Abstract:
In alternative embodiments, provided are methods and processes for the removal of cadmium (Cd) from wet-process phosphoric acid that may contain Cd, including excessive amounts of Cd. The process developed is based on the application of commercially available ion exchange resins with the application of Continuous Ion Exchange (CIX) technology. In alternative embodiments, provided are processes and methods for the recovery and/or the removal of cadmium from wet-process phosphoric acid using a continuous ion exchange approach. In alternative embodiments, use of processes and methods as provided herein allows for the reduction of cadmium metal contaminants with minimal phosphate losses and dilution in order to produce a phosphoric acid that is suitable for the production of fertilizers and phosphoric acid products, such as world-class diammonium phosphate fertilizer (DAP), merchant-grade phosphoric acid, super-phosphoric acid, and other phosphoric acid products.
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 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:
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.