The contribution by Mokoena et al. (2022, volume 259, article 104037) is flawed in the fundamental characterization of the fly ash. The TESCAN Integrated Mineral Analyzer (TIMA) is a tool designed for use with several-micron-scale crystalline particles, not for a fly ash largely composed of glass with nm-scale to micron-scale minerals. The Energy Dispersive X-ray Spectroscopy analysis is flawed by the selection of rare earth peaks that are either concealed by the stronger Ti and Fe peaks or cannot be distinguished from the background in the energy regions outside of the Ti and Fe peaks. Consequently, many of the minerals “identified” in the TIMA analysis were mistakenly considered to have observable concentrations of rare earth elements.

Mokoena 等人的贡献。（2022 年，第 259 卷，第 104037 条）在飞灰的基本表征方面存在缺陷。TESCAN 综合矿物分析仪 (TIMA) 是一种设计用于处理几微米级结晶颗粒的工具，而不是用于主要由具有纳米级至微米级矿物的玻璃组成的飞灰。能量色散 X 射线光谱分析存在缺陷，因为选择的稀土峰要么被更强的 Ti 和 Fe 峰所掩盖，要么无法与 Ti 和 Fe 峰之外的能量区域的背景区分开来。因此，许多在 TIMA 分析中“确定”的矿物被错误地认为具有可观察到的稀土元素浓度。