The procedure is based on the catalytic conversion of nitrogen present in a test portion to ammonia by heating in concentrated sulphuric acid solution. Distillation and absorption of the ammonia in an excess of standard volumetric sulphuric acid solution and back-titration with standard volumetric sodium hydroxide solution in the presence of an indicator. - Replaces ISO Recommendation R 1592-1970.
Текущий статус : WithdrawnДата публикации : 1977-11
Версия : 1