Inorganic Ceramic Membrane Modified With The Support Body Binding Study

The preparatio n techno logy re form o f Al₂O₃film, the e ffects of d iffere ntadditions on the Al₂O₃film and SiO₂film, and the b ind ing of film a nd aluminasupport were investigated by sol-ge l method and differe nt additio ns in thedissertation.The film was eharacterized by thermogra vimetric ana lys is, infraredspectrum ana lys is, specific surface area analys is, atomic force microscopy,porosity measure me nt and ana lys is， etc.in order to get a comp lete, goodperforma nce of the Al₂O₃and SiO₂films. The dissertation was ma inly d iscussed asfollows:（1） The preparatio n process o f Al₂O₃film was re formed by So l-ge l method.The effects of So lve nt ethano l content on a lumina membra ne were investigatedand obtained the optimized cond itio ns.When tota l so lvent co ntent was66.4mLand the vo lume ratio of water and etha no l was7:1,we c ould got good stability、flatness and higher porosity film. The viscosity o f so lution was6.45mPa·s,andthe average pore size was about20.2659nm. At the same time, the effects of theraw materia l pretreatme nt on Al₂O₃me mbra nes were examined. The researchfound that it was conduc ive to the formatio n of macromo lecular so lution toensure that the hydrolys is of alkoxide kept on the ho moge neous mo lecular leve l,and the aging reflux time o f sol greatly reduced to6h a fter immers ing Aluminumisopropoxide.（2）The Al₂O₃film was effected by PVA, PEG-300, PEG1-000, PEG-2000,DMF,MC. The film e ffect, drying tim,s uitab le viscos ity a nd other factors wereconsidered,so the film forming effect was PVA> PEG-300> PEG-1000>PEG-2000> DMF> MC. we used sol-ge l method and could got s mooth, uniformsurface with high porosity films a fter adding10%PVA. The pore sizedistrib ution of Al₂O₃films was uniform. The hardness of Al₂O₃films was2H andaverage pore size was about50.3714nm. （3）The properties of thin films were greatly influe nced by sintering syste m.The sintering syste m was fro m0to100℃, the heating rate was0.25℃/min,and thermal insula tion is120min at100℃. The s intering syste m was fro m100to400℃, the heating rate was0.5℃/min, and therma l ins ulatio n is120min at400℃. The sintering syste m was form400to800℃, the heating rate was1℃/min, and therma l ins ulatio n was120min at800℃.when the last te mperaturereduced to20℃,the good performance of the membrane was obtained.（4） The S iO2film was effected by DMF,MC, PVA, PEG-300, PEG-1000,PEG-2000. Adding30%DMF could effective ly prevented the ge l cracking, keptgood and inte grity the ge l fra me a nd enlarged the aperture function. The a veragepore rad ius o f SiO₂film was7.08nm, pore vo lume was0.188320cm3/g, andsurface area was53.168m2/g after adding DMF; Each100ml so l was jo ined by0.35g methyl cellulose,whic h could pla yed a thickening role. The interna lstructure of SiO₂film was uniform, pore size distrib utio n was narrow and surfacewas smooth. The most recent ava ilab le aperture was1.14nm and less than2nmwas96.7%; After add ing15%PVA, we coule produced good smoothness, higherporosity S iO2film.The pore size d istributio n was uniform, pore shape wasfrustum of a cone, the specific surface area was281.872m2/g, and the averagepore radius was2.4nm; The so l viscosity s uitab le, drying cond itio ns, ge ltime,etc.were cons idered,so the film forming effect was PEG-300> PEG-1000>PEG-2000.PEG-300could reduced viscosity, decreased pore size, improvedsurface area and therma l stability,comformed to law of its crit ica l mice lleconcentration a nd the CMC was about6.16x10-3L/L. After15%（massfraction） PEG-300, the specific surface area was334.889m2/g, the pore volumewas0.280435cm3/g, the average pore radius was2.36nm and the most probablepore radius was1.04nm.（5） The Compositio n of SiO₂, Al₂O₃films and Al₂O₃supporting body b ind ingwas investigated. With the increase of coating times,we decreased viscosity o f thesol,and we could got s mooth, integrity films by se lecting the sol viscosity o f5-7mPa s, pulling speed of1.5-2mm/s. The pure water flux of Al₂O₃film was1.55²times tha n Al₂O₃nano meter me mbrane. The pure water flux o f SiO₂film was1.55to3.1than inorganic me mbrane. Under the0.1Mpa pressure, the pure water flux of S iO2me mbrane was1438.711L/m2h, the porosity was30.97%afteradding PVA. Under the0.1Mpa pressure, the pure water flux of Al₂O₃me mbranewas930.009L/m2h,the porosity was30.397%after adding PVA. Under the0.1Mpa pressure, the pure water flux o f SiO₂me mbrane was909.27L/m2h,theporosity was28.9%after add ing PEG-300. Under the0.1Mpa pressure, the purewater flux of Al₂O₃me mbrane was1172.283L/m2h,the poros ity was33.76%afteradding PEG-300。...