| Membrane osmotic quantity and selective exist mutual restriction relations, this requires that we make through physical and chemical modification of membrane materials with good osmotic quantity and selectivity. This thesis polyether sulfone was synthesized through condensation and bromine chemical modified polyether sulfone, mixed with NH2-MIL-53, finally investigates the bromine generation, doping amount, temperature and pressure effects on the osmotic quantity of membrane. Specific research contents include:1. PESF was synthesized through condensation reaction with 4-Fluorophenylsulfone, 3,3′,5,5′-methyl-4,4′-diphenyl phenol and bisphenol AF, characterized by FTIR and H1-NMR. This paper tested the different pressure(0.5 atm, 1.0 atm, 1.5 atm) and different temperature(25 ℃, 35 ℃, 45 ℃and 55 ℃) under the condition of permeability coefficient, diffusion coefficient and the solubility coefficient. The results showed that with the increase of pressure, the CO2 permeability coefficient showed the trend of gradually reduce; With the increase of temperature, CO2 permeability coefficient showed the tendency of ris ing. Pressure and temperature effect on the permeability coefficient was mainly caused by the diffus ion coefficient. Under the condition of 25 ℃, 1 atm, the CO2 permeation of PESF was 10.2 bar, CO2/CH4 and CO2/N2 selectivity were 23.9, 25.6.The decomposition temperatureof PESF was 340 ℃ or so.2. BPESF was synthesized by bromination reaction. Products were characterized by FTIR and H1-NMR, proving successful synthesis and measured the bromine generation rate were 2.6 %, 12.2 %, 26 %, 32.5 % and 52.6 %. For five different bromine generation proportion of polyether sulfone, this paper examines the bromine generation degrees, the influence of temperature and pressure on the diffusion coefficient. Results show that with the increase of bromine generation degrees, CO2 permeability coefficient shows the trend of ris ing, this is the causes of polymer free volume increases; with the increase of temperature, CO2 permeability coefficient shows the trend of ris ing; with the increase of pressure, the CO2 permeability coefficient shows the tendency of gradually reduce. Pressure and temperature effect on the permeability coefficient was mainly determined by the diffusion coefficient. Combined with CO2 permeability coefficient and CO2/CH4, CO2/N2 selectivity, BPESF–d(1:4) showed the best separation performance. The permeation of CO2 is 50.2 bar, CO2/CH4 and CO2/N2 selectivity were 23.4 and 22.4. TG and DSC analys is results showed that with the increase of bromine generation degrees, the temperature of the polymer started to break down gradually rising.3. Mixed matrix membrane(5 %, 10 %, 15 %) were prepared with NH2-MIL-53 as inorganic particles dispersed phase. First of all, NH2-MIL-53 were analyzed by XRD and FTIR, proved the successful synthes is. And FTIR analys is was carried out on the mixed substrate membrane, the results showed that with the increase of doping amount, NH2-MIL-53 characteristic peak gradually enhanced. Gas performance tests showed that with the increase of doping amount, the permeation of CO2 increased gradually, CO2/CH4 and CO2/N2 selectivity decrease after ris ing first, because with the increase of doping amount, the inorganic particles NH2-MIL-53 reunion phenomenon happened. Finally the SEM, TG and DSC for mixed matrix membrane were analyzed, the results showed that 10% mixed matrix membrane has good dispersibility, 15 % of the mixing matrix membrane appeared an obvious phenomenon of reunion. TG showed that with the increas ing of the doping amount, the temperature of the polymer started to break down gradually ris ing. When NH2-MIL-53 added amount to 10 wt %, mixed matrix membrane showed the best gas permeability. The CO2 permeability coefficient is 113.0 bar, increased by 125 % compared with before doping. CO2/CH4 and CO2/N2 selectivity reached 28.5 and 29.2 respectively, reached 1991 Robosen upper bound increaseing by 19.2 % and 14.1 %. |
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