Abstract:
In particular, in alternative embodiments, the invention provides for a method to recover silicofluoride and phosphate species from wastewaters, or barometric condenser waters, that are typically utilized in wet-process phosphoric acid facilities. The species are recovered via a continuous ion exchange approach that allows for economic recovery of the materials and especially with the silicofluoride component allows for the production of valuable industrial materials such as hydrofluoric acid and other fluoride salts as well as industrial-grade precipitated silica materials. Return of the treated waste water to the phos-acid plant allows for optimization of reagent usage.
Abstract:
The present invention relates to a continuous ion exchange methodology for production of ammonium-potassium polyphosphate solutions using agricultural grade phosphoric acid, anhydrous ammonia, and agricultural grade potassium chloride (ag potash) as primary feedstocks. The method is particularly applicable to the production of these low salt index, specialty liquid fertilizer solutions and allows for the use of less expensive ag- potash and impure phosphoric acid as the potassium and phosphate sources in order to produce the ammonium-potassium polyphosphate compounds, which are chloride free as a result of the ion exchange process.
Abstract:
In alternative embodiments, the invention provides processes and methods for the recovery, removal or extracting of, and subsequent purification of uranium from a wet- process phosphoric acid using a continuous ion exchange processing approach, where the uranium is recovered from a phosphoric acid, or a phos-acid feedstock using either a dual or a single stage extraction methodology. In both cases an intermediate ammonium uranyl-tricarbonate solution is formed. In alternative embodiments, in the dual cycle approach, this solution is contacted in a second continuous ion exchange system with a strong anion exchange resin then subsequently recovered as an acidic uranyl solution that is further treated to produce an intermediate uranyl peroxide compound which is ultimately calcined to produce the final uranium oxide product. In alternative embodiments, in the single cycle case, the intermediate ammonium uranyl-tricarbonate solution is evaporated to decompose the ammonium carbonate and produce an intermediate uranium carbonate/oxide solid material. These solids are digested in an acid medium, and then processed in the same manner as the secondary regeneration solution from the dual cycle process to produce an intermediate uranyl peroxide that is calcined to produce a final uranium oxide product.
Abstract:
In alternative embodiments, the invention provides processes and methods for extracting and recovering rare earth materials from a wet-process phosphoric acid using one or more continuous ion exchange resin systems. In alternative embodiments, the method is particularly suited for use in extracting and recovering multiple rare earth materials present in low concentrations contained in wet-process phosphoric acid.
Abstract:
In alternative embodiments, the invention provides processes and methods for the recovery or the removal of the so-called "Minor Elements" consisting of iron, aluminum and magnesium (expressed as oxides), from wet-process phosphoric acid using a continuous ion exchange approach. In alternative embodiments, use of processes and methods of the invention allows for the reduction of these Minor Elements with minimal phosphate losses and dilution in order to produce a phosphoric acid that is suitable for the production of fertilizer products such as world-class diammonium phosphate (DAP), merchant-grade phosphoric acid, superphosphoric acid, and other phosphoric acid products. Further, use of the invention would allow the use of lower grade phosphate rock or ore, which would greatly expand the potential phosphate rock reserve base for phosphate mining activities, and allow for better overall utilization of resources from a given developed mine site.