مطالعه و بررسي اثر ذرات زئوليت بر عملكرد جداسازي گاز با استفاده از غشاي پلي يورتاني

چكيده انگليسي :

Study and Investigation of the Effect of Zeolite Particles on the Gas Separation Performance of Polyurethane Mixed Matrix Membranes Hajar Taheri Afarani h taheriafarani@ce iut ac ir Date of Submission 2012 03 3 Department of Chemical Engineering IsfahanUniversity of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisors Morteza Sadeghi m sadeghi@cc iut ac ir Ahmad Moheb ahmad@ce iut ac irAbstractThe use of membranes for separation and purification of gases vapors and process liquids compared to othertechnologies such as absorption and distillation known attractive process for oil gas and petrochemicalindustries Because the membrane technology are low cost low power consumption In terms of energy andcompatible with the environment In this study a group of polyurethane based on hard segments containing oftoluene diisocyanate TDI and 1 4 butane diamine BDA and soft segment consisting ofpolypropyleneglycol PPG with molecular weight 2000 g molewere synthesized The polymer was synthesized in moleratios of 1 3 2 of diisocyanate chain extender polyol by bulk two step polymerization To investigate theeffect of zeolite particles on permeability properties of polyurethane and improve it mixed matrix densemembranes of polyurethane zeolite were prepared by using thermal phase inversion method and evaluatedpure gas permeability of nitrogen oxygen methane and carbone dioxideat constant temperature and pressure To study the effect of zeolite type on the performance of gas separation membrane the permeability ofpolyurethane zeolite 3A 4A and ZSM 5 wereinvestigated The permeability of nitrogen oxygen methaneand carbon dioxide were determined using constant pressure method In order to make meaningful tests andobtain process optimization response surface design and analysis by design expert6 software and centralcomposite design CCD was used Zeolite concentration temperature and pressure were selected as the mainparameters and in the 0 24wt 25 45 C and 2 10 bar regions respectively The results of analysis showedthat the effect of increasing zeolite concentration was more influence Also the optimal operatingconditionsare in the area between of defined ranges By using design expert6 software optimal points of parameters areachieved in zeolite concentration 18wt temperature 30 C and pressure8bar As it was expected withincreasing the temperature not only the permeability of all gases was increased especially for morecondensable gases this increase with higher intensity were visible but also all the selectivities were decreased It was observed that with increasing the pressure selectivities increased The prepared polyurethane zeolitemembranes were characterized using FTIR and SEM The obtained SEM micrographs and FT IR spectrasconfirmed that the zeolite particles distributed in polymer matrix homogenously Gas permeation propertiesof polyurethane zeolite mixed matrix membranes with zeolite content of 6 12 18 and 24 wt was studiedfor pure gases at 10 bar pressure and at 25 C Increasing the zeolite particles from 0 to 24 wt inpolyurethane increased permeability and selectivity coefficient for all three types of polyurethane zeolitemixed matrix membranes in compared with pure polyurethane membrane The results of gas permeationexperiments represented that polyurethane zeolite 4A is the most suitable membrane because of the pore sizeof zeolite 4A Because zeolite 4A pore size was appropriate for the separation of selected gases ThePermeability of condensable gases in comparison to non condensable ones more increase by increasing thezeolite content in polymer Structure Also the selectivity of condensable gases in polyurethane considerablyincreased The permeability of CO2 and itsselectivity over N2 was increased from 69 01barrer and 16 36inpure polyurethane to 95 81barrer and 22 08in thezeolite3A mixed matrix membrane containing 24wt ofzeolite particles The permeability of CO2 and itsselectivity over N2 was increased from 69 01 barrer and16 36

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مطالعه و بررسي اثر ذرات زئوليت بر عملكرد جداسازي گاز با استفاده از غشاي پلي يورتاني

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