Adsorption of organic compounds on the Fe3O4 nanoparticles for forestalling fouling in membrane bioreactor

Many studies have been done to reduce the membrane fouling and to increase the quality of the effluent from membrane bioreactor (MBR). One of the most important researches in this filed is the use of adsorbents and nanoparticles in the biological system. In this study, the effects of Fe3O4 nanoparticles were investigated using COD, extracellular polymeric substances (EPS), soluble microbial products (SMP), flux, particle size distribution (PSD) and FTIR analysis. The COD test showed that the removal rate was 86.92% in MBR without Fe3O4 (R1) and 98.17% in MBR with Fe3O4 (R2). The amount of EPS and SMP in the reactor containing nanoparticles is lower than that of a nonnanoparticle reactor. Flux rate is higher in R2, so it can be said that the presence of nanoparticles has a positive effect of reducing the membrane fouling. Also, FTIR analysis showed that the amount of protein in the biologic system R2, which is the major membrane contaminant, is greater than R1.