodium chromate solution forming sodium dichromate, or subsequently chromic acid. Alternatively, sodium sulfate is or was formed in the production of lithium carbonate, chelating agents, resorcinol, ascorbic acid, silica pigments, nitric acid, and phenol.
Bulk sodium sulfate is usually purified via the decahydrate form, since the anhydrous form tends to attract iron compounds and organic compounds. The anhydrous form is easily produced from the hydrated form by gentle warming.

серной кислотой на соду кальцинированную (натрий углекислый). Реакция идет

до конца, поскольку в результате образуется слабая угольная кислота, которая сразу же разлагается на воду и углекислый газ:
H2SO4 + Na2CO3 = Na2SO4 + H2CO3
H2CO3 = H2O + CO2