Iron Carbide Holdings, Ltd.

E.i. Dupont De Nemours and Company

Asarco LLC

Hazen Research, Inc.

Indium Corporation of America

Resource Technology Associates

John P Hager

Frank M Stephens, Jr

Frank A Stephens

Russell Bertrum Diemer, Jr

Michael H Blenk

Taie Li

Thomas P Clement, Ii

Paul B Queneau

James E Reynolds

Robert F Hogsett

Jerome P Downey

Charles E White

Wayne W Hazen

Nicholas J Lombardo

David L Thompson

Laurence G Stevens

Nicholas B Gomez

The present invention is a process for the rapid conversion of iron oxide-containing material into iron carbide. The process includes a first step in which the iron oxide-containing material is contacted with a reducing gas that contains a high concentration of hydrogen gas to form a metallic iron-containing intermediate product and a second step in which the metallic iron-containing product is contacted with a carburizing gas having high concentrations of hydrogen and carbon monoxide gas to produce iron carbide. The unused carbon monoxide in the off-gas from the second step is not recycled to the second step but is used as a fuel source.

Process for the production of iron carbide from iron oxide using external sources of carbon monoxide

A method for treating a brass fixture having a fluid-contacting surface with lead dispersoids exposed thereon to reduce lead leaching into a fluid supply by contacting the brass fixture with a liquid metal solution selected from the group consisting of a liquid sodium solution, a liquid potassium solution and a liquid metal alloy solution to dissolve lead dispersoids from the fixture, wherein the metal alloy comprises a metal selected from the group consisting of sodium and potassium.

Method for reducing lead leaching in fixtures

A process for controlling the conversion of reactor feed to iron carbide is disclosed. The reactor feed is subjected to a process gas in a fluidized bed reactor (10), and the off-gas from this reaction is analyzed (56) to determine its composition and the temperature (64) and pressure (66). A stability phase diagram is generated based on the temperature. Different regions of the stability phase diagram are representative of different products being formed by the conversion of the reactor feed. Based on relative concentrations of the individual gases in the off-gas and the total pressure, a point is plotted on the stability phase diagram indicative of the favored reaction product. The process parameters can then be adjusted to insure that iron carbide can be produced from the reactor feed based on the stability phase diagram. In one embodiment, the rate of conversion of the reactor feed into iron carbide is controlled.

Method for controlling the conversion of iron-containing reactor feed

A process for using iron metal or an iron-containing sulfide reagent as a co-additive to extend the usefulness of sodium in refining crude lead bullion.

Iron as a co-additive in refining crude lead bullion

Previously formed copper speiss in an amount of about 6.5% by weight is a co-additive which extends the usefulness of sodium in refining crude lead bullion, which has a sulfur content generally less than about 1.3% by weight.

Copper speiss as a co-additive in refining crude lead bullion

A process for using an iron-containing sulfide reagent and a previously formed copper speiss as joint co-additives to extend the usefulness of the sodium in refining crude bullion which has less than about 1.3 wt. % sulfur.

Iron and a copper speiss as co-additives in refining crude lead bullion

A novel process for the conversion of reactor feed to iron carbide is provided. The process includes the step of preheating the reactor feed in an oxidizing atmosphere. The iron carbide produced by the process is particularly useful in the production of steel.

Process for preheating iron-containing reactor feed prior to being

A novel design for a fluidized bed reactor is provided. The fluidized bed reactor includes a baffle system to ensure the proper residence time of the feed materials. The fluidized bed reactor also provides a novel method for reducing the negative effects of thermal expansion in the reactor.

Process for using fluidized bed reactor

Fume generated by roasting speiss is contacted with an oxygen-containing gas at an elevated temperature for a sufficient time to product arsenic and antimony products which may be separated from each other by means such as condensation. Further, in the roasting of antimony-containing phases (such as speiss) the presence of arsenic can enhance the volatility of the antimony.

Process for the recovery and separation of arsenic from antimony

Indium-containing feedstocks, such as flue dusts from a refining or smelting process, are treated to increase the concentration of indium and at the same time to reduce the concentrations of lead, copper, and arsenic. The flue dusts are treated in a sodium-doped lead bath at temperatures of 675.degree. to 800.degree. C. Soda ash in the amount of 15 to 35 weight percent is blended with the feed stock and added to the sodium-doped lead bullion. The sodium reacts with the dusts to form a liquid dross, which is removed, cooled, and crushed. The powdered dross is water leached to remove the sodium salts. The indium remains in the filler cake and can be processed by conventional methods for the recovery of indium. About 95% of the indium reports to the filter cake, while lead retention in the filter cake is only about 5-15% of the initial lead content in the dust. A majority of the zinc also reports to the filter cake. A majority of the lead, copper, and silver report to the bullion, and a majority of the arsenic reports to the filtrate. Sodium consumption is about one pound of sodium for each five to ten pounds of feedstock.

Treatment of indium dusts

A method of controlling product quality in a conversion of reactor feed to an iron carbide-containing product in a fluidized bed reactor. A Mossbauer analysis is performed on product samples leaving the fluidized bed reactor, and a regression analysis is performed on the Mossbauer data. Depending upon the results of the regression analysis, process parameters are adjusted in order to obtain a product having a desired composition. Adjustments are made to the temperature and pressure in the fluidized bed reactor, rate of feed to the fluidized bed reactor, and the composition of the process gas which reacts with the reactor feed in the fluidized bed reactor, dependent upon the analysis results.

Process for controlling the product quality in the conversion of reactor

Fume generated by roasting speiss is contacted with an oxygen-containing gas at an elevated temperature for a sufficient time to produce arsenic and antimony products which may be separated from each other by means such as condensation. Further, in the roasting of antimony-containing phases (such as speiss) the presence of arsenic can enhance the volatility of the antimony.

A novel process for the recovery of alumina and potassium sulfate from alunite is provided comprising leaching the alunite with potassium hydroxide to which no sodium materials have been added, said leach solution being saturated with potassium sulfate. Aluminum values are solubilized into the leachate, and potassium and sulfur values are rendered soluble, but remain in the residue. The leachate is desilicated if necessary, preferably with lime, and aluminum trihydroxide is precipitated therefrom, followed by calcining to alumina product. The residue is leached to solubilize potassium sulfate in a secondary leach and the potassium sulfate product crystallized therefrom. Potassium hydroxide is regenerated from a portion of the potassium sulfate secondary leachate by several methods. Novel procedures for regenerating alkali metal hydroxides from the corresponding sulfates are also provided including routes involving formates and carbonates as intermediates and pyrohydrolysis.

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Golden, CO, United States of America

John P Hager