Method for reducing magnesium and aluminum impurities in wet-process phosphoric acid

The invention discloses a method for reducing magnesium and aluminum impurities in wet-process phosphoric acid. The method comprises the following steps: adding an ammonium fluoride-containing compound into wet-process phosphoric acid, wherein the addition mount of the ammonium fluoride-containing compound is 0.5-5 percent of the mass of wet-process phosphoric acid, the aging temperature is 30-80 DEG C, and the aging time is 5-48 hours; performing free settling, wherein the supernatant liquid is purified wet-process phosphoric acid with low magnesium and aluminum content. The sediment obtained by the method is large in particle and easy to settle, and a removal rate of magnesium and aluminum impurity ions can be 5-40 percent. The method is easy to operate, low in treatment cost and easy for realization of industrial production and has high industrialization popularization value.