Patents Assigned to Dow Chemical Company
  • Process for removing H.sub.2 S from sour gases with generation of a Claus feed gas
    Patent number: 4289738
    Abstract: Sour industrial gases containing carbon dioxide and hydrogen sulfide are treated with amines to remove the CO.sub.2 and H.sub.2 S. The amine absorbent containing or loaded with H.sub.2 S and CO.sub.2 is regenerated and the off-gas containing concentrated amounts of H.sub.2 S and CO.sub.2 is treated in a second amine absorber to produce an amine absorbent loaded with H.sub.2 S. This amine is then regenerated to provide an off-gas containing a high ratio of H.sub.2 S to CO.sub.2 which makes it suitable for use as the feed gas to a sulfur recovery unit such as a Claus plant. The process is automatically controlled so that the concentration of H.sub.2 S in the second amine absorber is built up to and controlled at a desired set point so that the off-gas has the required H.sub.2 S/CO.sub.2 ratio.
    Type: Grant
    Filed: July 22, 1980
    Date of Patent: September 15, 1981
    Assignee: The Dow Chemical Company
    Inventors: Roscoe L. Pearce, Charles W. Martin
  • Fusion processing of synthetic thermoplastic resinous materials
    Patent number: 4289807
    Abstract: Apparatus and method for the fusion processing of synthetic thermoplastic resinous materials, utilizing a first high-velocity stream of gas to transport the resinous material through an elongated passageway which directs the stream of gas and transported material onto a workpiece, thereby fusing the resinous material. The elongated passageway is defined by at least one wall having a plurality of foramina or pores through which a second stream of gas is directed to heat the resinous material to a fusion temperature and to provide a slip stream on the inner surface of the wall thereby preventing the resinous material from sticking to the surface. The first stream of gas may be heated to initiate or supplement the heating of the resinous material.
    Type: Grant
    Filed: March 3, 1980
    Date of Patent: September 15, 1981
    Assignee: The Dow Chemical Company
    Inventors: Marvin M. Christensen, Richard E. Zachary, Andra P. Dupont
  • Catalyst for the preparation of ethylenimine
    Patent number: 4289656
    Abstract: A dehydration catalyst and process for making an alkylenimine from an alkanolamine wherein the catalyst contains oxides of either tantalum or niobium together with the oxides of iron and chromium and in which the ratios of the metals areM.sub.10 Fe.sub.0.5-2.9 Cr.sub.0.3-1.7wherein M is tantalum or niobium.
    Type: Grant
    Filed: July 17, 1980
    Date of Patent: September 15, 1981
    Assignee: The Dow Chemical Company
    Inventors: William V. Hayes, David L. Childress
  • Method and composition for removing sulfide-containing scale from metal surfaces
    Patent number: 4289639
    Abstract: An aqueous cleaning composition is described herein which contains glyoxylic acid dissolved in an aqueous non-oxidizing acid. This cleaning solution is effective in removing acid-soluble, sulfide-containing scale from metal surfaces (e.g. refinery equipment) without the evolution of gaseous hydrogen sulfide.
    Type: Grant
    Filed: October 3, 1980
    Date of Patent: September 15, 1981
    Assignee: The Dow Chemical Company
    Inventor: Gary R. Buske
  • Method of water-solubilizing high performance polyether epoxide resins, the solubilized resins and thermoset, hydrophobic coatings derived therefrom
    Patent number: 4289812
    Abstract: Hydrophobic, thermoset resins having highly desirable properties in coatings applications can be prepared from novel, water-thinnable, base-neutralized, acidic reaction products of orthophosphoric acid with hydrophobic, nominally-difunctional polyether epoxide resins having average epoxide equivalent weights (EEW) of from about 172 to about 5500. The phosphate groups in these products, when formed with fugitive bases, are thermally decomposable to yield resins which are not rapidly self-converting as such but are rapidly heat convertible in admixture with any of several types of curing agents. The functional groups responsible for water solubilization are utilized (and reacted out) in curing of the resins. The invention provides a method of utilizing hydrophobic, high performance polyether epoxide type polymers in aqueous coating systems having the ability to wet metal surfaces.
    Type: Grant
    Filed: March 12, 1979
    Date of Patent: September 15, 1981
    Assignee: The Dow Chemical Company
    Inventor: Patrick H. Martin
  • Decomposition inhibitors for high temperature storage and distillation of chlorinated phenols
    Patent number: 4288296
    Abstract: The decomposition of chlorinated phenols, especially pentachlorophenol, during exposure to high temperatures (e.g., storage and distillation) is markedly reduced by incorporating into the molten chlorinated phenol at least about 0.25 percent by weight of said impure chlorinated phenol of at least one monohydric primary alcohol having at least 14 carbon atoms, one hydroxyl group, and devoid of any other heteroatoms or ether linkages; selected from the group consisting of straight-chain or branched monohydric primary alcohols or a mixture of said straight-chain or branched monohydric primary alcohols.
