The Removal of Fluorine from Wet Process Phosphoric Acid

The Removal of Radium During the Production of Nitrophosphate Fertilizer

“…Radium concentration in nitrophosphate solution is about one thousand times less than in the pitchblende and carnotite leach solutions ( and a uranium separation steps to produce nonradioactive fertilizer as shown in Figure 2. The defluorination step is another option that results into a high grade fertilizer and a sodium fluorosilicate by-product [13]. For the removal of radium, barium nitrate and potassium sulfate should be added and the precipitate formed is filtered off and disposed under controlled conditions, without interference with the fertilizer production.…”

Recovery of Uranium from Wet Phosphoric Acid by Solvent Extraction Processes

“…Options for treating the WPA include removal of the impurities from the WPA or extraction of phosphoric acid itself from the WPA. By employing the former approach, cadmium, − arsenic, ,, and fluorine ,,, can be removed from WPA by volatilization, chemical precipitation, or extraction to produce animal-grade phosphoric acid. Liquid–liquid extraction is a mature technology commonly used to purify WPA to produce food- or pharmaceutical-grade phosphoric acid.…”

Solubility of Mixed Ternary Systems of Hexafluoridosilicate Salts (M = Na+, K+, or NH4+) in Hexafluoridosilicic Acid Aqueous Solutions at T = 353.15 K

“…In addition, all of the equipment and appliances of these processes (pipes, pumps, heat exchangers, storage tanks, etc.) are oversized. − This leads to the shutdown of the production line. Deposits of hexafluoridosilicates are contributing to higher investment and operating costs, as well as higher material manufacturing costs and energy and operating costs.…”