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JOURNALOFNATURALGASCHEMISTRY212012282298REVIEWCONVENTIONALPROCESSESANDMEMBRANETECHNOLOGYFORCARBONDIOXIDEREMOVALFROMNATURALGASAREVIEWZEEYINGYEO1,THIAMLENGCHEW2,PENGWEIZHU1,ABDULRAHMANMOHAMED3,SIANGPIAOCHAI11CHEMICALENGINEERINGDISCIPLINE,SCHOOLOFENGINEERING,MONASHUNIVERSITY,46150BANDARSUNWAY,SELANGOR,MALAYSIA2FACULTYOFENGINEERINGANDGREENTECHNOLOGYFEGT,PERAKCAMPUS,UNIVERSITITUNKUABDULRAHMAN,JALANUNIVERSITI,BANDARBARAT,31900KAMPAR,PERAK,MALAYSIA3SCHOOLOFCHEMICALENGINEERING,ENGINEERINGCAMPUS,UNIVERSITISAINSMALAYSIA,SERIAMPANGAN,14300NIBONGTEBAL,PENANG,MALAYSIAMANUSCRIPTRECEIVEDJANUARY11,2012REVISEDFEBRUARY28,2012ABSTRACTMEMBRANETECHNOLOGYISBECOMINGMOREIMPORTANTFORCO2SEPARATIONFROMNATURALGASINTHENEWERADUETOITSPROCESSSIMPLICITY,RELATIVEEASEOFOPERATIONANDCONTROL,COMPACT,ANDEASYTOSCALEUPASCOMPAREDWITHCONVENTIONALPROCESSESCONVENTIONALPROCESSESSUCHASABSORPTIONANDADSORPTIONFORCO2SEPARATIONFROMNATURALGASAREGENERALLYMOREENERGYDEMANDINGANDCOSTLYFORBOTHOPERATIONANDMAINTENANCEPOLYMERICMEMBRANESARETHECURRENTCOMMERCIALMEMBRANESUSEDFORCO2SEPARATIONFROMNATURALGASHOWEVER,POLYMERICMEMBRANESPOSSESSDRAWBACKSSUCHASLOWPERMEABILITYANDSELECTIVITY,PLASTICIZATIONATHIGHTEMPERATURES,ASWELLASINSUFFICIENTTHERMALANDCHEMICALSTABILITYTHESHORTCOMINGSOFCOMMERCIALPOLYMERICMEMBRANESHAVEMOTIVATEDRESEARCHERSTOOPTFOROTHERALTERNATIVES,ESPECIALLYINORGANICMEMBRANESDUETOTHEIRHIGHERTHERMALSTABILITY,GOODCHEMICALRESISTANCETOSOLVENTS,HIGHMECHANICALSTRENGTHANDLONGLIFETIMESURFACEMODIFICATIONSCANBEUTILIZEDININORGANICMEMBRANESTOFURTHERENHANCETHESELECTIVITY,PERMEABILITYORCATALYTICACTIVITIESOFTHEMEMBRANETHISPAPERISTOPROVIDEACOMPREHENSIVEREVIEWONGASSEPARATION,COMPARINGMEMBRANETECHNOLOGYWITHOTHERCONVENTIONALMETHODSOFRECOVERINGCO2FROMNATURALGAS,CHALLENGESOFCURRENTCOMMERCIALPOLYMERICMEMBRANESANDINORGANICMEMBRANESFORCO2REMOVALANDMEMBRANESURFACEMODIFICATIONFORIMPROVEDSELECTIVITYKEYWORDSMEMBRANETECHNOLOGYINORGANICMEMBRANECO2SEPARATIONNATURALGASSURFACEMODIFICATIONZEEYINGYEOPHDSTUDENTATCHEMICALENGINEERINGDISCIPLINE,SCHOOLOFENGINEERING,MONASHUNIVERSITYSUNWAYCAMPUSSHEISWORKINGONINORGANICANDFUNCTIONALMEMBRANESFORCARBONDIOXIDESEPARATIONTHIAMLENGCHEWASSISTANTPROFESSOROFTHEFACULTYOFENGINEERINGANDGREENTECHNOLOGY,UNIVERSITITUNKUABDULRAHMAN,MALAYSIAHERECEIVEDHISPHDDEGREEINCHEMICALENGINEERINGIN2012HISRESEARCHINTERESTSFOCUSONTHEAREASOFTHESEPARATIONOFCARBONDIOXIDEUSINGINORGANICANDFUNCTIONALMEMBRANESANDDEVELOPMENTOFZEOLITEMATERIALSCORRESPONDINGAUTHORTEL60355146234FAX60355146207EMAILCHAISIANGPIAOMONASHEDUSPCHAITHISWORKWASSUPPORTEDBYTHEMINISTRYOFHIGHEREDUCATIONMALAYSIATHROUGHLONGTERMRESEARCHGRANTSCHEMEA/CNUMBER211022611300COPYRIGHT2012,DALIANINSTITUTEOFCHEMICALPHYSICS,CHINESEACADEMYOFSCIENCESALLRIGHTSRESERVEDDOI101016/S1003995311603666JOURNALOFNATURALGASCHEMISTRYVOL21NO32012283PENGWEIZHUASSOCIATEPROFESSOROFTHESCHOOLOFENGINEERING,MONASHUNIVERSITYSUNWAYCAMPUSHERECEIVEDHISPHDDEGREEINCHEMISTRYIN1994HISMAINRESEARCHINTERESTSAREINFUNCTIONALCOLLOIDS,SURFACTANTSANDEMULSIONS,STIMULIRESPONSIVE/FUNCTIONALMATERIALS,INTERFACIALCONFORMATIONSANDRELEVANTPHENOMENA,NONEQUILIBRIUMANDRELAXATIONSATSURFACES/INTERFACESABDULRAHMANMOHAMEDPROFESSOROFTHESCHOOLOFCHEMICALENGINEERINGANDDIRECTOROFTHECENTREFORENGINEERINGEXCELLENCE,UNIVERSITISAINSMALAYSIAHERECEIVEDHISPHDDEGREEINCHEMICALENGINEERINGIN1993HISRESEARCHINTERESTSFOCUSONREACTIONENGINEERINGANDCATALYSIS,AIRPOLLUTIONANDWASTEWATERCONTROLENGINEERING,FUELTECHNOLOGY,NANOSCIENCEANDNANOTECHNOLOGYSIANGPIAOCHAISENIORLECTUREROFTHESCHOOLOFENGINEERING,MONASHUNIVERSITYSUNWAYCAMPUSHERECEIVEDHISPHDDEGREEINCHEMICALENGINEERINGIN2008HISMAINRESEARCHINTERESTSAREINTHEAREASOFCATALYSISANDREACTIONENGINEERING,MEMBRANETECHNOLOGY,NATURALGASPROCESSINGANDNANOMATERIALSDEVELOPMENT1INTRODUCTION11CO2INNATURALGASTHEREHASBEENINCREASINGDEMANDFORTHEUSEOFNATURALGASASAMOREEFFICIENTANDCLEANERFUELNATURALGASISALSOCONSIDEREDASTHEPRINCIPALFEEDSTOCKFORTHECHEMICALINDUSTRYTHEGLOBALCONSUMPTIONOFNATURALGASISPROJECTEDTOINCREASEFROM95TRILLIONCUBICFEETIN2003TO182TRILLIONCUBICFEETIN20301THECONSUMPTIONOFNATURALGASINTHEUNITEDSTATESISEQUIVALENTTO22TRILLIONCUBICFEETPERYEAR2WHILETHEESTIMATEFORTHENATURALGASCONSUMPTIONINEUROPEANUNIONIS522BILLIONCUBICMETERS3NATURALGASRESERVESINMALAYSIASTOODAT88TRILLIONCUBICFEETASAT1STJANUARY2008,WHICHISTHREETIMESTHATOFCRUDEOILOF546BILLIONBARRELOFTHIS,38ISFOUNDOFFTHEEASTCOASTOFPENINSULARMALAYSIA,48ATOFFSHORESARAWAK,AND14REMAININGATOFFSHORESABAHMALAYSIASGASRESERVESAREEXPECTEDTOLASTFORANOTHER36YEARSWITHCURRENTRATEOFPRODUCTION4CURRENTLY,THEWORLDWIDEMARKETFORNEWNATURALGASSEPARATIONEQUIPMENTCONSUMES5BILLIONPERYEAR,HOWEVER,MEMBRANEPROCESSESONLYHAVELESSTHAN10TOTAL100WATER10000PPMTOTAL100C3CONTENT9501050BTU/SCFDEWPOINT4284ZEEYINGYEOETAL/JOURNALOFNATURALGASCHEMISTRYVOL21NO32012FIGURE1RESERVESTOPRODUCTIONR/PRATIOSOFNATURALGAS5IN2010BYREGIONACIDGASESLIKEH2SANDCO2INNATURALGASWELLSTREAMSHAVENOHEATINGVALUE,ANDTHEYFORMACIDSORACIDICSOLUTIONSINTHEPRESENCEOFWATERWHICHARECORROSIVETHEREMOVALOFCO2ISVERYIMPORTANTASITISONEOFTHEMOSTCOMMONCONTAMINANTSACIDGASESCONTENTCOULDREACHANDEVENOVERPASS50VOLUMEINSOMEUNCONVENTION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