The Boeing Company

David L Crump

David A Huebner

Mark R Woodruff

Warren J Fullen

Lance E Succo

John C Oelund

Methods, systems and apparatuses are disclosed for treating aluminum desmutting solutions by reacting, mixing and filtering an aluminum desmutting solution flow from an aluminum desmutting solution tank and controlling the amount of copper ions in an aluminum desmutting solution tank by directing a portion of the desmutting solution from a desmutting solution tank to a treatment line, reacting a portion of the desmutting solution in the treatment line and recirculating a filtered aluminum desmutting solution to the aluminum desmutting solution tank during active desmutting operation of the aluminum desmutting solution tank.

Methods, systems and apparatuses for copper removal from aluminum desmutting solutions

A system for selectively removing at least one undesirable ion from an acidic solution including a tank receiving the acidic solution, a chiller in fluid communication with the tank, the chiller being configured to reduce a temperature of the acidic solution, and an ion exchanger in fluid communication with the chiller, the ion exchanger including an ion exchange resin that is selective for the undesirable ion.

System and method for selectively removing ions from acidic solutions

An improved method of anodizing an aluminum or aluminum alloy workpiece including the steps of: (a) providing an aqueous anodizing bath consisting essentially by weight of about 3 to 5 percent sulfuric acid, from about 0.5 to 1 percent boric acid, not more than about 5.0 g/L aluminum ion, not more than about 0.2 percent chloride ion, and a fungistat consisting of benzoic acid, a water-soluble salt of benzoic acid selected from the group consisting of sodium benzoate, potassium benzoate, or lithium benzoate, or mixtures thereof, the fungistat having a concentration in the range of about one part per million (1 ppm) to about ten thousand parts per million (10,000 ppm) by weight; (b) maintaining the bath at a temperature from about 70 to about 90 degrees F.; (c) immersing the workpiece in the bath; (d) ramping the voltage applied across the workpiece in the bath from about 5 to about 20 volts such that the current density is substantially uniform across the workpiece and the average current density does not exceed about 10 amperes per square foot; and (e) maintaining the workpiece in the bath for a time such that an adherent coating of aluminum oxide is applied thereto having a coating weight between about 200 and 600 milligrams per square foot. An improved bath for anodizing aluminum or aluminum alloy workpieces comprising an aqueous anodizing solution consisting essentially by weight of: (a) from about 3 to 5 percent sulfuric acid; (b) from about 0.5 to 1 percent boric acid; (c) not more than about 5.0 g/L aluminum ion; (d) not more than about 0.2 percent chloride ion, and (e) a fungistat consisting of benzoic acid, a water-soluble salt of benzoic acid selected from the group consisting of sodium benzoate, potassium benzoate, or lithium benzoate, or mixtures thereof, the fungistat having a concentration in the range of about one part per million (1 ppm) to about ten thousand parts per million (10,000 ppm) by weight.

Growing community of inventors

Seattle, WA, United States of America

David L Crump