On extraction of hafnium in the form of rhodanide from sulfuric-acid solutions

Some ways for improving the method of recovering hafnium from sulphate solutions of zirconium production have been studied. It is shown that return sulphuric acid solutions can be used for leaching calcium zirconate. Extraction characteristics are not impaired by reducing the extractant stream. Precipitation of hydroxide from the rafinates of counter-current extraction leads to destruction of the non-extractable forms of zirconium (hafnium) and allows an increase in the recovery of hafnium