SUBJECTS ferrocyanide

K Salt. A yellow cryst solid, prepd by the action of basic K salts on TeNMe in the presence of reducing agents (see also above under TNMe). Some which have been used are K methoxide in me ale (this proc is subject to dangerous expins) (Ref 8) K cyanide in me ale (Ref 23) a satd aq soln of K ferrocyanide (Ref 9) or K nitrite in w, yield 80% (Ref 38). It has also been prepd by the action of K nitrite on dibromodinitromethane (Ref 13). Its expln temp is 97-98° (Ref 3) and its impactg sensy, using a noisemeter to detect explns, was found to... 

If an alkali salt of a sulphonic acid is subjected to dry distillation with potassium cyanide or potassium ferrocyanide a nitrile is obtained, e.g. 

The hematite with adsorbed Co-57 or Sb-119 along with the solution was subjected to emission Mossbauer measurement at 24 1°C with the experimental setup shown in Figure 2. The absorber, Fe-57-enriched potassium ferrocyanide (0.5 mg Fe-57/cm2) or barium stannate (0.9 mg Sn-119/cm2), was driven by a Hanger 700-series Mossbauer spectrometer connected to a Tracor-Northern TN-7200 multi-channel analyzer. The Mosssbauer gamma-rays of Co-57 and Sb-119 were detected respectively with a Kr(+3% carbon dioxide)-filled proportional counter and with a 2 mm-thick Nal(Tl) scintillation counter through 65 pm-thick Pd critical absorber for Sn K X-rays. The integral errors in the relative velocity were estimated to be of the order of 0.05 mm/s by repeated calibration measurements using standard absorbers. 

The practice of assuming an increased valency for nitrogen when ammonia unites with hydrogen chloride, says A. Werner, if consistently carried out, would make antimony tervalent in antimony trichloride, and quinquevalent in SbCl3.KCl, etc. Bivalent iron in ferrous cyanide, FeCy2, would become decivalent in potassium ferrocyanide, K4FeCy6. J. Piccard and J. H. Dardel, and P. Pfeiffer discussed this subject. 

Test for Fe or Cu in effluent to 2 drops effluent on spot plate add 2 drop cone. HCl and 2 drops fresh S% potassium ferrocyanide solution. Blue color indicates Fe . Brown color is Cu . Most spot tests can be performed directly on the resin e.g., a particle of resin containing 2 ppm iron will turn blue when subjected to ferrocyanide tests. 

This process, which was developed and commercialized at the gas works at Hamburg, Germany, and patented by Fischer (1932), utilizes an aqueous solution containing about 20% potassium ferrocyanide and 6% potassium bicarbonate. The solution is subjected to electrolysis, which converts a portion of the ferrocyanide to ferricyanide and an equivalent amount of the bicarbonate to carbonate, releasing at the same time a proportionate volume of hydrogen. The presence of both ferricyanide and carbonate enables the solution to absorb H2S rapidly and to convert it immediately to elemental sulfur. The reactions involved can be expressed by the following equations ... 

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