| This Master’s thesis was built on the study of the design, preparation, characterization and wastewater-treatment performance of several polymer matrix composites.Adsorption of Cr(VI) from aqueous solution onto a magnetic chelating resin with EDTA functionality (magnetic PS-EDTA) was investigated in a batch system. Various factors affecting the uptake behavior such as pH, contact time, initial concentration of the metal ions and dosage of resins on Cr(VI) removal were studied. The magnetic modified resin showed higher adsorption capacity and shorter adsorption equilibrium time for Cr(VI) compared with the raw resin. The equilibrium data were analyzed using the Langmuir, Freundlich and Tempkin isotherm models among which Langmuir isotherm model was found to be suitable for the monolayer adsorption process. The monolayer adsorption capacity values of123.05mg/g for raw PS-EDTA and250.00mg/g for magnetic resin were very close to the maximum capacity values obtained at pH4.0. Kinetic studies showed that the adsorption followed a pseudo second-order reaction. The mechanism was further identified by fitting intraparticle diffusion and McKay plots. The result indicates film diffusion was the rate-limiting step and intraparticle diffusion was also involved in adsorption. XPS spectra confirmed that reduction of Cr(VI) by FesO4nanoparticle on the resin occurred, while the electrostatic interaction between protonated amine groups and Cr(VI) anion played an important role in the adsorption. Furthermore, the resin could be regenerated through the desorption of the Cr(Ⅵ) anions using0.5M NaOH solution and could be reused to adsorb again.Concerning about environmental pollution and health safety risks, waterborne polyurethane (WPU), in place of conventional binders, was introduced into preparing an active carbon/polyurethane foam, active carbon/WPU foam (AC/WPU foam), via two sequential steps. The scanning electron microscopy and wettability tests showed that the WPU-based process was effective for achieving a higher active carbon content, enhanced pores wall roughness and improved hydrophilicity of the foam which was explained by infrared spectroscopy. Adsorption behavior of the AC/WPU foam for phenol in aqueous solutions was investigated by batch experiments. The results showed that the maximum removal capacity of phenol (5000mg/dm3) with0.389dm3/L of sorbent was observed at100mg/L at pH7. Removals of over85%occurred in2.5h, and the loading half-time was calculated to be only26.77min. In addition, adsorption kinetic data were described by pseudo-second-order equation and the equilibrium data fitted very well with the Langmuir and Temkin model. Further the AC/WPU foam could be fully recycled via0.01M NaOH. In general, WPU as an environmentally friendly binder had excellent application in preparing AC/WPU foam. Meanwhile, this foam should be a promising adsorbent in the recovery of phenol.We have prepared a magnetic PUF via solution-depositing method and studied the useful purpose of magnetism in the microorganism degradation. The characteristics of DMP degradation by immobilized cells in PUF with different magnetic nanoparticle content were investigated. The results showed the magnetic PUF with high nanoparticle content (40wt.%) was more favorable than that with lower nanoparticle content (10wt.%), and both of them were better than rude PUF for microorganism immobilization. The semi-continuous degradation test demonstrated that the degradation rate of immobilized cells in magnetic PUF was increased as the rise of magnetic nanoparticle content. The structure of the magnetic PUF was characterized by means of infrared spectroscopy and scanning electron microscopy. The thermal stability was tested by thermogravimetric analysis. |
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