Vincent W Martin

6514414, Feb 4, 2003

Sep 8, 2000

09/658832

Vincent Wise Martin - Gastonia NC

Clariant Finance (BVI) Limited - Tortola

B01D 1504

210670, 210688, 210912

The present invention provides a process for the separation and removal of iron ions from a basic zinc solution. The process involves: treating an aqueous basic zinc solution with a solid ion exchange resin containing an insoluble cross-linked polymer which contains at least one pendant phosphonate group, at a pH of from about 8 to about 12, and a temperature of from about 10Â C. to about 90Â C. , for a time period sufficient to form solid phase-bound iron ions and a liquid phase containing the aqueous basic zinc solution having an iron ion concentration that is substantially reduced; separating the solid phase-bound iron ions and the liquid phase; and treating the solid phase-bound iron ions with an aqueous acidic solution under conditions sufficient to regenerate the solid ion exchange resin.

6569310, May 27, 2003

Feb 2, 2001

09/776518

Baldev K. Bandlish - Charlotte NC
Vincent Wise Martin - Gastonia NC

Clariant Finance (BVI) Limited - Tortola

C25C 116

205604, 205603

Disclosed is an electrochemical process for preparing zinc powder which involves: a) providing to an electrochemical cell a basic solution of zinc oxide or any other zinc compound that reacts with an aqueous base to produce zinc oxide, the basic solution prepared by dissolving the zinc oxide or the other zinc compound in an aqueous 2. 5 to 10. 0 M base solution; and b) passing current to the cell at a current density of about 10,000 to about 40,000 A/m for a time period sufficient to electrochemically reduce the zinc oxide to zinc powder, wherein the electrochemical process has a current efficiency of at least 70% and is substantially free from electrode corrosion.

6569311, May 27, 2003

Feb 2, 2001

09/776644

Baldev K. Bandlish - Charlotte NC
Vincent Wise Martin - Gastonia NC

Clariant Finance (BVI) Limited - Tortola

C25C 116

205604, 205603

The present invention relates to a continuous electrochemical process for preparing zinc powder. The process involves providing to an electrochemical cell a suspension in a 1. 25 Molar to 10. 0 Molar aqueous alkaline solution of zinc oxide or any other zinc compound that reacts with an aqueous alkaline solution to produce zinc oxide, such that the solution or suspension comprises at least 2 millimoles of solubilized zinc based species per 100 grams of electrolyte. Current is passed to the cell at a current density of about 500 to 40,000 A/m , for a time period sufficient to electrochemically reduce the solubilized zinc based species to zinc powder, while continuously or intermittently adding a sufficient amount of the zinc oxide or the other zinc compound to the cell to maintain the concentration of the solubilized zinc based species at a level of at least 2 millimoles per 100 grams of electrolyte.

20030057105, Mar 27, 2003

Sep 27, 2001

09/965157

Baldev Bandlish - Charlotte NC, US
Vincent Martin - Gastonia NC, US

Clariant International Ltd.

C25C001/16
C01G009/02

205/602000, 423/622000

The present invention provides a composition comprising a saturated solution of zinc oxide in an aqueous sodium or potassium hydroxide solution wherein the concentrations of the zinc oxide and the sodium hydroxide in said solution are as set forth in FIG. and the concentrations of the zinc oxide and potassium hydroxide are as set forth in FIG. The present invention also provides a process for preparing a solution of zinc oxide in an aqueous base, said process comprising diluting a more concentrated solution of zinc oxide in aqueous sodium or potassium hydroxide to produce a resulting dilute solution of zinc oxide having a concentration of zinc oxide that is higher than that obtained by dissolving solid zinc oxide in aqueous sodium or potassium hydroxide, wherein the concentration of the aqueous sodium or potassium hydroxide used for dissolving the solid zinc oxide is substantially the same as the concentration of the aqueous sodium or potassium hydroxide in the resulting dilute solution of zinc oxide, and wherein the concentration of the aqueous sodium hydroxide in the resulting dilute solution ranges from 5 wt % NaOH to about 35 wt % NaOH, and the concentration of the aqueous potassium hydroxide in the resulting dilute solution ranges from 10 wt % KOH to about 55 wt % KOH. The present invention also provides a process for producing zinc metal comprising electrolyzing a basic solution of zinc oxide prepared by the aforementioned process.

