Naphthenic acid separation of waste phosphors in acid leaching solution of iron and aluminum

In this paper, the effect of removing impurities of iron and aluminum in the process of naphthenic acid extraction of waste rare earth phosphors was studied. The selectivity of naphthenic acid for iron, aluminum and rare earth was investigated. The effect of organic phase composition, ammonia concentration and temperature on the separation effect; Influence of washing temperature and washing ratio on washing effect; Effect of hydrochloric acid concentration, comparison and back extraction time on back extraction effect. The results showed that the best separation effect was achieved when the volume ratio of naphthenic acid: isooctanol: sulfonated kerosene was 20:20:60, the concentration of ammonia was 2 mol/L, the temperature was 20 ℃, and the droplet acceleration of ammonia was 3 mL/min. When the washing temperature was 40 ℃ and the comparison (A/O) was 2, the elution rates of Fe, Al and Re were 1.5%、4.2% and 26.4%, respectively. When hydrochloric acid concentration was 3 mol/L, reverse extraction ratio (A/O) was 1 and reverse extraction time was 20 min, the extraction rates of iron, aluminum and rare earth were up to 99.5%、99.8% and 99.8% respectively.