Preparation Of Inorganic-organic Hybrid Membranes Based On Ionic Liquid Microemulsion And Pervaporation Of Benzene/Cyclohexane Mixture

Recently, polymer-silver salt hybrid membranes have been intensively studied for separation of Olefin/paraffin mixture by pervaporation. And preparation of hybrid membranes via reverse microemulsion and in situ polymerization has become a new and interesting research topic. In this thesis, AgCl nanoparticles were firstly synthesized in reverse microemulsion using ionic liquid1-dodecyl-3-methyl imidazoium chloride (C12mimCl) as surfactant, alcohol as cosurfactant, acrylic ester and acryl amide (AM) as oil-continuous phase. Then, AgCl/poly(MMA-co-AM) copolymer hybrid membranes were prepared by microemulsion polymerization. And the pervaporation experiments for benzene/cyclohexane mixtures were employed to evaluate the performance of hybrid membranes. The main research contents as follow:Firstly, the phase behavior and the stability of (C12mimCl+alcohol)/(acrylic ester+AM)/(KNO3+H2O) microemulsion was analyzed through the measurement of conductivity. The results demonstrated that C12mimCl had good emulsifiability. The stability of microemulsion decreased at high temperature. And the increase of aliphatic chain length of alcohol and acrylic ester depressed the solubilization ability of microemulsion. CkNO3had significant influence on the formation of the ionic liquid microemulsion. The reverse microemulsions were easier to form at high concentration of KNO3.Then, AgCl nanoparticles were synthesized by precipitating AgCl in (C12mimCl+C6H14O)/(MMA+AM)/H2O microemulsion. The effects of ω (ω, water to surfactant mole ratio), CAgNO3, CC12mimcl, Cc6H14O on the particle size and distribution of AgCl nanoparticles were investigated. The results showed that AgCl nanoparticles in the microemulsion were spherical or sphere-like, the average diameter was less than25nm and the distribution was relatively narrow.(1) The size of AgCl nanoparticles increased first then reduced with the raise of ω.(2) Higher concentration of AgNO3favored formation of larger AgCl nanoparticles.(3) More AgCl nanoparticles with smaller size and uniformity distribution were synthesized when CC12mimcl increased in a certain range.At last, AgCl/poly(MMA-co-AM) hybrid membranes were prepared via microemulsion polymerization. The structures of hybrid membranes were characterized by FT-IR, SEM, XRD and TGA. FT-IR results indicated that the interactions of Ag+with the carbonyl of acrylamide could form-(H2N)C=O¨Ag+complexation. The results of SEM and XRD proved that AgCl nanoparticles with small size were well-distributed in the hybrid membranes.The swelling-sorption behaviors and pervaporation performance of AgCl/poly(MMA-co-AM) hybrid membranes for benzene/cyclohexane mixtures were studied. The results demonstrated that swelling-sorption amount of benzene in the hybrid membranes was much larger than that of cyclohexane. The addition of AgCl nanoparticles obviously improved the separation performance of hybrid membranes. The maximum separation factor of5.0with the flux of406g·m-2·h-1was obtained.In conclusion, the AgCl/poly(MMA-co-AM) copolymer hybrid membranes containing AgCl nanoparticles exhibited well separation performances for benzene/cyclohexane mixtures. And the properties of nanoparticles could be regulated by adjusting the parameters of microemulsion.