Phosphogypsum

As phosphogypsum (also phosphogypsum ) is defined as the in the phosphate industry in large amounts obtained as a by-product gypsum. Due to impurities in the starting products of this gypsum contains radioactive and toxic ingredients, such as traces of uranium or radium. Only about 2% of the phosphorus gypsum can be used because it can economically because of the expense of cleaning not compete with other types of plaster, the rest is stored mostly in the open air and poses a potential environmental and water burden or hazard dar.

Phosphogypsum is formed by reaction of fluorine apatite ( Ca5 (PO4) 3F) with sulfuric acid ( H2SO4) in the production of phosphoric acid ( H3PO4) in accordance with the reaction:

Formed in the reaction of gaseous hydrogen fluoride ( HF) escapes and is collected separately for further use. The phosphate present in uranium compounds are present after the reaction in the phosphoric acid present in dissolved form and can be obtained therefrom as uranium (V, VI ) oxide ( U3O8 ). Traces of radium can be separated from the produced phosphogypsum with special cleaning procedures.