Robert Kimball Dawless

US Patent:

44117477, Oct 25, 1983

Filed:

Aug 30, 1982

Appl. No.:

6/412833

Inventors:

Robert K. Dawless - Monroeville PA
Kenneth A. Bowman - Leechburg PA
Robert M. Mazgaj - Lower Burrell PA
C. Norman Cochran - Oakmont PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C25C 306
C22B 2102

US Classification:

204 67

Abstract:

A method for purifying aluminum that contains impurities, the method including the step of introducing such aluminum containing impurities to a charging and melting chamber located in an electrolytic cell of the type having a porous diaphragm permeable by the electrolyte of the cell and impermeable to molten aluminum. The method includes further the steps of supplying impure aluminum from the chamber to the anode area of the cell and electrolytically transferring aluminum from the anode area to the cathode through the diaphragm while leaving impurities in the anode area, thereby purifying the aluminum introduced into the chamber. The method includes the further steps of collecting the purified aluminum at the cathode, and lowering the level of impurities concentrated in the anode area by subjecting molten aluminum and impurities in said chamber to a fractional crystallization treatment wherein eutectic-type impurities crystallize and precipitate out of the aluminum. The eutectic impurities that have crystallized are physically removed from the chamber. The aluminum in the chamber is now suited for further purification as provided in the above step of electrolytically transferring aluminum through the diaphragm.

US Patent:

42396069, Dec 16, 1980

Filed:

Dec 26, 1979

Appl. No.:

6/107149

Inventors:

Robert K. Dawless - Monroeville PA
Stanley C. Jacobs - Lower Burrell PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C25C 306

US Classification:

204 67

Abstract:

A process for purifying impure aluminum comprises introducing the impure aluminum to the anode layer of an electrolytic cell of the type having a bottom layer of molten aluminum-copper alloy constituting the anode layer and having a top layer of molten aluminum constituting a cathode layer, the cathode and anode layers separated by an electrolyte layer. Aluminum is electrolytically transported from the anode to the cathode in a first purification step and then fractionally crystallized to remove further impurities therefrom by crystallizing pure aluminum and thereafter separating the molten remaining part, which is high in impurities, from the purified aluminum. The impure molten aluminum portion is then recycled back to the electrolytic cell or to another fractional crystallization step.

US Patent:

60305185, Feb 29, 2000

Filed:

Sep 10, 1997

Appl. No.:

8/926530

Inventors:

Robert K. Dawless - Monroeville PA
Siba P. Ray - Murrysville PA
Robert B. Hosler - Sarver PA
Robert L. Kozarek - Apollo PA
Alfred F. LaCamera - Trafford PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C25C 306
C25C 308
C25C 318

US Classification:

205387

Abstract:

Aluminum is produced by electrolytic reduction of alumina in a cell having a cathode, an inert anode and a molten salt bath containing metal fluorides and alumina. The inert anode preferably contains copper, silver and oxides of iron and nickel. Reducing the molten salt bath temperature to about 900-950. degree. C. lowers corrosion on the inert anode constituents.

US Patent:

43128483, Jan 26, 1982

Filed:

Sep 9, 1980

Appl. No.:

6/185597

Inventors:

Robert K. Dawless - Monroeville PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

B01D 900
C01B 3302

US Classification:

423348

Abstract:

A method of removing boron impurity in a process for purifying silicon is disclosed wherein silicon is crystallized from a solvent metal. The method comprises the steps of providing a molten body containing silicon, the remainder aluminum and impurities and providing a metal selected from the group consisting of titanium, vanadium and zirconium therein, the metal from the group forming a reaction product with boron and permitting the reaction product to settle in the body for removal purposes.

US Patent:

42736277, Jun 16, 1981

Filed:

Dec 26, 1979

Appl. No.:

6/107138

Inventors:

Robert K. Dawless - Monroeville PA
Stanley C. Jacobs - Lower Burrell PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

C25C 306

US Classification:

204 67

Abstract:

A process for purifying impure aluminum comprises introducing the impure aluminum to the anode layer of an electrolytic cell of the type having a bottom layer of molten aluminum-copper alloy constituting the anode layer and having a top layer of molten aluminum constituting a cathode layer, the cathode and anode layers separated by an electrolyte layer. Aluminum is electrolytically transported from the anode to the cathode in a first purification step and then treated with a carbonaceous material to remove magnesium therefrom. Thereafter, the treated portion is fractionally crystallized to remove further impurities therefrom by crystallizing pure aluminum and separating the molten remaining part, which is high in impurities, from the purified aluminum. The impure molten aluminum portion is then recycled back to the electrolytic cell or to another fractional crystallization step.

US Patent:

61267996, Oct 3, 2000

Filed:

Feb 1, 1999

Appl. No.:

9/241518

Inventors:

Siba P. Ray - Murrysville PA
Robert W. Woods - New Kensington PA
Robert K. Dawless - Monroeville PA
Robert B. Hosler - Sarver PA

Assignee:

Alcoa Inc. - Pittsburgh PA

International Classification:

C25B 1100

US Classification:

204291

Abstract:

A cermet composite material is made by treating at an elevated temperature a mixture comprising a compound of iron and a compound of at least one other metal, together with an alloy or mixture of copper and a noble metal. The alloy or mixture preferably comprises particles having an interior portion containing more copper than noble metal and an exterior portion containing more noble metal than copper. The noble metal is preferably silver. The cermet composite material preferably includes alloy phase portions and a ceramic phase portion. At least part of the ceramic phase portion preferably has a spinel structure.

US Patent:

42567173, Mar 17, 1981

Filed:

May 24, 1979

Appl. No.:

6/041892

Inventors:

Robert K. Dawless - Monroeville PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

B01D 900
C01B 3302

US Classification:

423348

Abstract:

A method for purifying silicon comprises the steps of providing a body of molten silicon-rich material and extracting heat therefrom to provide a solid phase containing silicon in crystal form and to concentrate impurities in a molten phase. After a desired amount of heat has been extracted, a substantial part of the molten phase is separated from the solid phase. A fraction or portion of the solid phase is remelted for purposes of removing solvent metal, including impurities, from the crystals, and at least one fraction of the remelted material is separated from the crystals.

US Patent:

48225851, Apr 18, 1989

Filed:

May 5, 1982

Appl. No.:

6/374931

Inventors:

Robert K. Dawless - Monroeville PA

Assignee:

Aluminum Company of America - Pittsburgh PA

International Classification:

B01D 900

US Classification:

423348

Abstract:

A method for purifying silicon comprises the steps of providing a body of molten silicon-rich material in a solvent metal comprising copper or copper-aluminum combination and extracting heat therefrom to provide a solid phase containing silicon in crystal form and to concentrate impurities in a molten phase. After a desired amount of heat has been extracted, a substantial part of the molten phase is separated from the solid phase. A fraction or portion of the solid phase is remelted for purposes of removing solvent metal comprising copper or copper-aluminum solvent metal, including impurities, from the crystals, and at least one fraction of the remelted material is separated from the crystals.