Криолит природный и искусственный. Определение содержания кремния. Спектрофотометрический метод с применением восстановленного молибдосиликата
Название (англ.):
Cryolite, natural and artificial; Determination of silica content; Reduced molybdosilicate spectrophotometric method
Описание (англ.):
Specifies methods of test for natural and synthetic materials having a molar ratio sodium fluoride/aluminium trifluoride between 3 and 1,7 approximately. The method is applicable to products the phosphoruspentoxide content of which does not exceed 0,02 % (m/m). The procedure consists in alkaline fusion of a test portion by means of a mixture of sodium carbonate and boric acid. Dissolution of the fused mass in excess nitric acid so that the pH value is between 0,7 and 0,9. Formation of the (Yellow) oxidized molybdosilicate under clearly defined conditions of acidity, temperature, time and concentration of reagents. Selective reduction in the presence of tartaric acid and measurement at a wvelength of about 815 nm.
Дата регистрации:
01.11.76
Дата введения:
01.09.76
Код КГС:
А39;Л19
Код ОКСТУ:
1711;1709;2109
Код ОКС(МКС):
71.060.50
Код ОКП:
1711;1709;2109
Нормативные ссылки:
BS 5050-1974, NEQ*NBN T 03-432-1983, EQV
Ключевые слова:
ALUMINIUM ORES CHEMICAL ANALYSIS CHEMICAL ANALYSIS AND TESTING CRYOLITE DETERMINATION OF CONTENT SILICON DIOXIDE SPECTROPHOTOMETRIC ANALYSIS SPECTROPHOTOMETRY CHEMICAL ANALYSIS AND TESTIN