RICHARD HENRY HORN
Medical Practice in Pittsburgh, PA

4549946, Oct 29, 1985

May 9, 1984

6/608512

Richard E. Horn - Pittsburgh PA

Electrochem International, Inc. - Pittsburgh PA

B01D 1302

2041824

A process and electrodialytic cell for electrodialytically regenerating an aqueous, spent electroless copper plating bath which contains alkali metal salts as reaction products of the electroless plating process. In the process, the spent copper plating bath is introduced into a regeneration compartment of an electrodialytic cell. Anions of the alkali metal salts in the spent copper plating bath are electrodialytically transferred through an anionic membrane into an acid formation compartment. Hydroxyl ions are electrodialytically transferred through the anionic portion of a bipolar membrane to a regeneration compartment to regenerate the bath. The electrodialytic cell of the invention has means for establishing and maintaining in a plurality of regeneration compartments the spent electroless copper plating bath. The apparatus also includes means for electrodialytically transferring anions of the alkali metal salts in the spent copper plating bath from a plurality of regeneration compartments into a plurality of acid formation compartments through a plurality of anionic membranes, with at least one anionic membrane being associated with each acid formation compartment. The electrodialytic cell additionally includes means for electrodialytically transferring hydroxyl ions into the regeneration compartments through the anionic portion of a plurality of bipolar membranes, with at least one bipolar membrane being associated with each acid formation compartment.

4111772, Sep 5, 1978

Aug 20, 1976

5/716225

Richard E. Horn - Pittsburgh PA

Pitt Metals and Chemicals, Inc. - Pittsburgh PA

B01D 1302, C25D 330

204180P

In one specie a tin-plating bath contains an alkali metal stannate and generates an alkali metal hydroxide during the electrodeposition of tin. The tin-plating bath is circulated through the anode compartment of an electrodialytic cell that has a cation permselective membrane separating the anode compartment from the cathode compartment. The cathode compartment contains a suitable electrolyte and when a current is impressed across the electrodialytic cell, the alkali metal ions in the plating bath migrate through the permselective membrane into the cathode compartment and the stannate ions remain in the tin-plating bath in the anode compartment. The removal of the alkali metal ions from the tin-plating bath controls the alkali metal hydroxide content of the plating bath. The electrodialytic cell may be positioned in the tin plating bath and where feasible utilize the same power source as the plating bath. Where bath drag out is excessive and the amount of alkali metal hydroxide removed from the plating bath reduces the amount of treatment of the plating bath, the alkali metal stannate is recovered from the rinse water by passing the rinse water through a center compartment of a three compartment electrodialytic cell bounded by a cation and an anion or neutral permselective membrane.

4229280, Oct 21, 1980

Apr 13, 1978

5/896058

Richard E. Horn - Pittsburgh PA

Pitt Metals & Chemicals, Inc. - Pittsburgh PA

B01D 1302, C25C 114

204301

In one specie a tin-plating bath contains an alkali metal stannate and generates an alkali metal hydroxide during the electrodeposition of tin. The tin-plating bath is circulated through the anode compartment of an electrodialytic cell that has a cation permselective membrane separating the anode compartment from the cathode compartment. The cathode compartment contains a suitable electrolyte and when a current is impressed across the electrodialytic cell, the alkali metal ions in the plating bath migrate through the permselective membrane into the cathode compartment and the stannate ions remain in the tin-plating bath in the anode compartment. The removal of the alkali metal ions from the tin-plating bath controls the alkali metal hydroxide content of the plating bath. The electrodialytic cell may be positioned in the tin plating bath and where feasible utilize the same power source as the plating bath. Where bath drag out is excessive and the amount of alkali metal hydroxide removed from the plating bath reduces the amount of treatment of the plating bath, the alkali metal stannate is recovered from the rinse water by passing the rinse water through a center compartment of a three compartment electrodialytic cell bounded by a cation and an anion or neutral permselective membrane.

4525259, Jun 25, 1985

Nov 10, 1983

6/550600

Richard E. Horn - Pittsburgh PA
Bradley D. Rodeheaver - Pittsburgh PA

Electrochem International, Inc. - McDonald PA

B01D 1302, G01N 2728

2041824

The method and apparatus for rinsing an electrodialysis electrode provides isolation from the fluid being electrodialyzed. The method utilizes the natural circulation of the liquid and provides an exchange between the anode and cathode liquids while maintaining electrical isolation to thereby improve the efficiency of the electrodialysis cell and reducing the power requirements. The method of rinsing makes use of the gas generated at the electrodes to provide a motivating fluid for circulating the electrode rinse liquid. Circulation of the fluid is carried out in the slug flow region to provide electrical isolation. In the multi chamber apparatus the chamber adjacent to both of the electrode chambers contains the dilute liquid and is positioned between the electrode chamber and the chamber containing the concentrated solution to prevent migration of ions from the concentrated solution into the electrode chamber to contaminate the electrode.

4066518, Jan 3, 1978

Aug 20, 1976

5/716234

Richard E. Horn - Pittsburgh PA

Pitt Metals and Chemicals, Inc. - Pittsburgh PA

C25B 100

204 86

Alkali metal stannates are produced in an electrochemical process by dissolving a tin anode in an appropriate alkali metal hydroxide in the anode compartment of an electrodialytic cell. The anode compartment of the electrodialytic cell is separated from a cathode compartment by an anionic or a cationic permselective ion exchange membrane. The tin is dissolved in the anode compartment in the stannous form and after reacting with the alkali metal hydroxide is oxidized to the stannic form to produce the desired alkali metal stannate.