Determination of a typical additive in zinc electroplating baths

•Determining additives in zinc electroplating baths is critical for process management.•The quantification of a commercial additive based on carbonyl compounds is presented.•Signal generation by formation of MnO2 nanoparticles and pH dependence are analyzed.•It is viable to apply this method to direct measurements in electroplating processes.

Determining commercial additives contained in zinc electroplating baths is critical for quality control and process management in order to obtain better results in zinc coatings, monitor the use of chemicals and establish safe forms of treatment and reuse of wastewater. In this work, the conditions for the quantification by oxidation with potassium permanganate of a commercial brightener mainly composed of chlorobenzaldehyde, were optimized. The signal generation consisted in the formation of MnO2 nanoparticles with a characteristic surface plasmon resonance band (SPRB) at around 400 nm. The results showed that it is viable to apply this method to direct measurements of brightener in electroplating processes.