12597

1043 دكتري

دكتري

مهندسي شيمي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مهندسي شيمي

1396

[دوازده]، 92ص.: مصور، جدول، نمودار

ص. ع. به فارسي و انگليسي

علي كبر دادخواه، عبداللطيف هاشمي فرد

مرتضي صادقي، اميرحسين نوارچيان، محمد ديناري

1396/05/04

كتابنامه

مهندسي شيمي

مهندسي شيمي

ID1043 دكتري

93 Development of plasticization model for polymeric membranes and experimentalstudy of this phenomenon on the performance of PEI TiO2 mixed matrix membrane and effect of heat treatment on PEI membrane Masoud Saberi Masoud saberi@ce iut ac ir Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree PhD language Farsi Supervisors Dr Ali A Dadkhah Dr S A HashemifardAbstractOne of the problems which lie in separating CO2 from CH4 or N2 by glassy polymeric membranesis the plasticization that occurred at higher partial pressures than specific pressure Thisphenomenon causes the reduction in gas separation ability of glassy membranes It is known thatthe permeability of mixed gases is different from pure gases due to competitive sorption In thefirst part of this investigation a model for predicting the permeability and the effective diffusioncoefficient of mixed gases in the presence of plasticization were proposed In this model it wasassumed that the diffusion coefficient for all components was exclusively function of plasticizingcomponent Also the partial immobilization model was employed to determine the fraction ofmobile sorbed gases Then three groups of the experimental data from the literature including thepermeation of CO2 N2 and CO2 CH4 through asymmetric PI PES and CA membranes and also thepermeation of CO2 CH4 through dense CA membrane compared to the model and the coefficientsof the model were determined Plasticization parameter decreased for both components byincreasing the fraction of second component in the feed It means that plasticization of glassypolymers was suppressed This decrease was caused by competitive sorption between CO2 and thesecond component Also Immobilization factor of all components decreased with the increase inthe fraction of second component The effective diffusion coefficient for pure CO 2 wassignificantly pressure dependent due to the higher degree of the plasticization However withincreasing the fraction of second component in the feed this dependency decreased In the secondpart the effect of thermal treatment and also adding TiO2 nanoparticles on the performance ofasymmetric PEI membrane in separating CO2 from N2 were investigated Thermal treatment attemperatures lower and higher than Tg were done The results show that for the untreatedmembrane plasticization occurred with the increase in upstream pressure For the membraneswhich treated at 120 160 and 200 C for 5 hr plasticization pressured increased to 6 bars For themembrane which treated at 220 C for 10 min plasticization was not observed to 10 bars Moreover permeances of the gases through the treated membranes were lower than untreatedmembrane due to densification and the reduction in free volumes in the selective layer ForPEI TiO2 membranes with adding 1 and 2 wt of TiO2 plasticization pressure increased to 4 and5 bars due to the reduction in the movement of polymer chains and the increase in the resistance ofthe membrane For PEI 5 TiO2 plasticization occurred due to agglomeration of nanoparticles Moreover permeation of CO2 and N2 through PEI TiO2 membranes was higher than pure PEImembrane In addition for PEI TiO2 membranes with 1 and 2 of TiO2 CO2 N2 ideal selectivitywere increased whereas for the membrane with 5 TiO2 the selectivity decreased due toagglomeration of nanoparticles and the presence of defect in the selective layer of the membrane Also prepared membranes were characterized by SEM FTIR XRD TG and DMT analyses Keywords Membrane Glassy polymer Gas separation Permeability Selectivity Plasticization

علي كبر دادخواه، عبداللطيف هاشمي فرد

مرتضي صادقي، اميرحسين نوارچيان، محمد ديناري