Тезис

The general method is applicable to phosphoric acid not containing polyphosphoric acids and to products having a calcium content equal to or greater than 0.020 % (m/m). In special cases a preliminary hydrolysis of polyphosphoric acids is carried out by prolonged boiling in the presence of hydrochloric acid. Precipitation of calcium as calcium oxalate at pH 4 0.3, filtration of the precipitate, dissolution in hydrochloric acid and re-precipitation under the same operating conditions in order to purify the precipitate. Oxidimetric titration in sulphuric acid solution by means of potassium permanganate. - Cancels and replaces ISO Recommendation R 848-1968.


Общая информация 

  • Текущий статус
     : Отозвано
    Дата публикации
     : 1981-11
  • Версия
     : 1
  • Технический комитет
     : ISO/TC 47 Chemistry
  • ICS
     :
    71.060.30 Acids

Жизненный цикл

Появились вопросы?

Ознакомьтесь с FAQ

Работа с клиентами
+41 22 749 08 88

Часы работы:
Понедельник – пятница: 09:00-12:00, 14:00-17:00 (UTC+1)

  2. Интернет-магазин
  3. Каталог стандартов
  4. ТК
  5. ISO/TC 47
  6. ISO 848:1981