Abstract: A method of adsorbing and separating a heavy metal element by using a tannin adsorbent comprising:(a) adjusting the pH of a solution containing a plurality of heavy metal elements to a predetermined pH;(b) contacting the adsorbent with the solution in which the pH thereof is adjusted;(c) adjusting the pH of the solution contacted with the adsorbent to a pH different from the predetermined pH; and(d) contacting the solution in which the pH thereof is adjusted at the step (d) with the adsorbent prepared at the step (a).According to the inventive method, all of the heavy metal elements can be efficiently separated and adsorbed by using a tannin adsorbent from a solution containing a number of heavy metal elements. A method of regenerating a tannin adsorbent are also disclosed.

Abstract: Technetium is separated from radio-contaminated metal in a three-step process. The contaminated metal is dissolved in an acid solution; the technetium, present in the resultant solution as pertechnetate ions, is quantitatively reduced to its metallic state through a metal displacement (cementation) reaction with a base metal of lower reduction potential; and the desired metal is electrolytically recovered from the solution, substantially free from technetium contamination.

Abstract: A process for recovering metal and acid values from a source material containing metallic fluorides comprises digesting the source material in sulfuric acid to form a slurry, separating a fluoride containing solid phase and a metal containing first liquid phase. The solid phase is subjected to pyrohydrolysis, sulfuric and hydrofluoric acids are recovered, and the first liquid phase is processed to recover the metal values by solvent extraction or ion exchanges. The tantalum values are extracted from the first liquid aqueous phase by a water immiscible organic extractant such as methylisobutyl ketone to form a first liquid organic phase containing tantalum and a second liquid aqueous phase. The tantalum is stripped from the first organic phase using water. The process includes the additional steps of heating the separated solid phase from about ambient temperature to an elevated temperature in the presence of water vapor to evolve sulfuric acid and render the gangue chemically inert.

Abstract: Environmental pollution stemming from the industrial discharge and/or storage of water-soluble thorium compounds is avoided by converting same into essentially innocuous water-insoluble thorium phosphates, notably orthorhombic thorium phosphates, by (i) reacting such water-soluble thorium compounds, e.g., the nitrates and/or chlorides, with a base, for example aqueous ammonia, in an aqueous reaction medium, to precipitate a thorium hydroxide therein, (ii) next reacting the precipitate thus formed with a phosphating compound, e.g., phosphoric acid or a soluble phosphate salt, also in an aqueous reaction medium, to precipitate a thorium phosphate therein, and then (iii) separating such thorium phosphate precipitate.

Abstract: Process for obtaining fritted oxide pellets of the MxOy type for nuclear fuels from solutions of soluble salts of the element or elements M, involving stage of precipitating the elements M by hydrogen peroxide in an acid medium. During this precipitation, there is an instantaneous dispersion of one of the reagents (solution of salts or peroxide) in the other, in order to obtain a homogenous mixture and an also instantaneous precipitation of the nuclei in a continuous liquid phase confined in an enclosure having minimum dimensions, the mother liquors being rapidly exhausted. The process makes it possible to obtain sintered pellets whose density exceeds 96% of the theoretical density.

Abstract: The process for recovering boron values and fluorine values from an acidic aqueous feed liquor containing substantial fluoroborate moieties, including contacting the feed liquor with basic material to adjust the pH thereof to above about 7.0 and provide a first clarified liquor containing the fluoroborate moieties, and contacting the first clarified liquor at elevated temperature with sufficient cation reactant selected from Al(OH).sub.3 or Al.sub.2 (SO.sub.4).sub.3 to precipitate substantially all of the fluorine values as an aluminum fluoride compound and provide a second clarified liquor containing the boron values as boric acid.

Abstract: Solutions such as for example drinking water, ground water and extracting solutions contaminated with heavy metals and radioactive species, singly or in combination, are treated by first treating the contaminated solution with silicate and ammonium hydroxide solution precipitants. Then the contaminated solution is separately treated with an acid which gels, polymerizes and/or precipitates the contaminant-containing silica matrix to form an easily dewaterable and separable solid. The solid contaminants are readily removed from the cleansed solution by filtration means. The process utilizes a novel combination of steps which maximizes contaminant removal, minimizes waste volume, and produces a treatable waste solid. The preferred precipitants are sodium silicate, and ammonium hydroxide. The preferred mineral acid is hydrochloric acid.

