Photocatalytic degradation of textile dye utilizing biocl: synthesis, optimization, characterization and toxicity assessments

In this study, BiOCl was synthesized hydrothermally to optimize effective synthesis parameters, which had previously not been addressed systemically. In this regard, optimal synthesis parameters such as temperature (157 °C), pH (8.97), residence time (23.96 h) and concentration of mannitol (0.458 mol/L) were specified utilizing central composite design (CCD) methodology. In order to investigate characterizations of the photocatalyst, various techniques such as FTIR, XRD, DRS, FESEM, EDX, EIS and mapping were employed. Moreover, the influence of various operational parameters such as pH (5, 7, 9), catalyst dosage (0.1, 0.5, 1 g/L) and pollutant concentration (10, 20, 50 ppm) were assessed. The obtained results revealed that at optimal operational conditions (pH = 5, catalyst dosage = 0.5 g/L and pollutant concentration = 20 ppm), the dye is removed completely within 90 min. Furthermore, in order to investigate the degradation pathway due to the generated intermediates, the secondary wastewater was analyzed by GC-MS. Finally, toxicity evaluation of generated species was assessed by T.E.S.T. The obtained results demonstrated that the toxicity of generated intermediates is about AO7 or lower, which, proves that this photocatalyst demonstrates effective performance.