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[Display omitted] • A resource utilization approach of field AMD for the formation of LDHs was proposed. • LDHs derived from field AMD possesses a larger removal capacity for Sb compared with other LDHs from chemical reagents. • Sb(V) removal by LDHs was attributed to anion exchange and formation of brandholzite. • The removal mechanism of Sb by LDHs was revealed by DFT calculations. Although acid mine drainage (AMD) has been recognized as a major environmental pollutant, it is also a potential source of valuable metals and sulfate. In this study, a resource utilization approach of field AMD for the formation of iron-based layered double hydroxides (LDHs) with sulfate intercalation was proposed and its capacity for removing antimonate [Sb(V)] was examined. Layered double hydroxides derived from field AMD possesses a more rapid equilibration time (<120 min) and a larger removal capacity (78 mg g−1) for Sb(V) compared with other LDHs from chemical reagents. Following the treatment of field AMD containing 10.7 mg L−1 Sb, a residual Sb concentration of 4.0 μg L−1 was achieved using a dose of 1 g L−1 LDHs, which meets the drinking water standard of 5 μg L−1 recommended by China's Ministry of Health. Leaching tests showed negligible metal(loid)s dissolution in Sb-loaded LDHs over a short period. The interactions between Sb(V) and LDHs include anion exchange and formation of brandholzite, which were further investigated at the electronic scale using density functional theory (DFT) calculations. It is envisaged that this approach for preparing LDHs will provide theoretical support for the remediation and resource recovery of AMD. [ABSTRACT FROM AUTHOR]