Abstract Synthesis of amorphous aluminosilicates from high impurities in Indonesian kaolin were carried out in several ways, directly from kaolin and indirectly from metakaolin (calcined kaolin), both with silica addition and without silica addition. Synthesis was conducted in a gradual temperature hydrothermal reaction and in a constant temperature hydrothermal reaction. Before being synthesized, kaolin impurities were separated according to density and/or particle size by centrifugation. X-Ray Diffraction and FTIR Spectrometry characterization of the synthesized product showed that the results of synthesis of aluminosilicates from metakaolin via hydrothermal with gradual temperature or constant temperature produced aluminosilicates with high quartz impurities, while synthesis with the addition of silica in hydrothermal conditions at 80°C for 12 hours can produce aluminosilicate with a low quartz content. Direct synthesis from kaolin with the addition of silica could produce pure aluminosilicates. Graphical Abstract

中文翻译：

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从不纯的印尼高岭土合成无定形铝硅酸盐

摘要 从印度尼西亚高岭土中的高杂质合成无定形铝硅酸盐有多种方法，直接从高岭土和间接从偏高岭土（煅烧高岭土），添加二氧化硅和不添加二氧化硅。合成在缓温水热反应和恒温水热反应中进行。在合成之前，高岭土杂质根据密度和/或粒度通过离心分离。合成产物的 X 射线衍射和 FTIR 光谱表征表明，从偏高岭土通过渐温或恒温水热法合成铝硅酸盐的结果产生了具有高石英杂质的铝硅酸盐，而在 80°C 的水热条件下添加二氧化硅 12 小时的合成可以产生石英含量低的铝硅酸盐。从高岭土中加入二氧化硅直接合成可以生产纯铝硅酸盐。图形概要