4. Biodegradation of organic reagent: cyanide

As we have seen with refractory gold ores, cyanide is used in the mining industry mainly for extracting precious metals and as a flotation agent. It has many other uses, in particular in electroplating and in many organic syntheses (EDTA, cyanoacrylate, amino acids, etc.); it is also found in coke-oven effluents in the company of phenols, pyridine, tar, etc.

Biodegradation of cyanide effluents has been applied to effluents from coking plants, the mining industry and, more recently, the chemical industry.