A novel thermally induced graft polymerization technique was used to modify a polyvinylidene fluoride （PVDF） hollow fibre microfiltration membrane. An artificial neural network （ANN） was applied to optimize the pr...A novel thermally induced graft polymerization technique was used to modify a polyvinylidene fluoride （PVDF） hollow fibre microfiltration membrane. An artificial neural network （ANN） was applied to optimize the prepared condition of the membrane. The optimized dosing of acrylic acid （AA）, acrylamide （AM）, N, N＇- methylenebisacrylamide （NMBA） and potassium persulphate （KSP） designed by ANN was that AA was 40.63 ml/L; AM acted as 6.25 g/L; NMBA was 1.72 g/L and KSP was 1.5 g/L, respectively. The thermal stability of the PVDF modified hollow fibre membrane （PVDF-PAA） was investigated by thermogravimetric （TG） and differential scanning calorimetry （DSC） analysis. The polycrystallinity of the PVDF-PAA membrane was evaluated by X-ray diffraction （XRD） analysis. The complex formation of the modified membrane was ascertained by Fourier transform infrared spectroscopy （FTIR）. The morphology of the PVDF-PAA membrane was studied by environmental scanning electron microscopy （ESEM）. The surface compositions of the membrane were analyzed by X-ray photoelectron spectroscopy （XPS）. The adsorption capacity of Cu^2＋ ion on the PVDF-PAA hollow fibre membrane was also investigated.展开更多
针对超滤膜在处理含油污水过程中膜污染严重的问题,采用自由基聚合法结合机械搅拌制备P(MAAc-co-MAAm)多氢键自组装凝胶微球,并通过分子间多氢键的作用沉积于羧基化的聚偏氟乙烯(PVDF)膜表面,制备凝胶微球改性PVDF超滤膜;通过动态光散...针对超滤膜在处理含油污水过程中膜污染严重的问题,采用自由基聚合法结合机械搅拌制备P(MAAc-co-MAAm)多氢键自组装凝胶微球,并通过分子间多氢键的作用沉积于羧基化的聚偏氟乙烯(PVDF)膜表面,制备凝胶微球改性PVDF超滤膜;通过动态光散射粒度分析仪测试微球粒径,采用场发射扫描电子显微镜及原子力显微镜观察膜表面形貌,并通过接触角、水下油滴粘附和油水乳液过滤等测试方法表征膜的性能。结果表明:微球平均粒径约248 nm,改性膜的水接触角最低可达25.4°±1.5°,且具有优异的水下抗油滴粘附性能。由40 mL P(MAAc-co-MAAm)凝胶微球悬浮液改性的PVDF膜对平均粒径为220 nm的正己烷水包油乳液的截留率高达99.8%,4次油水乳液循环测试后,通量恢复率高达85.2%,而原膜的通量恢复率仅为41.5%,说明凝胶微球改性膜具有优异的抗污染能力,同时保证了改性膜优异的分离性能。展开更多
文摘A novel thermally induced graft polymerization technique was used to modify a polyvinylidene fluoride （PVDF） hollow fibre microfiltration membrane. An artificial neural network （ANN） was applied to optimize the prepared condition of the membrane. The optimized dosing of acrylic acid （AA）, acrylamide （AM）, N, N＇- methylenebisacrylamide （NMBA） and potassium persulphate （KSP） designed by ANN was that AA was 40.63 ml/L; AM acted as 6.25 g/L; NMBA was 1.72 g/L and KSP was 1.5 g/L, respectively. The thermal stability of the PVDF modified hollow fibre membrane （PVDF-PAA） was investigated by thermogravimetric （TG） and differential scanning calorimetry （DSC） analysis. The polycrystallinity of the PVDF-PAA membrane was evaluated by X-ray diffraction （XRD） analysis. The complex formation of the modified membrane was ascertained by Fourier transform infrared spectroscopy （FTIR）. The morphology of the PVDF-PAA membrane was studied by environmental scanning electron microscopy （ESEM）. The surface compositions of the membrane were analyzed by X-ray photoelectron spectroscopy （XPS）. The adsorption capacity of Cu^2＋ ion on the PVDF-PAA hollow fibre membrane was also investigated.
文摘针对超滤膜在处理含油污水过程中膜污染严重的问题,采用自由基聚合法结合机械搅拌制备P(MAAc-co-MAAm)多氢键自组装凝胶微球,并通过分子间多氢键的作用沉积于羧基化的聚偏氟乙烯(PVDF)膜表面,制备凝胶微球改性PVDF超滤膜;通过动态光散射粒度分析仪测试微球粒径,采用场发射扫描电子显微镜及原子力显微镜观察膜表面形貌,并通过接触角、水下油滴粘附和油水乳液过滤等测试方法表征膜的性能。结果表明:微球平均粒径约248 nm,改性膜的水接触角最低可达25.4°±1.5°,且具有优异的水下抗油滴粘附性能。由40 mL P(MAAc-co-MAAm)凝胶微球悬浮液改性的PVDF膜对平均粒径为220 nm的正己烷水包油乳液的截留率高达99.8%,4次油水乳液循环测试后,通量恢复率高达85.2%,而原膜的通量恢复率仅为41.5%,说明凝胶微球改性膜具有优异的抗污染能力,同时保证了改性膜优异的分离性能。