Abstract: Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described.

Abstract: A method for removing uranium from uranium contaminated water involves adding uranium reducing microorganisms and an electron donor to uranium contaminated water to reduce U(VI) in the uranium contaminated water to U(IV) which in turn forms a UO.sub.2 precipitate The UO.sub.2 precipitate is then separated from the contaminated water.

Abstract: A process for decontaminating radioactive material comprises the step of contacting the material with a dissolving composition to dissolve the contaminants in the material, said composition comprising a dilute solution of about 0.05 molar ethylene diamine tetraacetic acid, about 0.1 molar carbonate, about 10 grams per liter hydrogen peroxide and an effective amount of sodium hydroxide to adjust the pH of the composition to a pH from about 9 to about 11. Also included are the steps of separating the dissolving composition containing the dissolved contaminants from the contacted material and recovering dissolved contaminants from the dissolving composition that has been separated from the material. A composition for dissolving radioactive contaminants in a material, comprising a dilute solution having a basic pH and effective amounts of a chelating agent and a carbonate sufficient to dissolve radioactive contaminants is also provided.

Abstract: The process for converting water insoluble, hazardous materials of high mineral content containing, e.g.

Abstract: A process for recovering the chelating or complexing agents, particularly ethylenediaminetetraacetic (EDTA), used in chemical cleaning and decontamination operations performed to clean steam generators, especially nuclear powered steam generators, is provided. The EDTA, metal and radionuclide-containing aqueous waste stream is, optionally, first treated to remove the metals and radionuclides. The pH of the resulting liquor is then adjusted to less than 2.0, causing the precipitation of acid EDTA. The solid acid EDTA is recovered for reuse or disposal, as desired. The remaining liquid is treated as required to permit environmental disposal. Removal of the metals and radionuclides can be by sulfide precipitation or ion exchange and may be conducted before or after precipitation of the acid EDTA.

Abstract: A method of concentrating a plutonium nitrate solution comprising the steps of cooling the plutonium nitrate solution to a temperature of -60.degree. to -40.degree. C. to produce a frozen matter comprising water and nitric acid, and filtering the thus produced frozen matter to recover a concentrated plutonium nitrate solution as a filtrate.

Abstract: Magnesium is separated from magnesium slag containing radioactive thorium and its daughters by solubilizing magnesium from magnesium slurry using carbon dioxide and separating magnesium from magnesium slurry containing thorium and its daughters by filtering. The process concentrates the radioactive thorium and its radioactive daughters from the magnesium slag and reduces the volume of the radioactive waste that requires disposal.

Abstract: Technetium is separated from nickel by electro-refining contaminated nickel. Electrorefining controls the electrolyte solution oxidation potential to selectively reduce the technetium from the metallic feedstock solution from Tc(VII) to Tc(IV) forcing it to report to the anodic slimes and thereby preventing it from reporting to the cathodic metal product. This method eliminates the need for peripheral decontamination processes such as solvent extraction to remove the technetium prior to nickel electrorefining. These methods are particularly useful for remediating nickel contaminated by radio-contaminants such as technetium and actinides.

Abstract: A process of preparing an actinide compound of the formula An.sub.x Z.sub.y wherein An is an actinide metal atom selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, x is selected from the group consisting of one, two or three, Z is a main group element atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur and y is selected from the group consisting of one, two, three or four, by admixing an actinide organometallic precursor wherein said actinide is selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, a suitable solvent and a protic Lewis base selected from the group consisting of ammonia, phosphine, hydrogen sulfide and water, at temperatures and for time sufficient to form an intermediate actinide complex, heating said intermediate actinide complex at temperatures and for time sufficient to form the actinide compound, and a process of depositing a thin film of such an actinide compound, e.g.

Abstract: A method of separating uranium and plutonium from a mixed solution containing uranium nitrate and plutonium nitrate comprises cooling the mixed solution to a temperature ranging from -40.degree. to -20.degree. C. to thereby selectively precipitate uranyl nitrate. The precipitated uranyl nitrate is separated from the solution while leaving plutonium nitrate to remain in the solution.

