AbstractThe degradability of an azo dye (C.I. Acid Black 2), synthetic and real dyebaths, and actual textile dyeing wastewater were investigated using a homogeneous and heterogeneous Advanced Oxidation Processes (AOPs) in combination with power ultrasound (US). The components of the homogeneous process were US, short wave UV-C and ferrous ions, and those of the heterogeneous were US, short wave UV-C, ZnO and H