Cyanides oxidation

Cyanide [57-12-5] Cyanide detoxification Cyanide exchange Cyanide iron blue Cyanide oxidation Cyanides... 

Cyanides are dangerously toxic materials that can cause instantaneous death. They occur in a number of industrial situations but are commonly associated with plating operations, and sludges and baths from such sources. Cyanide is extremely soluble and many cyanide compounds, when mixed with acid, release deadly hydrogen cyanide gas. Cyanide is sometimes formed during the combustion of various nitrile, cyanohydrin, and methacrylate compounds. Cyanides (CN ) are commonly treated by chlorine oxidation to the less toxic cyanate (CNO ) form, then acid hydrolyzed to COj and N. Obviously, care should be taken that the cyanide oxidation is complete prior to acid hydrolysis of the cyanate. 

C41 Cyanide Oxidation -- Alkaline Chlorination R09 Reuse as Fuel - Other... 

C42 Cyanide Oxidation -- Electrochemical R11 Solvents/Organics Recovery - Batch Still... 

Cyanide oxidation consists of a reaction with sodium hypochlorite under alkaline conditions in either a batch or continuous system. A complete system includes reactors, sensors, controls, mixers, and... 

Ozonation treatment can be used to oxidize cyanide, thereby reducing the concentration of cyanide in wastewater. Ozone, with an electrode potential of +1.24 V in alkaline solutions, is one of the most powerful oxidizing agents known. Cyanide oxidation with ozone is a two-step reaction similar to alkaline chlorination.22 Cyanide is oxidized to cyanate, with ozone reduced to oxygen as per the following equation ... 

The reaction time for complete cyanide oxidation is rapid in a reactor system with 10-30 min retention times being typical. The second-stage reaction is much slower than the first-stage reaction. The reaction is typically carried out in the pH range of 10-12 where the reaction rate is relatively constant. Temperature does not influence the reaction rate significantly. 

Acid hydrolysis of cyanates is still commonly used, following a first-stage cyanide oxidation process. At pH 2 the reaction proceeds rapidly, while at pH 7 cyanate may remain stable for weeks.24 This treatment process requires specially designed reactors to assure that HCN is properly vented and controlled. The hydrolysis mechanisms are as follows22 ... 

Option 1 Emulsion breaking and oil separation by skimming, cyanide oxidation, chromium reduction, chemical precipitation and sedimentation, and sludge drying beds. 

N12.84% yel ndls (ale), mp 18i subl. Prepd by hitrating the parent, heating ethyliodide with. sodium -6Tnitro-2-quinolonate, or by the potassium ferri cyanide oxidation as with the 5-nitro compd... 

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