Described are methods for the recovery of uranium from uranium hexafluoride dissolved directly into ionic liquids.

The present invention concerns a process for producing calcium carbonate from a calcium-containing alkaline slag material, the process containing the steps of extracting the alkaline slag material in a series of extraction steps, including at least 2 extraction steps, using extraction solvent(s) containing salt in an aqueous solution, whereby a calcium-containing filtrate and a residual slag is formed in each extraction step, separating the residual slag from the filtrate after each extraction step, carrying each residual slag to the following extraction in the series of extractions, to be used as raw material in said following extraction, and discarding the residual slag separated from the last extraction, carrying each filtrate to the previous extraction in the series of extractions, to be used as extraction solvent in said previous extraction, and carrying the first filtrate, separated from the first extraction step, to a carbonating step, carbonating calcium as calcium carbonate from the first filtrate, the first filtrate also used as the carbonation solvent, and using a carbonation gas, whereby calcium carbonate precipitates, separating and recovering the calcium carbonate from the remaining carbonation solvent, and recycling the remaining carbonation solvent to the last extraction step in the series of extraction steps, to be used as extraction solvent.

The-use of carbamides as extractants for fully or partially separating uranium(VI) from plutonium(IV) in an aqueous solution obtained by dissolving a spent nuclear fuel in nitric acid, by method of liquid-liquid extraction, without carrying out any reduction of the plutonium(IV) to plutonium(III). The invention also relates to new carbamides. Uses are the processing of spent nuclear fuels based on uranium (especially uranium oxides—UOX) or uranium and plutonium (especially mixed uranium and plutonium oxides—MOX).

An integrated drying process and device for dry granulated slag and sludge. The process comprises the following steps: 1) slag ball mixing and soaking: high-temperature slag and steel balls are fully mixed and exchange heat therebetween, the high-temperature slag is cooled because the heat thereof is quickly absorbed by the steel balls and is crushed to form granular slag, and the temperature of the steel balls rises because the steel balls absorb the heat of the high-temperature slag; and 2) sludge drying: the high-temperature steel balls are conveyed to a sludge drying device to be mixed with injected sludge, the sludge is dried, the steel balls are separated from the sludge when the water content of the sludge reaches a set value, and the steel balls and the sludge are separately discharged. In the present invention, high-temperature slag waste heat is used for heating steel balls, and sludge is dried by means of the heated steel balls, thus achieving the cooperative treatment of slag cooling, granulation and sludge drying, solving two difficult problems of slag cooling and sludge drying, and greatly increasing the waste heat recycling rate of high-temperature slag.

Methods and systems for separation of thorium from uranium and their decay products are provided. The method comprises combining a nuclear fuel feedstock comprising thorium and uranium with a first acid to form a first solution. The first solution is contacted an ion exchange resin that is selective for thorium or uranium. The thorium or uranium is at least partially removed from the first solution by binding the thorium or uranium to the ion exchange resin thereby forming a second solution. The second solution is combined with oxalic acid to precipitate uranium or thorium from the second solution to form a precipitate. The precipitate is separated from the second solution.

A material (e.g., an alloy) comprises molybdenum, rhenium, and at least one element selected from the group consisting of tellurium, iodine, selenium, chromium, nickel, copper, titanium, zirconium, tungsten, vanadium, and niobium. Methods of forming the material (e.g., the alloy) comprise mixing molybdenum powder, rhenium powder, and a powder comprising at least one element selected from the group consisting of tellurium, iodine, selenium, chromium, nickel, copper, titanium, zirconium, tungsten, vanadium, and niobium. The mixed powders may be coalesced to form the material (e.g., the alloy).

A conversion process for converting uranium hexafluoride into uranium dioxide includes the steps of hydrolysis of UF6 to uranium oxyfluoride (UO.sub.2F.sub.2) in a hydrolysis reactor (4) by reaction between gaseous UF6 and dry water vapour injected into the reactor (4), pyrohydrolysis of UO.sub.2F.sub.2 to UO.sub.2 in a pyrohydrolysis furnace (6) by reacting UO.sub.2F.sub.2 with dry steam and gaseous hydrogen (H.sub.2) injected into the furnace (6), extracting excess gas in the reactor (4) via a collecting device (50) comprising several filters (52), periodically cleaning the filters (52) by injecting a neutral gas into the filters (52) from the outside to the inside of the reactor (4) to remove powder stuck on the filters (52), and measuring the relative pressure in the reactor (4). The conversion method further includes carrying out point cleaning of the filters (52) when the relative pressure in the reactor (4) exceeds a predetermined point cleaning threshold.

Systems and methods are described in which spent pickle liquor from metal cleaning processes is utilized to regenerate a lixiviant used to recover valuable metals from industrial waste and other sources. The spent pickle liquor is neutralized and solvated metals in the spent pickle liquor are precipitated in this process. When the industrial waste is slag from a metal refining process a partially closed metal production process can be implemented, where spent pickle liquor from cleaning of the refined metal is used to regenerate a lixiviant used to recover a different, valuable metal from a waste slag of the process, with precipitated salts from the lixiviant regeneration being returned as a raw material in the metal refining process. As a result waste streams from these processes are dramatically reduced or eliminated.

A waste recycling system with an automated dumpster includes a main body and the main body includes a main control module. The main control module includes a main control unit, and is electrically connected to a dumpster module. The dumpster module includes a dumpster and the dumpster includes a sub-control module. The sub-control module includes a sub-control unit. The sub-control unit is electrically connected to a power unit and a scanning unit. The power unit is used to drive the dumpster and the scanning unit is disposed at the front end of the dumpster to receive signals. The sub-control unit also includes guiding units. The guiding unit is disposed on the transporting path of the dumpster. By the scanning unit, the scanned signal is transmitted back to the sub-control unit to control the dumpster moving automatically.

A method of direct oxide reduction includes forming a molten salt electrolyte in an electrochemical cell, disposing at least one metal oxide in the electrochemical cell, disposing a counter electrode comprising a material selected from the group consisting of osmium, ruthenium, rhodium, iridium, palladium, platinum, silver, gold, lithium iridate, lithium ruthenate, a lithium rhodate, a lithium tin oxygen compound, a lithium manganese compound, strontium ruthenium ternary compounds, calcium iridate, strontium iridate, calcium platinate, strontium platinate, magnesium ruthenate, magnesium iridate, sodium ruthenate, sodium iridate, potassium iridate, and potassium ruthenate in the electrochemical cell, and applying a current between the counter electrode and the at least one metal oxide to reduce the at least one metal oxide. Related methods of direct oxide reduction and related electrochemical cells are also disclosed.