dodecasodium [ethane-1,2-diylbis[[(phosphonatomethyl)imino]ethane-2,1-diylnitrilobis(methylene)]]tetrakisphosphonate;[1,2-Ethanediylbis[[[[di(sodiooxy)phosphinyl]methyl]imino]-2,1-ethanediylnitrilobis(methylene)]]tetrakis(phosphonic acid disodium) salt