“Good Scale”–“Bad Scale”: How Metal–Phosphonate Materials Contribute to Corrosion Inhibition

Fouling is a well-recognized problem in industrial water streams [1]. In particular, fouling based on mineral scale deposits occurs quite frequently in supersaturated waters [2]. Crystallization of sparingly soluble salts takes place when the solubility product of a certain salt is exceeded. Attachment of the formed crystals onto a “critical” surface creates a recalcitrant deposit. The latter can be removed either by mechanical [3] or chemical means [4].