Patents by Inventor Robert D. Hansen

Robert D. Hansen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5057209
    Abstract: A flotation process is disclosed wherein the selectivity to the valuable mineral is improved by the depression of silica or siliceous gangue by the use of a hydroxy-containing compound such as an alkanol amine. The process is useful in the flotation of oxide minerals as well as in sulfide flotation.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: October 15, 1991
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Donald E. Leonard, Robert D. Hansen, Basil S. Fee
  • Patent number: 4830740
    Abstract: The separation of coal from pyrite is enhanced by the use of an effective amount of a polymeric acid or salt thereof as a pyrite depressant in conventional flotation processes. The polymeric acid may be a carboxylic or sulfonic acid. An example of a salt of a polymeric acid useful in the process is sodium polyacrylate.
    Type: Grant
    Filed: April 19, 1988
    Date of Patent: May 16, 1989
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4826588
    Abstract: The separation of coal from pyrite during a froth flotation process is enhanced by the use of an effective amount of a pyrite depressant. The depressant is a hydrophilic nitrogen-sulfur-containing compound.
    Type: Grant
    Filed: April 28, 1988
    Date of Patent: May 2, 1989
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen, Michael J. Fazio
  • Patent number: 4822483
    Abstract: A collector composition for use in froth flotation processes comprises two collectors. One of the collectors is preferably an N-(hydrocarbyl)-alpha, omega-alkanediamine, an (omega-aminoalkyl) hydrocarbon amide or mixture thereof. The second collector is a thiocarbonate, a thionocarbamate, a thiophosphate, thiocarbinilide, thiophosphinate, mercaptan, xanthogen formate, xanthic ester or mixture thereof. The collector composition floats a broad range of metal-containing minerals.
    Type: Grant
    Filed: March 23, 1987
    Date of Patent: April 18, 1989
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4820406
    Abstract: The froth flotation of coal is conducted in the presence of an epoxide conditioner.
    Type: Grant
    Filed: May 6, 1987
    Date of Patent: April 11, 1989
    Assignee: The Dow Chemical Company
    Inventors: Robert D. Hansen, Richard R. Klimpel
  • Patent number: 4808301
    Abstract: The flotation of desired mineral ores is selectively depressed by the use of an effective amount of a polycarboxylic acid or salt thereof in a reverse flotation process. As an example, the flotation of iron-containing minerals, such as iron oxides or iron powder, is selectively depressed when compared to the flotation of silicate gangue thus facilitating the recovery of the desired mineral by the use of an effective amount of a polycarboxylic acid or salt thereof such as sodium polyacrylate.
    Type: Grant
    Filed: November 4, 1987
    Date of Patent: February 28, 1989
    Assignee: The Dow Chemical Company
    Inventors: Robert D. Hansen, Richard R. Klimpel
  • Patent number: 4797202
    Abstract: Minerals are recovered from ore by subjecting the ore, in the form of an aqueous pulp, to a froth flotation process in the presence of a collector of the formula:R.sup.1 --X--(R).sub.n --N--(R.sup.2).sub.2 (Ia)orR.sup.1 --X--(R).sub.n --N=Y (Ib)wherein --(R).sub.n -- is ##STR1## each R' is independently hydrogen, methyl or ethyl; y+p+m=n; n is an integer from 1 to 6; y and m are independently 0 or 1 and y+m=0 or 1 and p is an integer from 1 to 6 and each moiety can occur in random sequence; R.sup.1 is a C.sub.1-22 hydrocarbyl or a C.sub.1-22 substituted hydrocarbyl and each R.sup.2 is independently hydrogen, a C.sub.1-22 hydrocarbyl or a C.sub.1-22 substituted hydrocarbyl; --X-- is --N(R.sup.3)-- or ##STR2## R.sup.3 is H or a C.sub.1-22 hydrocarbyl or a C.sub.1-22 substituted hydrocarbyl; =Y is =S, =O, a hydrocarbylene or a substituted hydrocarbylene radical.
