Reference number
ISO 2124:1972
ISO 2124:1972
© ISO 2024
ISO 2124:1972
Sodium and potassium silicates for industrial use — Determination of silica content — Titrimetric method
Edition 1
1972-06
1972-06
Retirada
Resumen
The principle consists in neutralization of the alkalinity of a test portion, previously dissolved, in presence of methyl red as indicator. Addition of sodium fluoride, which reacts with the silicic acid, forming a euaivalent quantity of sodium hydroxide. Addition of a measured volume of standard volumetric hydrochloric acid solution in excess, followed for diluting by ethanol. Filtration of the silicic compound thus obtained, which is insoluble under these conditions. Titration of the excess of hydrochloric acid in the filtrate with standard volumetric sodium hydroxide solution in presence of methyl red as indicator.