Synthesis and characterization of novel magnetic Fe3O4/polyurethane foam composite applied to the carrier of immobilized microorganisms for wastewater treatment

Abstract

The objective of this work was to prepare novel magnetic Fe3O4/polyurethane foam (Fe3O4/PUF) composites applied to the carriers of immobilized microorganisms for toluene-containing wastewater treatment. The morphology and structure of Fe3O4/PUF composite were characterized by X-ray diffraction, Fourier transform IR spectroscopy, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and magnetic property measurement system. These morphological investigations revealed that Fe3O4 nano-particles were well dispersed into the matrix of PUF with nano-scale diameter particles. TG experiments indicated that the initial thermal weight loss temperatures of composite with the content of 2.5 wt% and 7.5% Fe3O4 were increased by 7 and 16 °C, compared with pure PUF. The degradation efficiency of toluene with magnetic PUF composite was much higher than that of pure PUF carrier, and the reason why the immobilization of microbial biomass of microorganisms on the magnetic PUF composite was much higher than that of the pure PUF. The prepared magnetic Fe3O4/PUF composite offered excellent thermal stability and medium paramagnetic properties. And this composite could not only increase the immobilized biomass of the microorganisms, but also enhance the COD removal efficiency of wastewater.