Method for preparing a neutral sodium pyrophosphate

摘要

process to obtain a neutral sodium pyrophosphate containing at least 85% by weight of tetrasodium diphosphate na4p2o7, is that the concentrated phosphoric acid extraction or thermal, are gradually added, with continuous mixing and rozcieraniu, soda ash or coal sodium n, by mole ratio on / p 1,77 - 2.0 to obtain product of powdery texturethen the resulting mixture kalcynuje in rotary kilns. the subject invention is also neutral sodium pyrophosphate obtained way according to the invention.