    Type: Grant
    Filed: February 26, 1987
    Date of Patent: January 10, 1989
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4789392
    Abstract: Minerals are recovered from ore by subjecting the ore, in the form of an aqueous pulp, to a froth flotation process in the presence of a collector of the formula:R.sup.1 --X--(R).sub.n --N--(R.sup.2).sub.2 or (Ia)R.sup.1 --X--(R).sub.n --N.dbd.Y (Ib)wherein (--R--).sub.n is ##STR1## each R' and R" is independently hydrogen, methyl or ethyl; y+p+m=n; n is an integer from 1 to 6; y and m are independently 0 or 1 and y+m=0 or 1 and p is an integer from 1 to 6 and each moiety can occur in random sequence; R.sup.1 is a C.sub.1-22 hydrocarbyl or a C.sub.1-22 substituted hydrocarbyl; each R.sup.2 is independently hydrogen, a C.sub.1-22 hydrocarbyl or a C.sub.1-22 substituted hydrocarbyl; --X-- is --S-- or ##STR2## and .dbd.Y is .dbd.S, .dbd.O, a hydrocarbylene or a substituted hydrocarbylene radical.
    Type: Grant
    Filed: February 26, 1987
    Date of Patent: December 6, 1988
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4770767
    Abstract: The froth flotation of coal is conducted in the presence of a conditioner of an oxygen containing compound of the formula:R.sub.1 --O--R.sub.2).sub.n (I)wherein R.sub.1 and each R.sub.2 are independently saturated hydrocarbyls and n is from 1 to about 3.
    Type: Grant
    Filed: May 6, 1987
    Date of Patent: September 13, 1988
    Assignee: The Dow Chemical Company
    Inventors: Robert D. Hansen, Richard R. Klimpel
  • Patent number: 4761223
    Abstract: The invention is a process for recovering coal from raw coal which comprises subjecting the raw coal in the form of an aqueous pulp, to a flotation process in the presence of a flotation collector, and a flotating amount of a flotation frother which comprises the reaction product of a polyhydroxy C.sub.1-20 alkane or polyhydroxy C.sub.3-20 cycloalkane and propylene oxide, or a mixture of propylene oxide and ethylene oxide, with the proviso that at least 50 mole percent of the mixture is propylene oxide, and the reaction product has a molecular weight of between about 150 and 1400, under conditions such that the coal is recovered.
    Type: Grant
    Filed: August 29, 1984
    Date of Patent: August 2, 1988
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4735711
    Abstract: This invention relates to a froth flotation process for selectively recovering metal-containing sulfide or sulfidized metal-containing oxide minerals from ores using a froth flotation process. The collector employed in the process is an organic monosulfide of the formula:R.sub.1 --S--R.sub.2wherein R.sub.1 is a methyl, ethyl, epoxy (i.e., ##STR1## group or R.sub.3 --S--R.sub.4 wherein R.sub.3 is a hydrocarbyl or substituted hydrocarbyl group and R.sub.4 is a hydrocarbylene or substituted hydrocarbylene; and R.sub.2 is an alkyl or cycloalkyl group having from 5 to 11 carbon atoms.
    Type: Grant
    Filed: May 6, 1986
    Date of Patent: April 5, 1988
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen, Edwin J. Strojny
  • Patent number: 4732668
    Abstract: This invention relates to a froth flotation process for selectively recovering nonferrous metal-containing sulfide minerals or sulfidized metal-containing oxide minerals from ores using froth flotation. The collector employed in the process is an epithio compound of the formula: ##STR1## wherein m=1, 2 or 3; each R is independently hydrogen, a hydrocarbyl group or substituted hydrocarbyl group; each R.sup.1 is independently hydrogen, a hydrocarbyl group or substituted hydrocarbyl group, provided one R or R.sup.1 is not hydrogen; and each R.sup.2 is independently hydrogen, hydrocarbyl, hydrocarbyloxy or hydrocarbyl thioether.
    Type: Grant
    Filed: May 6, 1986
    Date of Patent: March 22, 1988
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen, Edwin J. Strojny
  • Patent number: 4702822
    Abstract: This invention relates to a novel composition which is useful as a collector for the recovery of nonferrous metal-containing sulfide minerals and sulfidized metal-containing oxide minerals from ores in a froth flotation process. The novel composition comprises (a) an organic compound containing one or more monosulfide units wherein the sulfur atom(s) are bound to aliphatic or cycloaliphatic carbon atoms, and the total carbon content of the compound is such that the compound has sufficient hydrophobic character to cause metal-containing sulfide mineral or sulfidized metal-containing oxide mineral particles to be driven to an air/bubble interface; and (b) an alkyl thiocarbonate, a thionacarbamate, a thiophosphate, or mixtures thereof.
