????? ????? ??????? ?????????? ?????????? ?????? ???????????? ????????? (APT) ?????? ????? ? ????? ??? ??? ????? ??????? ???????? ????? ? ????? ??? ???????? ?? ??????? ???????? ?? ?????? ??? ??????? ????????? APT ?? ???? ???? ?????? ? ?? ????? ??? ??? ????? ?????:

1. ??? ???????? ??? ????? ?????? ?????? ??? ??????? ???????? (Na ₂ WO ₄ ) ?? ????? ???????? ?????? ??????? ???????? (NaCO ₃ ) ? ?? ????? ??? ??????? ? ??????? ? ????? ????? ????? ?????? ??? ????? ??????? ???????? ????? ? ??????? ??????? ?? ??? ???:
Na₂CO₃+FeWO₄=FeO↓+ Na₂WO₄+CO₂↑
Na₂CO₃+MnWO₄=MnO↓+ Na₂WO₄+CO₂↑;
2. ??? ????? ?????? ????????? (CaCl ₂ ) ??? ????? ????? ??????? ???????? ????? ?????? ??????? ????????? (CaWO ₄ ) ? ??? ??????? ????????? ? ???? ??????? ??? ??? :
Na₂WO₄+ CaCl₂=CaWO₄↓+2NaCl
3. Decompose the artificial scheelite with acid to get tungstic acid, and then add ammonia water to dissolve it and get ammonium tungstate solution, which is the industrial grade ammonium tungstate, the reaction is as follows:
CaWO₄+2HCl=H2WO₄↓+ CaCl₂ H₂WO₄+2NH₄OH=(NH₄)₂WO₄+2H₂O
4. ?????? ?????? ?? ??????? ????????? ?????? ??? APT.