In this study, aluminum, iron, calcium and magnesium existing in thermal power plant fly ash were leached by the method of hydrochloric acid with 20% acetic acid. Then, solvent extraction and precipitation methods were applied for recovery processes. The effects of acid concentration, reaction time, and temperature on leaching of iron, aluminum, calcium, and magnesium were investigated considering the Taguchi experimental design. The optimal leaching efficiencies of these elements were obtained under the experimental condition of 5 molar acid concentration, a 240 min reaction time, and 90 °C reaction temperature and removal efficiencies were obtained for iron, aluminum, calcium and magnesium as 95%, 87%, 87%, and 96%, respectively. Almost all the tested elements were successfully recovered from leaching solution of elements by solvent extraction and precipitation processes, which are considered as recovery processes. This study indicated that the proposed methods could be applied in recovery of metals from fly ash samples successfully.

中文翻译：

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使用Taguchi实验设计优化火电厂粉煤灰中主要元素的回收率

在这项研究中，火电厂粉煤灰中存在的铝，铁，钙和镁通过盐酸与20％乙酸的方法浸出。然后，将溶剂萃取和沉淀方法应用于回收过程。考虑田口实验设计，研究了酸浓度，反应时间和温度对铁，铝，钙和镁浸出的影响。在酸浓度为5摩尔，反应时间为240分钟，反应温度为90°C的实验条件下获得了这些元素的最佳浸出效率，铁，铝，钙和镁的去除效率分别为95％，87％ ，87％和96％。几乎所有被测元素都通过溶剂萃取和沉淀过程从元素的浸出溶液中成功回收，这被认为是回收过程。这项研究表明，所提出的方法可以成功地用于从粉煤灰样品中回收金属。