BigPatents India

The process of the present invention relates to the preferential iron precipitation from leach liquor by adjustment of pH, in the presence of microorganism. In this process for biological abatement of iron from hydrometallurgical leach liquor, the essential steps or the process are simultaneous iron oxidation and iron precipitation in the presence of Thiobacillus ferrooxidans at a higher pH in the range of 2.5 to 2.9 The oxidation of ferrous sulfate to ferric sulfate followed by simultaneous precipitation of the later to crystalline jarosite compounds in the presence of Thiobacillus ferroodixidans is effect5ed at a higher pH in the range of 2.5 to 2.9. The process is crried out at an ambient temperature and iron precipitated as crystalline jarosite compounds. The precipitte is separated by known methods from the leach liquor. Thus iron free leach liquor is obtained which can be treated by known methods for the recovery of other useful metal ions.