Complexing capacity of electroplating rinsing baths—a twist to the resolution of two ligand families of similar strength

Abstract

Background: The presence of ligands affects metal behavior when removing metals from wastewaters. So far, most of the attention has been paid to strong ligands; however, experimental observations indicate that also weaker complexing agents may play a key role in the availability of metals in waters and in the success of the treatment to be applied. In particular, we have analyzed wastewaters of an electroplating facility during an 8-h workday. Total metal content (copper, zinc, cadmium, and lead) was determined; ligands were characterized by concentration (Lt) and strength (conditional stability constant, K'f). This work focuses on ligands of moderate strength which, as far as we know, have been overlooked in the literature.