Extn. of uranium from phosphate ore - by reaction with oxalic acid and subsequent treatment with alkali

摘要

The ore is first reacted with a suitable organic acid, pref. oxalic acid and then treated in a known way with soda or sodium hydrogen carbonate as alkali, and the U is extracted from the resulting soln. The ore may also be heated with an aq. soln. of a strong organic acid or damp ore can be heated with the acid. The process replaces sulphuric acid extn. and is thus more economic. Oxalic acid is consumed in the process, avoiding a reclamation process. The oxalic acid is made from cO and NaOH at 380 degrees C and moderate press. to form Na oxalate, which is reacted with HCl to form oxalic acid and NaCl. The CO may be made from a suitably sited source of C, such as coal or peat. The prim. and sec. phosphate arising from the extn. can be converted to neutral phosphate by reaction with CaCO3 or by a heat treatment and this may be used as a fertiliser.