Abstract: There is disclosed a waste treatment process for alkaline waste liquid in which substances to be removed exist in ionic and colloidal states. In the process, powdered tannin is added to the waste liquid to produce solid substance of the tannin and to capture the substances to be removed on the solid substance. Then, the waste liquid is subjected to filtration to thereby separate the solid substance including the substances to be removed.

Abstract: A process of converting an actinide metal such as thorium, uranium, or plnium to an actinide oxide material by admixing the actinide metal in an aqueous medium with a hypochlorite as an oxidizing agent for sufficient time to form the actinide oxide material and recovering the actinide oxide material is provided together with a low temperature process of preparing an actinide oxide nitrate such as uranyl nitrte. Additionally, a composition of matter comprising the reaction product of uranium metal and sodium hypochlorite is provided, the reaction product being an essentially insoluble uranium oxide material suitable for disposal or long term storage.

Abstract: A method and means for continuous precipitation of granular uranium peroxide. The reaction vessel and agitation method practiced in it avoid filter plugging and caking problems.

Abstract: A method for separating the isomers of a crown ether compound and making it possible to recover in particular the pure cis-syn-cis isomer from DCH 18C6 includes:a) dissolving in an organic solvent a mixture of the isomers of said crown compound including the cis-anti-cis isomer and the cis-syn-cis isomer,b) adding uranyl nitrate to the solution obtained in stage a) in sufficient quantities so that virtually all of the isomers, except the cis-syn-cis isomer, are precipitated in the form of complexes with the uranyl nitrate,c) separating the formed precipitate,d) recovering the cis-syn-cis isomer from the solution, ande) recovering the cis-anti-cis isomer from the precipitate.

Abstract: Sodium silicate (waterglass) is added to a waste process stream containing metal to form a waterglass sludge containing the metal contaminants. The waterglass sludge matrixed with the metal is removed from the stream. Thereafter, a caustic is added to the separated waterglass sludge which dissolves the sodium silicate, leaving a metal solid in suspension. The sodium silicate solution is filtered off and recycled for use in the waterglass precipitation process. The metal solid remains and concentrated acid is added to form a metallic acid solution which is substantially free of silicates. This solution may then be treated by solvent extraction or other means to recover the metal. The process provides substantial metal recovery from the process waste stream and eliminates the need for burial of the waste, thereby eliminating burial costs.

Abstract: A process for removing metal salts from an H.sub.4 EDTA precipitate by esterification with an esterification reagent to produce an esterification mixture comprising a solid metal salt an EDTA ester and thereafter separating the solid metal salt from the esterification mixture.

Abstract: A process of treating water to remove transuranic elements contained therein by adjusting the pH of a transuranic element-containing water source to within the range of about 6.5 to about 14.0, admixing the water source with an alkali or alkaline earth ferrate in an amount sufficient to form a precipitate within the water source, the amount of ferrate effective to reduce the transuranic element concentration in the water source, permitting the precipitate in the admixture to separate and thereby yield a supernatant liquid having a reduced transuranic element concentration, and separating the supernatant liquid having the reduced transuranic element concentration from the admixture is provided. Additionally, a water soluble salt, e.g., a zirconium salt, can be added with the alkali or alkaline earth ferrate in the process to provide greater removal efficiencies. A composition of matter including an alkali or alkaline earth ferrate and a water soluble salt, e.g., a zirconium salt, is also provided.

Abstract: A high-level radioactive waste liquid, produced in a reprocessing plant, is treated by a freeze-drying step. A low-level radioactive waste liquid containing water, nitric acid and nuclides is obtained from the sublimate of the freeze-drying step. Fission products, actinides, corrosion products (iron, chromium, nickel, etc.), sodium nitrate and sodium hydroxide, not sublimated, are separated as a residue. An alkaline solution such as sodium hydroxide solution is added to the residue to dissolve sodium nitrate and sodium hydroxide. The dissolved nitrate and hydroxide are then separated from the residue containing fission products and the corrosion products.

Abstract: Rare earth hydroxides are recovered from the rare earth ores, e.g., monazite, xenotime and/or bastnasite, by treating the ore with an aqueous solution of an alkali metal hydroxide, under agitation and essentially constant pressure, at a temperature of from about 100.degree. to 220.degree. C., and wherein the ratio by weight of alkali metal hydroxide/ore ranges from about 1.4 to 0.5, e.g., a weight ratio of sodium hydroxide/ore of from about 1 to 0.5, or a weight ratio of potassium hydroxide/ore of from about 1.4 to 0.7.

