This work aimed at maintaining Fe(III) in soluble form at circumneutral pH and separating it from the treated effluent by using the heterogeneous catalyst of Fe(III)–ethylenediaminetetraacetate complex ([FeEDTA]⁻) intercalated layered double hedroxides (LDHs) in the UV-Fenton process for the degradation of azocarmine B (ACB). All samples were fully characterized by various techniques and the results indicated the successful intercalation of [FeEDTA]⁻ within the interlayer of layered double hedroxides. In the decolorization and mineralization of the ACB process, the obtained catalyst showed a high photo-catalytic activity and an excellent stability at circumneutral pH. In addition, response surface methodology (RSM) was employed to optimize operating variables, and these mathematical models produced a satisfactory fit. The optimum conditions for ACB degradation were confirmed to be 6.54 initial pH, 100 mg L⁻¹ ACB concentration and 11.5 mM H₂O₂ concentration. Under the optimum conditions, the maximum ACB decolorization efficiency and TOC removal could reach up to 97.27% and 90.36%, respectively, which closely agreed with the predicted values. Finally, the possible reaction mechanisms involved in the heterogeneous UV-Fenton system were proposed.