The Surface Modification of Lead Using Electrochemical Potential Sweep Technique

Lead has serious influences on the human body, and lead release from water supply lead pipe into tap water becomes one of the serious problems. The regulations for lead concentration in tap water have gradually become stricter, and will likely be even more stringent in the future.As one of the methods for dealing with the problem of lead water supply pipes prudently, the authors took notice of the electrochemical surface reforming method, and the modification of the lead surface was tried using the repetition technique of the anode-cathode alternate potential sweep. A phase-mixed modified layer, which consists of lead carbonate, lead hydroxide, lead monoxide and lead dioxide, was formed by electrolysis using alkaline electrolyte including carbonate ions. With this modified surface layer, it was possible to suppress the elution amount of lead to about 25 % of that of untreated lead.