Purification of Lanthanum Oxide by Magnetic Nano-Composite Alginate Beads after Its Concentration from Acidic Monazite Leach Liquor.

Lanthanum represents nearly fifth of Egyptian mineral monazite total rare earth content. Due to its great industrial importance in applications, the present research is directed to its concentration to the highest possible grade then, its purification from the other minor coherent neighbor rare earth elements (REEs). Rare earth hydrated oxide cake was produced from Egyptian crude monazite mineral (54% purity, -125 mesh size) after its digestion with concentrated sulfuric acid, its dissolution with water, thorium separation, purification from uranium and then group precipitation of total rare earth elements as ammonium sulphates. Total REEs precipitate was transformed to its hydrated oxide form after its caustafication process. REEs hydrated oxide cake is subjected to process of cerium oxidation and separation. REEs cake after ceria separation contains nearly half of its content from lanthanum and subjected to air-ammonia precipitation scheme at different pH values to get a higher lanthanum concentrate, which reach to 78.6% purity with 85.5% recovery at pH5.8. Magnetic alginate beads are used as biosorbent for sorption of lanthanum (III) from an aqueous medium of pH 5.8. The magnetic alginate sorbent is one of the highest adsorption capacities, which equal 1.8 mmol gP-1P or 0.25g/g. Column of 57 cm length, 1.2 cm diameter with flow rate 1ml/min experiment was carried out for adsorption of lanthanum which reaches to more than 99.68% purity with 80.7% recovery after elution with 1N HCl and 1N CaClR2R at pH 3.5-4.