Goethite Method Of Zinc Sulfate Leach Solution In Addition To Iron

Compare to jarosite process, goethite process owns many advantages for the removeal of ferric or ferrous ions, such as large crystal, less valuable metal loss, filtration. Ferric or ferrous ions can be effectively moved by adding goethite crystal seeds, therefore, the preparaton of goethite crystal seed is very important.Suitable methods were selected to synthesize goethite, including hydrothermal synthesis, micro-wave synthesis, ultrasonic-wave synthesis, similar-crystal synthesis. Goethite crystal seed is successfully prepared via hydrothermal method in acidic solutions at 80 to 110℃. It was suggested that large amount of goethite seeds could be produced by pseudo-homogeneous nucleation method with integral reaction apparatus to meet the mass demand of industry to remove ferric/ferrous ions from leaching solution in zinc hydrometallurgy.Differential reaction apparatus is firstly used to remove of ferrous/ferric from the leaching solution of zinc in hydrometallurgy by adding goethite crystal seeds. The effects of crystal seed, acidity, neutralizers and ageing were investigated. The experiment shows that the removal ratio of iron ions is over 99.7% in the existance of large amount of crystal seeds, and purified solution contains about 0.0064g/L iron ions when pH is 2.5. Contrarily, the removal ratio of iron ions is only 90% without the addition of crystal seeds and the purified solution contains over 0.0091g/L iron ions when pH is 3.7. The effects of different neutralizers on product was also investigated. It was found that the purity is very high when sodium carbonate solution and serosity prepared by chemical purity zinc oxide was used as neutralizer. At the same time, the product contains plumbojarosite when volatilization kiln zinc oxide was used as the neutralizer. Therefore, roasted product contains zinc ferrite was not a suitable neutralizer in our experiments.