Method for preparing battery-grade iron phosphate from wet-process phosphoric acid

The invention discloses a method for preparing battery-grade iron phosphate from wet-process phosphoric acid, which comprises the following steps: carrying out pH regulation, precipitation reaction and filtration on wet-process phosphoric acid to obtain a preliminarily purified ammonium phosphate solution; adding a depotassium agent into the obtained ammonium phosphate solution, and reacting to obtain a phosphorus-containing clear solution; adding a fluorine removal agent into the obtained phosphorus-containing clear liquid, and reacting to obtain the phosphorus-containing clear liquid; adjusting the pH value of the obtained phosphorus-containing clear liquid, and reacting to obtain a refined ammonium phosphate solution; dropwise adding the obtained ammonium phosphate solution into a ferrous sulfate solution, and introducing an oxidizing agent to fully react to obtain battery-grade iron phosphate dihydrate; and finally, calcining, and removing crystal water to obtain the battery-grade anhydrous iron phosphate