Process for preparing usable products from an impure ferric sulfate solution
AssigneeKemira Chemicals, Inc.
InventorsSimo Jokinen, Stefan Jäfverström, Timo Kenakkala
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AssigneeKemira Chemicals, Inc.
InventorsSimo Jokinen, Stefan Jäfverström, Timo Kenakkala
Estimating the term…
The invention relates to a process for preparing a usable product, in particular a water treatment solution which contains ferric iron, from an impure ferric sulfate solution which contains as an impurity at least one other metal, the process comprising a first precipitation step in which a base is added to the said impure ferric sulfate solution in order to raise the pH to approx. 2-5, preferably approx. 3-4, whereupon ferric hydroxide precipitates; following the first precipitation step, a second precipitation step in which there are added to the solution an oxidant and a base to raise the pH to approx. 6-10, preferably approx. 8-9, whereupon the said impurity metal precipitates; and one or more separation steps to separate from the sulfate solution the solids precipitated in the first and the second precipitation steps; as well as possibly an additional step in which the said separated solids, or a portion thereof, are treated further in order to form a usable product.
A process for preparing a usable product containing ferric iron from an impure ferric sulfate solution, the process comprising:
Dependencies are inferred from the claim text.