The Ford Meter Box Company, Inc.

Gerber Plumbing Fixtures Corp.

Edward L Cote

Andrew Wenzel

Lance E Agness

Michael W Regelbrugge

George V Richey

Lane D Tickanen

Brass articles having leachable lead are contacted with an aqueous caustic solution that contains a chelating agent. A brass article can optionally be post-treated by contacting it with an aqueous solution containing anazole.

Method for treating brass

Brass articles having leachable lead are contacted with an aqueous caustic solution having a pH of about 10 to about 14 that contains a chelating agent. During contact, the brass articles can be sonicated. The brass articles can be optionally pretreated by contacting them with an aqueous solution containing an organic carboxylic acid and an inorganic per-salt. The brass article can optionally further be post treated by contacting them with an aqueous solution containing thiourea.

Brass articles having leachable lead are contacted with an aqueous caustic solution having a pH of about 10 to about 14 that contains a chelating agent. During contact, the brass articles can be sonicated. The brass articles can be optionally pretreated by contacting them with an aqueous solution containing an organic carboxylic acid and an inorganic per-salt. The brass article can optionally further be post treated by contacting them with an aqueous solution containing sodium persulfate.

A process for the treatment of brass components to reduce leachable lead therefrom when the component is exposed to water in which the brass component is first treated with an aqueous caustic solution to remove some of the leachable lead therefrom. Thereafter, the brass component is leached to remove excess caustic and then contacted with a water soluble carboxylic acid to remove most of the remaining leachable lead. It has been found that the efficiency of the process can be significantly enhanced through the use of ultrasonic agitation to ensure intimate contact between the treating solutions and the brass component. In the practice of the invention, the amount of lead removed is sufficient to meet the most stringent regulatory requirements for water quality.

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Novi, MI, United States of America

Edward L Cote