20030106806, Jun 12, 2003

Dec 7, 2001

10/015185

Baldev Bandlish - Charlotte NC, US
Vincent Martin - Gastonia NC, US

Clariant International Ltd.

C25B001/00

205/602000, 205/603000

Disclosed is a low corrosion electrochemical process for preparing zinc metal which comprises electrochemically reducing an aqueous basic solution or slurry of zinc oxide or any other zinc compound that reacts with an aqueous base to produce zinc oxide, wherein the electrochemical process is carried out in an undivided electrochemical cell, and wherein air or nitrogen is bubbled in through the solution or slurry of zinc oxide or said other zinc compound during said electrochemical process.

20030150815, Aug 14, 2003

Dec 18, 2002

10/323418

Vincent Martin - Gastonia NC, US

Clariant Finance (BVI) Limited

C02F001/42

210/670000

The present invention provides a process for the separation and removal of iron ions from a basic zinc solution. The process involves: treating an aqueous basic zinc solution with a solid ion exchange resin containing an insoluble cross-linked polymer which contains at least one pendant phosphonate group, at a pH of from about 8 to about 12, and a temperature of from about 10 C. to about 90 C., for a time period sufficient to form solid phase-bound iron ions and a liquid phase containing the aqueous basic zinc solution having an iron ion concentration that is substantially reduced; separating the solid phase-bound iron ions and the liquid phase; and treating the solid phase-bound iron ions with an aqueous acidic solution under conditions sufficient to regenerate the solid ion exchange resin. The present invention also provides a process for preparing zinc oxide that is substantially free of iron ions. This process involves: (a) treating ammonium carbonate and zinc oxide to form a mixture containing a zinc ammonia carbonate complex and metal impurities such as iron, lead, and cadmium, and optionally sulfur; (b) optionally filtering the mixture from (a) to produce a residue containing mostly sulfur and a filtrate containing mostly the zinc ammonium carbonate complex and metal impurities containing iron, lead and cadmium; (c) treating the filtrate from (b), or the mixture from (a) with zinc(0) to remove the lead and cadmium and to form a cementation product, and filtering the cementation product to form a cementation residue containing mostly lead and cadmium and a cementation filtrate containing mostly zinc and iron ions; (d) treating the cementation filtrate from (c) with the above mentioned ion exchange resin, for a time period sufficient to form solid phase-bound iron ions and a liquid phase containing the cementation filtrate having an iron ion concentration that is substantially reduced; (e) heating the liquid phase from (d) to remove ammonia and to precipitate zinc ions in solution as mostly zinc carbonate; and (f) calcining the zinc carbonate precipitate of step (e) at a temperature of from about 200 C. to about 1100 C. to convert the zinc carbonate to zinc oxide.

20030183535, Oct 2, 2003

Mar 28, 2002

10/109443

Baldev Bandlish - Charlotte NC, US
Vincent Wise Martin - Gastonia NC, US

Clariant International Ltd.

C25B001/00

205/495000

Disclosed is a process for preparing zinc dithionite comprising reacting zinc metal with sulfur dioxide, wherein the zinc metal used in the reaction is produced by electrochemical reduction in an undivided electrochemical cell of an aqueous alkaline slurry or solution of zinc oxide or any other zinc compound that reacts with aqueous base to form zinc oxide.

20030221972, Dec 4, 2003

May 30, 2002

10/158822

Baldev Bandlish - Charlotte NC, US
Vincent Martin - Gastonia NC, US

Clariant International Ltd.

C25C001/16

205/607000

The present invention provides a low corrosion electrochemical process for preparing zinc metal which comprises electrochemically reducing an aqueous alkaline slurry or solution of zinc oxide or any other compound that reacts with an aqueous base to produce zinc oxide, wherein the electrochemical process is carried out in an undivided electrochemical cell and wherein sodium bisulfide (NaSH) is added to the aqueous alkaline slurry or solution. The present invention also provides a process for preparing zinc dithionite, which comprises reacting zinc metal with sulfur dioxide, wherein the zinc metal is produced by the aforementioned electrochemical process.