    Type: Grant
    Filed: February 1, 1980
    Date of Patent: September 8, 1981
    Assignee: The Dow Chemical Company
    Inventor: Leonard R. Thompson
  • Hydrocarbon polyl gem-bis(t-alkylperoxy)alkanoates derived from .beta.-keto-acids
    Patent number: 4288379
    Abstract: The title compounds are useful vinyl polymerization initiators of high thermal stability and correspond to the formula: ##STR1## wherein R is an x-valent hydrocarbon whose chain length can be interrupted by one or more ether linkages, R' is an aliphatic moiety of 1 to about 10 carbon atoms, R" is a tertiary hydrocarbon, and x is an integer of at least 2.
    Type: Grant
    Filed: May 31, 1977
    Date of Patent: September 8, 1981
    Assignee: The Dow Chemical Company
    Inventor: Duane B. Priddy
  • Glycol compositions containing an ether modified silicone to inhibit gelling
    Patent number: 4287077
    Abstract: Gellation resistant aqueous glycol and glycol ether compositions useful as antifreeze compositions are disclosed containing silicates together with other corrosion inhibitors. The silicates are added to the glycol compositions after the other additives have been added and after the composition has been adjusted to a pH range of 7-12. The gellation resistance is obtained or enhanced by the addition of an effective amount of a glycol soluble ether modified silicone having the repeating units ##STR1## wherein x has an average value range from 1.8 to 6.8y has an average value range from 1 to 4Z has the formula--R--C.sub.n H.sub.2n O--.sub.m R.sub.1wheren is 2 or 3m has an average value such that the average molecular weight of the polyoxyalkylene chain is in the range 100-400R is an alkylene chain of 2-4 carbons andR.sub.1 is selected from the group consisting of hydrogen and alkyl groups of 1-4 carbons.
    Type: Grant
    Filed: September 29, 1980
    Date of Patent: September 1, 1981
    Assignee: The Dow Chemical Company
    Inventor: Phillip L. Wing
  • Alkyl-substituted phenyl ether amine collectors in flotation
    Patent number: 4287052
    Abstract: In the beneficiation of phosphate ore by flotation of siliceous material, the use of an alkyl-substituted phenyl ether amine or a hydroxyalkylated derivative thereof as a collector affords improved separation of phosphate from the siliceous matter.
    Type: Grant
    Filed: April 7, 1980
    Date of Patent: September 1, 1981
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Donald A. Tomalia
  • Filler mixtures and thermoset resins containing same
    Patent number: 4287115
    Abstract: Filler mixtures containing an amorphous-pyrogenic or fumed silica and a micro or short fiber filler material such as calcium silicate are useful in preparing trowelable thermosettable resin compositions. They are particularly suitable for use in epoxy resin compositions.
    Type: Grant
    Filed: November 13, 1979
    Date of Patent: September 1, 1981
    Assignee: The Dow Chemical Company
    Inventor: Bobby Legler
  • Preparation of metal organopolyphosphate coordination of complexes
    Patent number: 4287131
    Abstract: Metal alkoxides are reacted with phosphorus pentoxide to produce metal organopolyphosphate coordination polymers.
    Type: Grant
    Filed: January 28, 1980
    Date of Patent: September 1, 1981
    Assignee: The Dow Chemical Company
    Inventors: Horst G. Langer, Thomas P. Brady
  • Isostatic molding process and seal
    Patent number: 4285896
    Abstract: In the isostatic molding of linings, an improved flange-to-flange seal is obtained when a generally rectangular ring is employed in a generally rectangular groove.
    Type: Grant
    Filed: June 6, 1977
    Date of Patent: August 25, 1981
    Assignee: The Dow Chemical Company
    Inventors: Arnold B. Miller, Herman F. Casper
  • Novel tetrazolo [4,5-C][1,2,3]benzotriazines
    Patent number: 4286090
    Abstract: Tetrazolobenzotriazine compounds such as 7-chlorotetrazolo[4,5-C][1,2,3]benzotriazine are prepared by the reaction of the corresponding substituted 5-(2-aminophenyl)tetrazole with nitrous acid. These new compounds are useful as initiating explosives, propellants, and chemical blowing agents.
    Type: Grant
    Filed: February 15, 1980
    Date of Patent: August 25, 1981
    Assignee: The Dow Chemical Company
    Inventors: Thomas C. Britton, Eugene R. Wagner
  • Dual, independently supported catalyst mixtures
    Patent number: 4285834
    Abstract: A catalyst mixture containing at least two independently supported catalysts, at least one of which is an inorganic halide supported titanium and/or vanadium Ziegler type catalyst and at least one other is an inorganic oxide supported, chromium catalyst.These catalyst mixtures are suitable for polymerizing one or more .alpha.-olefins.
