(Ethylenebis(nitrilobis(methylene)))tetrakisphosphonic acid, potassium salt 1429-50-1 34274-30-1 Dequest 2044 EINECS 251-910-1 Phosphonic acid, (1,2-ethanediylbis(nitrilobis(methylene)))tetrakis-, potassium salt Phosphonic acid, (ethylenebis(nitrilodimethylene))tetra-, potassium salt