Abstract: The separation of uranium, iron and scandium is achieved by the following process wherein a material containing these values is dissolved in mineral acid to form an aqueous solution, thereafter, an iminodiacetic acid cationic ion exchange resin is used to retain a major portion of the scandium and uranium. A raffinate containing the iron is formed. The ion exchange resin having said scandium and uranium retained thereon is rinsed with a dilute acid to remove residual metals other than scandium and uranium. The resin is eluted with an aqueous solution of an organic chelating acid to remove a major portion of the scandium from said resin and to form an aqueous solution containing scandium. The resin is then eluted with an aqueous solution of a mineral acid to remove a major portion of the uranium from the resin to form an aqueous solution containing the uranium. The scandium and uranium are recovered as solids.

Abstract: Thorium and rare earth values are separated from a fluoride concentrate thereof, by decomposing such concentrate with aqueous sodium hydroxide under conditions such that the amount of sodium hydroxide is at least 1.4 times the stoichiometric amount and the initial sodium hydroxide/water ratio in the medium of decomposition ranges from 1 to 40% by weight, whereby a precipitate of thorium hydroxide and rare earth hydroxides is produced, together with a solution of sodium fluoride, and then separating the NaF solution therefrom.

Abstract: A process for preparing uranium tetrafluoride by reacting a uranous solution with a hydrofluoric acid solution in a fluorination precipitation tank is provided. A cylindrical inner tube having upper and lower ends opened is disposed in the tank in the longitudinal direction thereof. An agitator is arranged within the inner tube to generate a descending or ascending stream inside the inner tube and a ascending or descending stream outside the inner tube, thereby producing a circulation of reaction liquor in the tank. The uranous solution and the hydrofluoric acid solution are introduced into the tank from the upper part thereof and the produced uranium tetrafluoride crystals are withdrawn from the lower part of the tank together with a part of the reaction mother liquor. The amount of the hydrofluoric acid solution added to the uranous solution is adjusted so that the fluorine concentration in the reaction mother liquor in the tank is maintained at 2 to 4 g/l.

Abstract: The invention has as its object a process for the purification of a uranium solution which is contaminated by zirconium. This process consists of bringing the pH of the solution to a value of 1 to 3, then adjusting the pH of the said solution to, and maintaining it at a value of 2.5 to 3 while raising the temperature to a value of around 30.degree. to around 60.degree. C. for a period sufficiently long that there occurs a selective precipitation of at least 70% of the zirconium while the uranium remains in the dissolved state.

Abstract: This invention can treat a uranium-containing solution of high or low concentration and/or the waste generated from uranium conversion processes, etc. It is characterized by the use of acorns, nuts of oak tree, which can be easily obtained in our botanical system. By coprecipitating the uranium or other heavy metal elements with the extract of acorns, this invention can not only recover the uranium of other heavy metal elements but also can reduce them before being discharged to the environmental radioactivity level.

Abstract: Improvement to the separation and recovery of solids from liqiuds containing them, and using a ionic flotation process, implementing an installation characterized in that it comprises at least a vat (1) for pretreating the solution to be treated for the insolubilization of the solid to be recovered and the formation of a suspension maintained under stirring conditions (stirrer 2), at least a flotation cell (5) supplied with said suspension, at least a device (4) provided between said vat (1) and said flotation cell (5) adapted to generate within the cell a rising non-turbulent stream intended to convey the desired solid towards the surface of said suspension while maintaining at said surface a calm area for the accumulation of said solid and at least one means for the recovery of said solid (6-7).

Abstract: The present invention relates to a method and an apparatus for producing a waste package of radioactive waste containing particles of radioactive waste material of low modulus of elasticity, particles of radioactive waste material of high modulus of elasticity, and a solidifying agent in which the particles of radioactive waste material of low modulus of elasticity and the particles of radioactive waste material of high modulus of elasticity are fixed in an almost uniformly dispersed state. According to this invention, the radioactive waste generated from nuclear power plants can be greatly reduced in volume and also a waste package of radioactive waste with high strength and excellent water resistance can be obtained.