    Type: Grant
    Filed: December 31, 1979
    Date of Patent: August 25, 1981
    Assignee: The Dow Chemical Company
    Inventors: Kirby Lowery, Jr., Fred L. Vance, Jr.
  • Bag transfer device
    Patent number: 4284301
    Abstract: Apparatus for clamping and transferring to another location a stack of thermoplastic bags or the like wherein the bag walls have varying thicknesses. The apparatus preferably includes sets of clamping jaws for grasping the stack of bags. Each set comprises two pairs of the jaws. One pair is designed to rigidly clamp upon the stack while the other pair is spring-loaded or otherwise adjustable so that it can close differently than the first pair to compensate for the varying bag thicknesses even when the pairs of jaws are closed by the same drive mechanism. Each set of clamping jaws is independent of the other so that they can operate independently if one set were to jam.
    Type: Grant
    Filed: April 9, 1979
    Date of Patent: August 18, 1981
    Assignee: The Dow Chemical Company
    Inventors: Herbert B. Geiger, David A. Smith
  • Efficient handling and charging system for expanded, low-density, loose-fill packaging material(s)
    Patent number: 4284372
    Abstract: A continuous handling and dispensing system for pneumatically conveyable, particulate packaging materials, such as foamed plastic dunnage, involves continuous, air-entrained circulation of the material in an essentially closed loop header installation. The header is most advantageously connected to a plurality of dispensing hoppers. Baffles are employed to deflect gas and material into the hoppers and prevent plugging of the header.
    Type: Grant
    Filed: November 19, 1979
    Date of Patent: August 18, 1981
    Assignee: The Dow Chemical Company
    Inventor: Layle V. Smith
  • Preparation of glycidyl ethers
    Patent number: 4284573
    Abstract: A process for producing glycidyl ethers of phenols is described which comprises the steps of:(1) reacting by contacting, in liquid phase, a phenol with excess epichlorohydrin in the presence of a catalytic amount of tetrahydrocarbyl phosphonium bicarbonate salt, to thereby produce a coupled reaction product comprising the corresponding propylenechlorohydrin ether of said phenol;(2) devolatilizing said coupled reaction product to remove excess epichlorohydrin and volatile by-products; and(3) contacting the devolatilized reaction product from Step (2) with aqueous base, thereby converting the propylenechlorohydrin groups of the coupled reaction product to glycidyl ether groups.This process is particularly useful in preparing low molecular weight liquid epoxy resins by the reaction of epichlorohydrin with bisphenol A.
    Type: Grant
    Filed: October 1, 1979
    Date of Patent: August 18, 1981
    Assignee: The Dow Chemical Company
    Inventors: John F. Arnett, George A. Doorakian
  • Support, catalyst and process for polymerizing olefins
    Patent number: 4283515
    Abstract: Olefins are polymerized in the presence of a catalyst which is prepared by the controlled reaction of an aliphatic alcohol such as n-propyl alcohol and a mixture of an alkyl magnesium compound such as n-butyl, sec-butyl magnesium and a silicon tetrahalide such as SiCl.sub.4. After washing the precipitate several times with a hydrocarbon such as hexane, it is suspended in a hydrocarbon such as hexane and a titanium compound such as TiCl.sub.4 is added after which a suitable reducing agent such as diethyl aluminum chloride is added. The thus formed solid catalyst is washed several times with a hydrocarbon solvent such as hexane.
    Type: Grant
    Filed: June 17, 1980
    Date of Patent: August 11, 1981
    Assignee: The Dow Chemical Company
    Inventor: Ronald L. Gibbs
  • Fire-retardant composition containing derivatives of polyphosphoric acid partial esters
    Patent number: 4283501
    Abstract: Cellulosic substrates, e.g., wood, textiles, or paper, have increased fire resistance when there are added thereto one or more compounds of the formula ##STR1## wherein M and R are specified substituents.
    Type: Grant
    Filed: January 28, 1980
    Date of Patent: August 11, 1981
    Assignee: The Dow Chemical Company
    Inventors: Thomas P. Brady, Horst G. Langer
  • Removal of copper containing incrustations from ferrous surfaces
    Patent number: RE30714
    Abstract: .Iadd.The invention concerns a method of removing copper from a ferrous metal surface without excessive corrosion of the ferrous metal surface. In the method, the copper is dissolved with an aqueous alkaline solution containing a ferric chelate of an alkylene polyamine polyacetic acid chelating agent. .Iaddend.
    Type: Grant
    Filed: September 14, 1978
    Date of Patent: August 18, 1981
    Assignee: The Dow Chemical Company
    Inventors: Lester W. Harriman, Paul E. Muehlberg, Fred N. Teumac