Abstract Bauxite residue, as an important source of scandium, is an alkaline industrial waste generated during the Bayer process for alumina production. A novel method for selective extraction of scandium from bauxite residue was proposed by ammonium sulfate roasting and water leaching. During the roasting process, ammonium sulfate could selectively react with Sc, Al and Fe in the bauxite residue to produce respective metal ammonium sulfates, and then which were completely decomposed to their respective metal sulfates at 550 °C. The sulfates of iron (III) and aluminum were decomposed to their respective metal oxides at about 700 °C, whereas the scandium sulfate remained stable. In the leaching process, the scandium sulfate could be selectively leached with water from roasted residues while other elements mainly remained in the leaching residue. The extraction efficiency of scandium reached above 90% under the optimum conditions.

中文翻译：

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硫酸铵焙烧浸出工艺从铝土矿渣中选择性提取钪

摘要 铝土矿渣是拜耳法氧化铝生产过程中产生的一种碱性工业废物，是钪的重要来源。提出了一种硫酸铵焙烧水浸法从铝土矿渣中选择性提取钪的新方法。在焙烧过程中，硫酸铵可以选择性地与铝土矿渣中的Sc、Al和Fe反应生成各自的金属硫酸铵，然后在550℃下完全分解成各自的金属硫酸盐。铁 (III) 和铝的硫酸盐在 700 °C 左右分解为各自的金属氧化物，而硫酸钪保持稳定。在浸出过程中，硫酸钪可以从焙烧渣中选择性地用水浸出，而其他元素主要留在浸出渣中。