Abstract: The process of the present invention comprises adding an alkaline earth metal hydroxide such as barium hydroxide to a radioactive liquid waste containing sodium sulfate as the main component to convert the latter into an insoluble alkaline earth metal salt such as barium sulfate, adding silicic acid to by-product sodium hydroxide to prepare water glass and solidifying the radioactive insoluble alkaline earth metal salt with the water glass. According to this process, exudation of radioactive substances from the solid can be prevented and the solid having a high durability can be obtained at a low cost.

Abstract: A process for separately recovering uranium and hydrofluoric acid from a waste liquor containing uranium and fluorine comprises a neutralizing precipitation step wherein a magnesium compound is added to the waste liquor containing uranium and fluorine to form a precipitate and the thus formed precipitate is then separated; a distillation step wherein an aqueous solution of sulfuric acid is added to the precipitate separated in said neutralizing precipitation step to dissolve the precipitate and the thus formed solution is then distilled to recover hydrofluoric acid as a distillate; and a uranium recovery step wherein uranium is recovered from a residue produced by said distillation step.

Abstract: A method for treating a radioactive metal-containing natural water or liquid such as a radioactive metal-containing wastewater stream, an oil containing one or more radioactive metals, or other nuclear metal-bearing liquid by contacting the radioactive heavy metal-containing liquid with a water-in-soluble carboxylated cellulose to separate the heavy metals from the liquid. The process has been found to be unexpectedly effective on radioactive wastewaters or any other liquid containing one or more radioactive heavy metal ions such as U, Ce, Sr, Ru, Ra, Np, Tc, as well as radioactive ions such as I.

Abstract: Process for the batch purification of uranium recovered in a reprocessing process, after a first separation of impurities, in which for each batch an aqueous, nitric acid uranyl-nitrate solution (UNH original solution), which still contains residual amounts of impurities, is cooled to crystallize out purified UO.sub.2 (NO.sub.3).sub.2 .multidot.6H.sub.2 O (UNH) from the solution and the resulting crystals are separated out of their mother liquor and washed. The original solution is adjusted to a specified uranium concentration and the adjusted solution is cooled to below 0.degree. C. to bring about the crystallization. The duration between starting and ending the crystallization is held between 0.1 and 10 hours. The amount of the UNH crystals which is crystallized out corresponds to at least about 80 weight % of the uranium content introduced. The ratio of the volume of the crystals formed to the volume of the remaining mother liquor is not larger than 0.5.

Abstract: The invention relates to a process for decontaminating and adjusting the pH of uraniferous solutions to render them compatible with the natural environment into which they may be discharged. This process is characterized in that the solutions to be treated having a natural pH from about 2.5 to about 6.5 and containing from about 1 to about 100 mg/l of uranium, are supplemented with an aluminum salt, such as sodium aluminate, in a sufficient amount for the final pH to be from about 5.5 to about 8.5 and for there to be precipitation, coagulation and adsorption of about 90% of the uranium initially contained in the solution and for the uranium content remaining in the final solution obtained to be equal to or less than about 1.8 mg/l.

Abstract: A process for selectively separating plutonium from uranium and other metals is disclosed wherein, in order to precipitate and remove the pertaining complexes, use is made of a sufficient quantity of a cationic compound containing at least one group adapted to assert affinity to polar surfaces and containing a radical which has little affinity to water, e.g. surface active agents and the like, and use is made of the capability of Pu.sup.4+ and U.sup.4+ to form nitrato-complexes and of the capability of Pu.sup.4+ and UO.sub.2.sup.2+ to form sulfato-complexes.

Abstract: Uranium is recovered as UF.sub.4 from phosphate solutions. The uranium is reduced to the tetravalent state and extracted with an organic extractant. The uranium is recovered as UF.sub.4 by reextracting with an aqueous HF solution which includes UF.sub.4 in suspension for improved reextraction.

Abstract: The present invention is directed to a process to improve the suspended solids removal by the filter cloth used in the clarification of leached uranium ore, comprising contacting the filter cloth with an effective amount of an acrylamide polymer.

Abstract: A method of decontaminating mixtures of radioactively contaminated water and radioactively contaminated water-immiscible organic liquids to produce a decontaminated organic liquid which can be disposed of in a conventional manner.

