Probing the Inhibitory Mechanism of Calcite Precipitation by Organic Phosphonates in Industrial Water Cooling System

Abstract

Available experimental data on stability constants of proton and metal complexes for 10 phosphonic acids {[}methylphosphonic acid, 1-hydroxyethane-1,1-diylbisphosphonic acid, dichloromethylenebisphosphonic acid, amino-methanephosphonic acid, N-(phosphonomethyl)glycine, imino-N,N-bis(methylenephosphonic acid), N-methylamino-N,N-bis(methylenephosphonic acid), nitrilotris(methylenephosphonic acid), 1,2-diaminoethane-N,N,N',N'-tetrakis(methylenephosphonic acid), and diethylenetriamine-N,N,N',N{''},N{''}-pentakis(methylenephosphonic acid)], published in 1950-1997, have been critically evaluated. For the latter phosphonate, all the data are rejected, as well as protonation constants {[}HL]/{[}H]{[}L] for three other ligands. Higher-quality data are selected and presented as ``Recommended{''} and ``Provisional{''}.