Comparison study on dye degradation by PDA-SF/AgNPs-H2O2 and PDA-SF/AgNPs-PMS catalytic system

In this work, polydopamine (PDA) was used to facilitate the reduction of silver nitrate (AgNO3) to silver nanoparticles (AgNPs) and the simultaneous loading on waste silk fabrics (PDA-SF/AgNPs). The removal activity of the obtained composite PDA-SF/AgNPs on different dyes in the presence of hydrogen peroxide (H2O2) and potassium peroxymonosulfate (PMS) was compared. The effects of reaction temperature, H2O2/PMS dosage, dye concentration, composite dosage, electrolyte concentration and time in two catalyst systems on the dye removal were discussed. The results showed the dye removal of Telon Red A2R reached 81% and 95% in 30-50 min in PDA-SF/AgNPs-H2O2 and PDA-SF/AgNPs-PMS system, respectively. Quenching experiments demonstrated that ·OH, ·O2- and SO4-· were produced during the degradation process, and the possible degradation pathway of Telon Red A2R were analyzed by HPLC-MS. In addition, the kinetic study indicated that the removal of dye followed quasi-second-order adsorption kinetics. These findings suggest that fabric-based composites have great potential and applications in catalysis and treatment of wastewater.