Method for reducing the content of heavy metals, including Cadmium compounds in the raw phosphate.

摘要

Method for reducing the content of heavy metals, including Cadmium compounds in the raw phosphate.Gross Mixed phosphate, nitric acid to 30 - 70 and CALCIUM NITRATE solution with a concentration of 10 - 50 weight and adjusts the PH of the mixture to 0.2 - 3 by using an Acid Solution, such as nitric acid, Phosphoric Acid, hydrochloric acid or mixtures thereof, and the proportion of raw phosphate to li Liquids added 0.3 - 3: 1.It separates the phosphate Gross, for example by Filtration, and then performs a Neutralization of Sodium Hydroxide, for example, the solution containing Heavy Metals, these Metals are precipitated as sulphides adding Hydrogen sulfide, proceeded a Body of a Neutralization, or extracted Heavy Metals with an agent, extractionAs a ditiofosfinico acid. In all these cases the CALCIUM NITRATE is returned at the beginning of the process.