Processes for the anaerobic bioconverison of syngas to oxygenated organic compound with in situ protection from hydrogen cyanide

摘要

Processes are disclosed for the anaerobic bioconversion of syngas to oxygenated organic compound that use an in situ method for protecting the microorganisms from hydrogen cyanide contained in the syngas that passes to the fermentation broth. The fermentation broth is maintained at a pH of between about 4 and 6, and dissolved metal cation of one or more of iron, cobalt, nickel and zinc is provided to the fermentation broth in an amount sufficient to form, under the conditions of the fermentation broth, a substantially insoluble metal complex with the metal cation and cyanide anion. The rate of formation of the insoluble complex is sufficiently high that that the amount of cyanide that is taken up by microorganisms does not result in an undue adverse effect on the population of microorganisms.