Plus, one brand of kosher salt is more than salt; containing an anti-caking ingredient: yellow
prussiate of soda, also known as sodium ferrocyanide.
After ammonia distillation and dephenolization, Lurgi coal gasification wastewater (LCGW) is still a complex industrial wastewater containing high concentrations of organic matter, ammonia, and
prussiate [4], resulting in unsatisfactory effluent quality after anaerobic-anoxic-oxic (A-A-O) process and sequencing batch reactor (SBR) biological treatment process [5].
Finally, to prove that the substance remaining on the filter was none other than hydrated sesqui-oxide of iron (rust), we have treated some of it with hydrochloric acid; it dissolved completely, and the solution presented a greenish-yellow color; the other part, treated by the
prussiate of potash, produced an abundant precipitate of Prussian blue.