78 International Journal of Membrane Science and Technology, 2015, 2, 78-84 E-ISSN: 2410-1869/15 © 2015 Cosmos Scholars Publishing House Development of PEBAX Based Membrane for Gas Separation: A Review M.S. Abdul Wahab and A.R. Sunarti * Faculty of Chemical & Natural Resources Engineering, Universiti Malaysia Pahang, Gambang, Pahang, MALAYSIA Abstract: Polymer is among the favorite materials used for membrane separation as they are cheap, easily cast, low maintenance cost and commercially easy to get eventhough the material needs to be altered to meet the separation industry specific needs. There are two common issues in membrane preparation which are the produced sheet are too brittle and has no strength to withstand pressure during separation process and the porosity of the sheet sometimes not suitable with the gas kinetic diameter for the separation to occur. PEBAX or Poly ether block amide is the answer for the issues as this elastomer provides good mechanical strength from the hard segment of the crystalline poly amide block while the soft polyether will drive the separation process. This unique material can be casted either by phase inversion of the PEBAX itself with other polymer or by coating them on the other polymer substrate. Key words: PEBAX, Composite membrane, Substrate, Elastomer. INTRODUCTION Methane, a key component in natural gas composition has a wide availability. Contributing 75% of natural gas, these energy resources also can be obtained from biomass. The waste that can easily transformed into wealth have a bright future as a new way of creating energy. It is estimated that 25% of renewable energy in 2020 will be from biogas [1]. The decomposition of waste through anaerobic digestion of bacteria will produced biogas which contain methane in a natural way. The presence of 50-60 % methane is biogas composition are the major interest of the biomass [2-4]. Current method used for purification of methane from carbon dioxide are by water scrubbing[5], Polyethylene glycol scrubbing[6], carbon molecular sieves [7] and the popular membrane separation [8]. In natural gas processing membrane separation practically used as they offer low energy cost, high efficiency and low pollution [9]. It is usually employed to separate carbon dioxide, nitrogen, hydrogen sulfide and others from natural gas. Other technology in gas separation technology such cryogenic separation, absorption/adsorption separation, and supersonic separation. Despite all the high technology separation process, membrane separation has took a central stage in research arena as they are the alternative for a same purpose but with simple process [10]. * Address correspondence to this author at the Faculty of Chemical & Natural Resources Engineering, Universiti Malaysia Pahang, Gambang, Pahang, MALAYSIA; Tel: +609‐5492822; Fax: +609‐5492889; Email: sunarti@ump.edu.my; sunartirahman@gmail.com Polymeric membrane offer an energy efficient with low capital cost, flexible process, ease of scale up and high efficient of raw material [11-14].Various polymer has been used as based material, mixing and coating altogether to achieve desired need of gas separation. PES [15], PVDF [16], PVC [17], and PSF [18] are among the top polymer in this field of research. Every each of these polymers has their own ability to separate only limited kind of species. This review paper will focus on preparation of dope solution and casting technique of PEBAX 1657 and PEBAX 2533 toward a perfect flat sheet membrane for gas separation. The modification of PEBAX membrane that leads to a perfect selective layer and method used to avoid gelation of PEBAX solution. PEBAX A NEW ITERATION IN MEMBRANE DEVELOPMENT PEBAX or poly (ether block amide) is a family of copolymers, consisting of polyamide hard segments and polyether soft segments in the long polymeric chains [19].The hard amide block will put the material on the mechanical strength stability and the soft segment of polyether will primarily drive the separation process. These unique structures have made PEBAX a good chemical resistance towards acid, basic and organic solvents and high thermal and mechanical stabilities. In several studies, PEBAX has shown an excellent result for CO 2 separation due to their polar ether oxygen withCO 2 interaction with other non-polar gases [20]. There are two common type of PEBAX used in industry, PEBAX 1657 and PEBAX 2533.The PEBAX composition is tabulated in Table 1 [20, 21]. Bernardo