The photocatalytic reaction with Bi₂WO₆ as a catalyst is found to be effective for removal of tetracycline in wastewater. In this paper, the treatment efficiency of Bi₂WO₆ photocatalyst for tetracycline wastewater is further improved through directly adding photosensitizer to the photocatalytic reaction. Bi₂WO₆ catalyst is prepared and characterized by XRD and SEM to explore its crystal structure and morphology. Meanwhile, the effects of five factors including anion, cation, photosensitizer dosage, initial concentration of tetracycline, and initial pH of tetracycline on the removal of tetracycline are studied. The results show that the photocatalyst is successfully prepared without any damage to the lattice structure, and that addition of sensitizer can improve adsorption and removal of tetracycline, and that the catalytic activity of Bi₂WO₆ is optimized. The promotion effects of anion Cl^- and cationic Cu²⁺ are better than others, and after comparison the best photosensitizer is found to be copper sulfate. The removal rate of tetracycline can reach 88.79% when the addition of copper sulfate is 1.5 ml and the initial concentration of tetracycline is 70 mg/L. Besides, the adsorption efficiency is the best when pH is 5 or 8, the adsorption rates being 51.50% and 55.01%, respectively.

tetracycline  /  bismuth tungstate  /  inorganic salt ions  /  photosensitizer