    Type: Grant
    Filed: June 18, 1986
    Date of Patent: October 27, 1987
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4684459
    Abstract: A collector composition for use in froth flotation processes comprises two collectors. One of the collectors is preferably an omega-(hydrocarbylthio)alkylamine, S-(omega-aminoalkyl) hydrocarbyl thioate, N-(hydrocarbyl)-alpha, omega-alkanediamine, (omega-aminoalkyl) hydrocarbon amide, omega-(hydrocarbyloxy)alkylamine, omega-aminoalkyl hydrocarbonoate or mixture thereof. The second collector is a thiocarbonate, a thionocarbamate, a thiophosphate, thiocarbinilide, thiophosphinate, mercaptan, xanthogen formate, xanthic ester or mixture thereof. The collector composition floats a broad range of metal-containing minerals.
    Type: Grant
    Filed: April 28, 1986
    Date of Patent: August 4, 1987
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4676890
    Abstract: A collector composition useful for the recovery of metal values from metal ores in a froth flotation process comprises two collectors. One collector is an organic compound containing at least 4 carbon atoms and one or more monosulfide units, wherein the carbon atoms to which the sulfur atoms are bound are aliphatic or cycloaliphatic carbons. The other collector is preferably an omega-(hydrocarbylthio)alkylamine, S-(omega-aminoalkyl)hydrocarbyl thioate, N-(hydrocarbyl)-alpha, omega-alkanediamine, N-(omega-aminoalkyl)hydrocarbon amide, omega-(hydrocarbyloxy)alkalamine, omega-aminoalkyl hydrocarbonate or mixture thereof. The collector composition floats a broad range of metal values including sulfide ores, oxide ores and precious metals.
    Type: Grant
    Filed: April 28, 1986
    Date of Patent: June 30, 1987
    Assignee: The Dow Chemical Company
    Inventors: Richard R. Klimpel, Robert D. Hansen
  • Patent number: 4582596
    Abstract: The invention is a process for recovering coal or mineral values from raw coal or mineral ore which comprises subjecting the raw coal or mineral ore in the form of an aqueous pulp, to a floatation process in the presence of a floatation collector, and a flotating amount of a floatation frother which comprises the reaction product of an alitphatic C.sub.6 alcohol and between about 1 and 5 moles of propylene oxide, butylene oxide or mixtures thereof, under conditions such that the coal or mineral values are recovered.
    Type: Grant
    Filed: June 4, 1984
    Date of Patent: April 15, 1986
    Assignee: The Dow Chemical Company
    Inventors: Robert D. Hansen, Roger W. Bergman, Richard R. Klimpel
  • Patent number: RE32778
    Abstract: The invention is a process for recovering coal or mineral values from raw coal or mineral ore which comprises subjecting the raw coal or mineral ore in the form of an aqueous pulp, to a floatation process in the presence of a floatation collector, and a flotating amount of a floatation frother which comprises the reaction product of an alitphatic C.sub.6 alcohol and between about 1 and 5 moles of propylene oxide, butylene oxide or mixtures thereof, under conditions such that the coal or mineral values are recovered.
    Type: Grant
    Filed: October 27, 1986
    Date of Patent: November 8, 1988
    Assignee: The Dow Chemical Company
    Inventors: Robert D. Hansen, Richard R. Klimpel, Roger W. Bergman
  • Patent number: D670511
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: November 13, 2012
    Assignee: Endgrain, LLC
    Inventor: Robert D. Hansen, Jr.
  • Patent number: D682584
    Type: Grant
    Filed: September 24, 2012
    Date of Patent: May 21, 2013
    Assignee: Endgrain, LLC
    Inventor: Robert D. Hansen, Jr.
  • Patent number: D684412
    Type: Grant
    Filed: September 24, 2012
    Date of Patent: June 18, 2013
    Assignee: Endgrain, LLC
    Inventor: Robert D. Hansen, Jr.