The invention discloses a method for all-
component separation, purification and high-value utilization of
ammonium sulfate waste residues, which comprises the following steps: by using low-cost
ammonium fluoride as a
fluorine source, selectively precipitating Mg < 2 + > through one-step fluorination conversion, preparing high-purity MgF2, recovering valuable metals by combining an extraction-reverse extraction process, and preparing a
manganese-
magnesium ferrite material by combining
sol-gel and high-temperature
calcination processes. And recovering an
ammonium sulfate by-product. Compared with an existing high-purity inorganic salt preparation process, high-value utilization of all-component resources in the waste residues is achieved, and the problems that waste residues are difficult to treat, cost is high and the like are solved. The method adopts a one-step fluorination conversion, extraction and reverse extraction process and a
sol-
gel method, and is low in cost, high in
resource utilization rate, non-toxic and harmless. The prepared
magnesium fluoride can be applied to the fields of
optical materials and
electronic ceramics; mnxMg (1-x) Fe2O4 has good
magnetism and photocatalytic performance, so that organic pollutants can be degraded; the recovered
ammonium sulfate can be directly used as a
nitrogen fertilizer raw material, so that multi-component synergistic high-value utilization is realized.