Process for Berlin blue release from waste formed as a result of wine stock demetallization with potassium ferrocyanide(II)

摘要

The invention relates to a process for Berlin blue release from waste formed as a result of wine stock demetallization with potassium ferrocyanide(II) and may be used in the wine industry, in the production of juices and in the tartaric acid production technology.The process includes the 2…4 time dilution of waste with water, introduction of the sodium chloride and the surface-active agent in the following component ratio, in g/l:treatment thereof into an electroflotation device with graphite anode and point cathode with the cathode current density of 1…5 A/dm2, with subsequent separation of the precipitate from the aqueous suspension and its purification by filtration and recrystallization of the Berlin blue.At the same time, as surface-active agent is used the sodic salt of the higher fatty acids, and the recrystallization of the Berlin blue from the precipitate is carried out by treatment of sodium hydroxide up to its change-over into water-soluble state, filtration and separation in acid solution of the ferric sulphate(III).The result consists in increasing the efficiency of cyanide extraction from waste, as well as in reducing the labor intensiveness of the process.