Abstract: In the manufacture of phosphoric acid from ore, the typical ore comprises minerals containing phosphorus and calcium along with varied amounts of other elements. Certain ores have substantial iron content which needs to be removed in order to produce quality phosphoric acid product. An improved method and associated chemical processing plant are disclosed for removing this iron. The method involves both reducing and adding oxalic acid to wet process phosphoric acid produced using an otherwise conventional manufacturing process. Iron oxalate precipitate is created which can then conveniently be separated therefrom.

Abstract: Processes for recovering an organic solvent extractant phase from a solid-stabilized emulsion formed in a hydrometallurgical solvent extraction circuit are disclosed. One such process includes mixing a de-emulsifier comprising an effective amount of a polymeric aggregating agent with the solid-stabilized emulsion, thereby separating the emulsion into its aqueous, organic, and solid phase components; and removing the organic solvent extractant phase from the other components, thereby recovering the organic solvent extractant phase from the solid-stabilized emulsion.

Abstract: An aluminum phosphate composition comprising aluminum phosphate, aluminum polyphosphate, aluminum metaphosphate, or a mixture thereof. The composition may be characterized by, when in powder form, having particles wherein some of the particles have at least one or more voids per particle. In addition, the composition is characterized by exhibiting two endothermic peaks in Differential Scanning Calorimetry between about 90 degrees to about 250 degrees Celsius. The composition is also characterized by, when in powder form, having a dispersibility of at least 0.025 grams per 1.0 gram of water. The composition is made by a process comprising contacting phosphoric acid with aluminum sulfate and an alkaline solution to produce an aluminum phosphate based product; and optionally calcining the aluminum phosphate, polyphosphate or metaphosphate based product at an elevated temperature. The composition is useful in paints and as a substitute for titanium dioxide.

Abstract: An aluminum phosphate or polyphosphate-based pigment product is made by a process comprising contacting phosphoric acid with aluminum sulfate and an alkaline solution to produce an aluminum phosphate based product; and optionally calcining the aluminum phosphate based product at an elevated temperature, wherein the process is substantially free of an organic acid. The aluminum phosphate or polyphosphate-based pigment is amorphous. The amorphous aluminum phosphate or polyphosphate characterized by a bulk density of less than 2.30 grams per cubic centimeter and a phosphorus to aluminum mole ratio of greater than 0.8. The composition is useful in paints and as a substitute for titanium dioxide.

Abstract: The invention relates to a process for the production of high purity phosphoric acid which has a very low content in antimony, and is suitable for food, pharmaceutical, or electronic industry.

Abstract: The invention relates to a process for the production of high purity phosphoric acid which has a very low content in antimony, and is suitable for food, pharmaceutical, or electronic industry.

Abstract: A method for etching phosphate ores includes a single-pass digesting of ores which P205 content is greater than 20% in weight by a hydrochloric aqueous acid solution having an HCI concentration less than 10% by weight with an etching solution formation and the separation of the insoluble solid phase and the aqueous phase of the etching solution. Preneutralization of the etching solution is accomplished by a neutralizing agent prior to the separation in such a way that the etching solution pH which is less than pH to which an important part of phosphate ions in solution precipitates in the form of calcium monohydrogen phosphate (DCP) is adjusted and in subsequently neutralizing the separated aqueous phase in such a way that a pure DCP is precipitated.

Abstract: A method of preparing a phosphoric acid salt which includes at least one attack on phosphate ore by an aqueous solution of hydrochloric acid, with the formation of an attack liquor, a first separation, in the attack liquor, between an insoluble solid phase and an aqueous phase, a neutralization of the separated aqueous phase by the addition of a calcium compound in order to form, with phosphate ions contained in this aqueous phase, a calcium phosphate insoluble in water, which precipitates, and a second separation, in the neutralized aqueous phase, between a liquid phase and a precipitated solid phase based on the calcium phosphate insoluble in water, wherein the attack on the phosphate ore includes dissolving the phosphate in the ore, the attack liquor containing this phosphate in the form of phosphate ions, and the solid phase separated from the attack liquor contains impurities and the aqueous phase separated from the attack liquor contains the phosphate ions thereof, chloride ions and calcium ions, this a

Abstract: A method for the production of phosphoric acid comprising a phosphate ore attack by a first aqueous chlorohydric acid solution, separation in the attack liquor between a solid insoluble phase containing impurities and a separate aqueous phase comprising phosphate ions in a solution, chloride ions and calcium ions, neutralization of said attack phase separated from the liquor by adding a calcium compound so that water-insoluble calcium phosphate can be formed with said phosphate ions, precipitating a separation in said neutralized aqueous phase comprising chloride ions and calcium ions in a solution and a solid precipitated phase based on said water-insoluble calcium phosphate, and solubilization of at least one part of the precipitated solid phase in a separated manner in a second aqueous chlorohydric acid solution, with formation of an aqueous solution containing phosphate ions, chloride ions and calcium ions to be extracted by an organic extractant in a liquid-liquid-type extraction.

Abstract: An improved process of extraction of uranium from phosphoric acid and in particular uranium VI from phosphoric acid especially strong phosphoric acid using a selective synergistic extractant mix of an organo-phosphorous acid and a neutral extraction agent. The process basically involves the steps of extraction comprising contacting said acid with a selective synergistic extractant system of di-nonyl phenyl phosphoric acid (DNPPA) and a neutral agent selected from di-butyl butyl phosphonate (DBBP) and tri-n-octyl phosphine oxide (TOPO); and recovering the uranium values from the loaded organic phase. The above process would provide for an improved process for recovery of uranium both from weak and strong phosphoric acids using a stable and relatively cheap extractant system. The process is directed to improved recovery of U-VI from phosphoric acid by way of a simple, industrially applicable and cost-effective process.

Abstract: A process for purification by multistage countercurrent extraction of wet-process phosphoric acid includes the steps of (a) preparing an aqueous phosphoric acid by decomposition of crude phosphates with sulfuric acid and prepurification thereof; (b) providing an organic solvent mixture consisting of one of (A) a water immiscible solvent and a fully water-miscible solvent or (B) a partially water-miscible solvent and a fully water-miscible solvent; (c) extracting water from the acid by contacting with the solvent mixture in a volumetric ratio of acid to solvent mixture of 1:1 to 1:10 at a temperature of 5 to 90° C.; (d) recovering the fully water-miscible solvent by distillation and washing; (e) recycling the fully water-miscible solvent to step (b) to provide a recycled solvent mixture; and (f) repeating steps (c), (d) and (e) with the recycled solvent mixture to provide a phosphoric acid having a preselected degree of purity.