Kaolin waste dumps contain a huge volume of material that cannot be commercialized due to the presence of variable amounts of iron minerals, which impart a yellowish color to the kaolin. Elimination of iron from kaolin using either a chemical or a biological method was the aim of this study. The chemical leaching of iron from kaolin was carried out using response surface methodology to optimize the reaction conditions. Time was found to be the most influential variable, although oxalic acid must be present to leach 32% of the iron. Biological leaching was also assayed for 14 days using a Bacillus strain. The results of bacterial leaching of iron from kaolin showed <1% iron elimination.

高岭土垃圾场含有大量无法商业化的材料，因为存在大量铁矿物，这些铁矿物使高岭土呈淡黄色。使用化学或生物方法从高岭土中去除铁是本研究的目的。采用响应面法对高岭土中的铁进行化学浸出以优化反应条件。时间被发现是最有影响的变量，尽管必须存在草酸才能浸出 32% 的铁。还使用芽孢杆菌菌株测定了 14 天的生物浸出。从高岭土中细菌浸出铁的结果表明铁的消除<1%。