Abstract: Process for the selective separation of uranium in carbonated aqueous solution from soluble impurities including in particular at least one of the elements zirconium and/or hafnium and/or molybdenum, thereby making it possible to produce a uraniferous liquor in a greatly improved state of purity, comprising precipitation of the zirconium and/or hafnium by introducing an alkali metal hydroxide, then separation of the zirconiferous precipitate which possibly contains hafnium and/or molybdenum from the resulting uraniferous solution with its reduced impurities content, which still possibly contains molybdenum, which is characterized in that in order to increase the removal of zirconium and/or hafnium and/or molybdenum, the uraniferous carbonated aqueous solution is treated by means of a dilute alkaline aqueous solution containing at most 17 g/l of at least one alkali metal hydroxide expressed in respect of OH.sup.

Abstract: Radioactive waste is first converted into hardly water-soluble powder (including a water-insoluble powder) and then solidified with a hydraulic solidifier in a solidification vessel. The radioactive waste may be powdered (including granulated and encapsulated) by incorporating the radioactive waste with a substance which is capable of reacting with the water-soluble salt contained in the radioactive waste to form a hardly water-soluble salt (including a water-insoluble salt) and then powdering the mixture with drying, or by powdering the radioactive waste with drying, granulating the powder with drying and then microencapsulating the granules with a hardly water-soluble substance (including water-insoluble substance). The hardly water-soluble salts are preferably calcium salts, and the additives are preferably calcium hydroxide solution or solvent of combination of dichloromethane solution and hexane.

Abstract: The invention concerns the recovery of heavy metals from concentrated solutions.The process comprises complexing the metals with an organophosphorous complexing agent and recovering the metallic complex by sedimentation, filtration, flotation and the like.The process can be used to recover uranium and rare earths from phosphoric acid solutions.

Abstract: In the process for treating irradiated nuclear fuel to effect separation of uranium plutonium other higher actinides, and fission products, in which nitric acid treatment, followed by solvent extraction, then backwashing the reduction of tetra- and hexa-valent plutonium to the tri-valent form, then a second solvent extraction by which the tri-valent plutonium remains in the aqueous phase while uranium goes into the solvent phase, the reduction step is performed by hydrazine with or without tetra-valent uranium nitrate and catalyzed by technetium in the tetra-valent form with or without technetium in one or more higher valency states. The technetium can be present in the system as an irradiation product or be added to the process stream in a combined form.

Abstract: The invention relates to a method for recovering rare metals from the combustion residues of various coals, in particular brown coals. The recovery is performed by digestion, more particularly by aqueous and/or dilute alkaline and/or dilute acidic digestion, where two or three of these steps can be combined in any desired order or they may be carried out separately. During digestion the concentration of the solution is monitored and the subsequent digestion steps are terminated at a desired concentration. The solid and liquid phase are then separated and the rare metals are isolated from the liquid phase while the solid phase, optionally after neutralization and/or washing can be utilized for example as a source of energy.

Abstract: A process for the recovery of the uranium present in phosphoric acid produced by a wet process in (A) by means of a suitable solvent (L.sub.9), which is carried out after separation of the gypsum in (B) formed in the attack operation, and elimination of the solid materials which are still in suspension, characterized in that, in order to avoid the formation of dross in the course of the operation of extracting the uranium which is previously reduced in (D), the step of eliminating the solid materials which are still in suspension is effected by a final solid-liquid separation operation in (C) and/or in (E), prior to extraction of the uranium in (F), in the presence of an added fraction of gypsum (S.sub.22) and/or (S.sub.23) resulting from the production of H.sub.3 PO.sub.4.

Abstract: A process for denitrating aqueous, nitric acid and salt containing waste solutions in which actinides are present, with simultaneous separation of the actinides, comprises agitating the waste solution at room temperature with diethyl oxalate and heating the resulting suspension to at least 75.degree. C.

Abstract: A process for selectively separating plutonium from uranium and other metals is disclosed wherein, in order to precipitate and remove the pertaining complexes, use is made of a sufficient quantity of a cationic compound containing at least one group adapted to assert affinity to polar surfaces and containing a radical which has little affinity to water, e.g. surface active agents and the like, and use is made of the capability of Pu.sup.4+ and U.sup.4+ to form nitrato-complexes and of the capability of Pu.sup.4+ and UO.sub.2.sup.2+ to form sulfato-complexes.