Applying pulsed corona discharge in hypersaline droplets

Crystallization of salts in droplets of hypersaline solution placed on a glass slide was monitored and evaluated under controlled conditions of temperature and humidity. Pulsed corona discharge (PCD) was applied over sessil droplets on a glass surface, and its effect in the crystallization is demonstrated for the first time. These results were compared with natural evaporation. Under natural evaporation, crystals are firstly formed on surface, near edges of the drop and grow towards the center, eventually acquiring a pyramidal morphology. Under PCD, a Taylor cone is formed between electrode and droplet surface and then, 4 s after the beginning of the discharge, small crystals were formed on the cone besides a dense crystal film around the discharge incidence point in the droplet. These results are discussed considering existing knowledge about plasma–liquid interaction (PLI) and dynamical of crystal growth. This paper explores an interesting aspect of PLIs, which has both fundamental and practical usefulness, for understanding desalination processes, salt crystallization on water surface and biomedical science for advances in electrosurgical methods. (paper)