P-Mg3P2-PH3-P2O5-K3PO4-Ca3(PO4)2
3Mg+2P=Mg3P2 Mg3P2+3H2=2PH3+3Mg 2PH3+4O2=P2O5+3H2O P2O5+3K2O=2K3PO4 2K3PO4+3CaCl2=6KCl+Ca3(PO4)2