A process for synthesizing Gamma alumina from kaolinitic sandstone ore has been described in this paper. Fine kaolin was recovered from the sandstones after aggressive attrition scrubbing process followed by 2" and 1" hydro- cyclone classification. The produced −25 μm kaolin was transformed to active meta-kaolin via calcination at 750 °C for 5 h. Through metakaolin- H₂SO₄ interactions, and consequently precipitation in ethanol solution, aluminum sulfate was formed. After dryness and calcination at 900 °C for 2 h γ-alumina was prepared. The FT-IR, DLS, BET, XRD, SEM and EDX analyses confirmed the high purity of the nanosized γ-alumina product. In addition, the prepared γ-alumina was examined as the sorbent for rare earth species from waste materials. Adsorption and thermodynamic studies, in addition to the adsorption selectivity, desorption process, and reusability showed promising performance results. The maximum adsorption capacity of the prepared γ-alumina reached 142 mg/g.

本文介绍了一种从高岭砂岩矿石中合成伽马氧化铝的工艺。经过剧烈的磨损洗涤过程，然后进行 2" 和 1" 水力旋流分级，从砂岩中回收了细高岭土。产生的-25 μm 高岭土通过在 750 °C 下煅烧 5 h 转化为活性偏高岭土。通过偏高岭土-H ₂ SO ₄相互作用，并因此在乙醇溶液中沉淀，形成硫酸铝。在干燥并在 900°C 下煅烧 2 小时后制备γ-氧化铝。FT-IR、DLS、BET、XRD、SEM和EDX分析证实了纳米级γ-氧化铝产品的高纯度。此外，制备的γ-氧化铝被检查为来自废料的稀土物种的吸附剂。除了吸附选择性、解吸过程和可重复使用性外，吸附和热力学研究显示出有希望的性能结果。制备的γ-氧化铝的最大吸附量达到142 mg/g。