煤气化细渣高炭组分中铁铝钙元素有机酸高效浸出与分离研究OA

The efficient extraction and separation of valuable metal elements from coal gasification fine slag(CGFS)are crucial for the comprehensive high-value utilization of its constituents.This study focused on the carbon-rich components of CGFS(CGFS-H)and systematically investigates the selective leaching behavior of Fe3+,Al3+and Ca2+using three organic acid extractants,i.e.,citric acid,tartaric acid,and tetrasodium iminodisuccinate.Additionally,the stepwise leaching of iron,aluminum and calcium from CGFS-H is explored.The selective dissolution mechanisms of these metals by different organic acids are elucidated through X-ray diffraction(XRD),X-ray fluorescence(XRF),and scanning electron microscopy(SEM)analyses.The results indicate that tetrasodium iminodisuccinate exhibits the highest leaching selectivity for Fe3+,while tartaric acid demonstrateds a comparable affinity for both Fe3+and Al3+.In contrast citric acid shows superior selectivity toward Ca2+.The leaching yield of Fe3+,Al3+and Ca2+after sequential leaching with the three organic acids were 79.8％,65.08％and 78.6％,respectively.These findings confirm that effective and selective separation of Fe3+,Al3+and Ca2+from CGFS-H can be achieved via optimized organic acid-based leaching strategies.This advancement provides a critical foundation for developing Ca/Fe/Al hydrotalcite materials using CGFS-H as a sustainable feedstock,thereby facilitating the transformation of waste residue into high-value functional materials and promoting resource-efficient utilization of coal gasification fine slag.