Preparation And Properties Of Go-agnps/polymer Hybrid Membranes For Pervaporation Of Benzene/cyclohexane Mixtures

Nowadays,design and construct high-performance separation membranes for specific separation systems is one of the developmenttrends of membrane technology.In this thesis,in order to obtain high separation membrane for benzene/cyclohexane mixtures pervaporation,graphene oxide-Ag nanoparticle composites were synthesized by impregnation-reduction method using polyethylene glycol(PEG-400)as the reducer and AgNO3 or silver ammonia as the precursor,which were then blended with polyimide(PI)or polyurethane(PU)to prepare GO-AgNP/PI(PU)mixed matrix membranes.The thesis firstly studied the imfact of different Ag nanoparticle precursor,reducing agent and amount of Ag nanoparticles doped to graphene oxide-Ag nanoparticles(GO-AgNPs)compound and GO-AgNPs/PI hybrid membrane structure and performance.GO-AgNPs complex structure were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectrum analyzer(FT IR),Raman spectroscopy and so on;GO-AgNPs/PI hybrid membranes which were characterized by transmission electron microscope(TEM),scanning electron microscope(SEM)analysised the hybrid membrane thermo-gravimetric,surface electrical charge and pervaporation performance of benzene/cyclohexane mixtures.The results showed that GO-AgNPs prepared with PEG-400 as the reducing agent,Ag as the precursor and GO as the carrier and the content of Ag nanoparticles was 15%had the best stability.With the increase of Ag doping amount,the fluxes and separation factors of GO-AgNPs/PI mixed matrix membranes first increased and then decreased.When the content of Ag nanoparticles was 15%,the separation factor of hybrid membrane is the highest.Secondly,the thesis studied the pervaporation performance of the hybrid membrane which maybe different by changing the based membrane material,the temperature of material liquid and the concentration of liquid.It was found that the separation factor of GO-AgNPs/PU mixed matrix membrane was higher than that of GO-AgNPs/PI mixed matrix membrane,but the difference of separation factor was high in GO-AgNPs/PI mixed matrix membrane;in different concentrations of benzenethe,the tend of flux and separation factor of GO-AgNPs/PI mixed membrane were the same,and both increased with the increase of benzene concentration;in the different temperatures,the tend of flux and separation factor of GO-AgNPs/PI mixed matrix membrane were the same.The flux of membrane increased with increasing temperature,while membrane separation factor decreased.