Other

The Catholic University of America

Consolidated Edison Company of New York, Inc.

University System of Maryland

Pedro B. Macedo

Theodore Aaron Litovitz

Aaron Barkatt

Pedro B Macedo

Marta Gmurczyk

Hamid Hojaji

Mohamad Al-Sheikhly

Herbert G Sutter

Miriam Lemus

Ewa Labuda

Chanel Tissot

Stephanie A Olszowka

Galina Cherepakhov

Donna M Wilder

Complexing or chelating agents that offer strong, selective bonding with uranium as well as a broad pH range of effectiveness, specifically including the pH range around 8.2, together with the acrylic double bonds required for radiation-induced grafting on polymers to remove uranium from a solution such as seawater. The novel adsorbing species are phosphorus-containing molecules, in particular organic phosphates, phosphonates and phosphoric acids. Organic phosphorus compounds, for example, organic phosphates, phosphonates, and phosphoric acids, are attached to polymer fibers to form fibers, fiber fabrics or membranes that are effective, or show activity, in uranium adsorption.

Polymers grafted with organic phosphorous compounds for extracting uranium from solutions

Organic materials are mixed with metal oxide, such as hydrated metal oxides, prior to or during heat treatments in aerated or oxygenated environments to stabilize thermal decomposition or incineration of the organic materials and to suppress the emission of volatile, hazardous organic compounds. The organic materials may be ion exchange resins and polymeric sorbents, for example, and include contaminated materials such as hazardous wastes. The hydrated metal oxides may be hydrated ferric oxide, hydrated aluminum oxide or hydrated titania oxide, for examples. Ferrihydrite is preferred. The heat treatment may be a preparation for a waste disposal process, such as immobilization in ferric oxide, cement, concrete, a polymer, bitumen or glass, for example. Immobilization processes in ferric oxide are also discussed, including the use of additives such as magnesium oxide, ammonium dihydrogen phosphate and phosphoric acid, enabling consolidation at room temperature and pressures less than 15,000 psi.

Thermal treatment and immobilization processes for organic materials

Processes for immobilizing solid contaminated materials, such as radioactive species, hazardous species, or combinations of both radioactive and hazardous species, comprise mixing the contaminated materials with hydrated ferric oxides, and then pressing the mixture at a temperature of at least about 150.degree. C. and gradually removing a large part of the water while under pressure to produce a solid composition. The water content of the mixture is adjusted if necessary. Contaminated materials dissolved or suspended in an aqueous solution can be immobilized by precipitating hydrated ferric oxide in the solution, and adjusting the water content and pressing, as above. In another process in accordance with the present invention, hydrated ferric oxides are deposited on metal surfaces. The deposited ferric oxide is pressed to produce a solid coating adhered to the surface, to retard corrosion. A ceramic body of ferric oxide composition may also be made in accordance with the present invention.

Immobilization of radioactive and hazardous contaminants and protection

A process for the decontamination of solid surfaces contaminated with radioactive or heavy metal species using a solution based on one or more non-persistent complexing agents, or for the chemical cleaning of steam generator sludge using such a solution, or for removing radioactive or heavy metal species from a solution using a combination of a one or more non-persistent complexing agents and a solid support, followed in each case by thermal or thermal-chemical treatment to decompose said non-persistent complexing agent. The preferred non-persistent complexing agents are hydroxamic acids, and the most preferred is acetohydroxamic acid.

Removal of radioactive or heavy metal contaminants by means of

Improved superconducting materials with high maximum magnetization, remanent magnetization and diamagnetic susceptibility can be made by enriching the base Y-Ba-Cu-O composition, Y:Ba:Cu=1:2:3, with respect to Y, or adding other trivalent or pentavalent elements (e.g. rare earths, Nb) to this composition. The mixed oxide materials are heated to melt a substantial fraction of their weight, quenched to a low temperature, re-heated to a temperature lower than the one initially used to effect melting, and annealed by slow cooling under air or oxygen.

Method for the formation of high temperature semiconductors

Compositions comprising carbon-based supports and containing heteropolycyclic compounds such as bipyridyl, phenanthroline or derivatives thereof are used in separation of dissolved late transition metals such as Fe, Co, Ni and Cu from solutions, in particular when such solutions contain high concentrations of other dissolved metals such as Zr, Hf, La, Al and Ba. Such compositions are also used to separate late transition metals such as Pt group metals from each other.

Supported heteropolycyclic compounds in the separation and removal of

A method for separating and purifying cations by ion exchange with regenerable porous glass. More specifically, the method is for decontaminating toxic waste streams such as a radioactive waste streams and concentrating the radioactive cations contained therein which comprises passage of the waste stream through an ion exchange medium of porous silicate glass or silica gel. In one embodiment, a liquid nuclear waste stream is passed through an ion exchange column containing porous silicate glass or silica gel having a plurality of .tbd.Si--O--Z groups wherein Z represents a non-radioactive cation (hydrogen, alkali metals, Group Ib metals and ammonium cations, and mixtures thereof) to displace the non-radioactive cations of the silicate glass or silica gel by the radioactive cations of the waste stream. Thereafter, the ion exchange medium is contacted with an aqueous solution of an acid to strip the radioactive cations therefrom and the stripped ion exchange medium is regenerated. The stripped ion exchange medium can be regenerated by contacting it with an aqueous basic solution of an alkali metal or ammonium ion. Additional liquid radioactive waste is contacted with the regenerated ion exchange medium to decontaminate an additional volume of liquid waste.

Method of separating and purifying cations by ion exchange with

A composition comprising a support such as a porous silicate glass or silica gel or charcoal having interconnected pores and containing heavy metal cations of mercury, thallium, silver, platinum, palladium, lead or copper capable of forming a stable complex with an anion bonded to the support. The preferred heavy metal cation is a mercury cation. The composition is especially useful for removing radioactive iodine from liquid and gaseous waste streams.

Fixation of anionic materials with a complexing agent

A process for removing metal species from solution comprising passing the liquid over a composition comprising a support such as a porous silicate glass or silica gel or charcoal having interconnected pores and containing water soluble amine complexing agents absorbed on the support capable of forming a stable complex with the metal species. The preferred amine complexing agent is triethylenetetramine. The process is especially useful for removing radioactive cobalt from liquid waste streams.

Fixation of dissolved metal species with a complexing agent

A process for removing heavy alkali metal cations from solution comprising passing a liquid over a composition including a support such as charcoal having interconnected pores containing a tetra-aryl boron moiety associated with an ion exchangeable cation absorbed on the support capable of forming a stable compound with a heavy alkali metal cation.

Ion exchanger to separate heavy alkali metal ions

Silica-based chromatographic and reactive materials are disclosed with surfaces modified to contain or to be coated with oxides, hydrous oxides, hydroxides, carbonates or silicates of aluminum, iron, or other suitable metals such as zirconium or titanium. The materials exhibit good resistance to dissolution and resulting loss of activity or clogging. This good resistance is particularly evident even in the high pH region (above 8-9) and in the high temperature region (above 35.degree. C.) where the dissolution rates and solubilities of aluminosilicates and of trivalent iron oxides are much smaller than those of silica.

Process of using improved silica-based chromatographic supports

Silica is selectively removed from aqueous liquid containing a relatively large amount of borate (or boric acid) and a relatively small amount of silica using borate loaded alumina as the sorbant. The effluent can be passed through lithium loaded cation exchange resin to remove any dissolved aluminum.

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Silver Spring, MD, United States of America

Aaron Barkatt