Dzeti Farhah Mohshim

Latest Development on Membrane Fabrication for Natural Gas Purification: A Review

In the last few decades, membrane technology has been a great attention for gas separation technology especially for natural gas sweetening. The intrinsic character of membranes makes them fit for process escalation, and this versatility could be the significant factor to induce membrane technology in most gas separation areas. Membranes were synthesized with various materials which depended on the applications. The fabrication of polymeric membrane was one of the fastest growing fields of membrane technology. However, polymeric membranes could not meet the separation performances required especially in high operating pressure due to deficiencies problem. The chemistry and structure of support materials like inorganic membranes were also one of the focus areas when inorganic membranes showed some positive results towards gas separation. However, the materials are somewhat lacking to meet the separation performance requirement. Mixed matrix membrane (MMM) which is comprising polymeric and inorganic membranes presents an interesting approach for enhancing the separation performance. Nevertheless, MMM is yet to be commercialized as the material combinations are still in the research stage. This paper highlights the potential promising areas of research in gas separation by taking into account the material selections and the addition of a third component for conventional MMM.

Surface modification in inorganic filler of mixed matrix membrane for enhancing the gas separation performance

Abstract The development of mixed matrix membrane (MMM) in gas separation process has drawn great attention due to its promising properties. MMM consists of a polymer as the matrix phase, whereas the inorganic filler serves as the dispersed phase. However, poor contact between these two phases often results in unselective gas flow and becomes one of the major issues in the MMM development. Currently, various modification techniques of the inorganic filler to improve the compatibility between the polymers and the particles have been reported. Because of this modification, the CO2 separation from natural gas is expected to enhance. This review provides a better understanding about the modification of inorganic filler. Mechanisms and factors affecting the modification of filler such as the effect of solvent polarity, the effect of water content in solvent, and the effect of drying condition are discussed. The details of the current progress in the MMM involving the silane-modified fillers are also summarized.

Ionic Liquid Polymeric Membrane: Synthesis, Characterization & Performance Evaluation

Selected ionic liquids are known to enhance the absorption of CO2 for CO2 removal purpose. In the idea to improve the membrane separation performance for natural gas sweetening, ionic liquid modified polymeric membranes were fabricated by using polyethersulfone (PES) and blended with different composition of ionic liquid which are 5 wt% and 15 wt%. Each fabricated membranes were prepared and dried under solvent evaporation at 90°C. Dense structure observed from FESEM analysis indicated the miscible blends of ionic liquid and PES. TGA analysis showed all fabricated membranes are still containing solvent and this resembles that membrane drying period is still insufficient. All fabricated membranes were tested with ideal gas permeation test. From the result, the addition of ionic liquid has enhanced the ideal CO2 pemeance about 150% as compared to pure PES membrane. The ideal CO2/CH4 selectivity was also increase about 85% from the base but however, the separation index is still considered low and this may due to the presence of the solvent. This preliminary result has confirmed that the blending of ionic liquid with pure PES membrane has technically improved the membrane separation performance.

Effects of Ionic Liquid Blending in Polymeric Membrane: Physical Properties and Performance Evaluation

— Polymeric membranes have been extensively used in membrane gas separation process. Nowadays, peoples are modifying the membrane by many ways like coating with ionic liquids to further enhance the membrane separation performance. In this project, ionic liquid modified polymeric membranes (ILMPM) have been successfully developed by blending the ionic liquids with the polymer via solvent evaporation method. The ionic liquid used was 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, ([emim][Tf2N]) and for comparison purpose, the compositions were varied at 10 and 20 wt/wt%. In general, the blending of [emim][Tf2N] and PES has produced dense membrane with miscible mixture without any phase separation. It was observed that, the CO2 permeance of ILMPM has been improved about 271% as compared to the pure PES membrane. However, the CO2 permeance decreased with increasing operating pressure, yet the ILMPM CO2 permeance still higher than CO2 permeance of pure PES membrane. In addition, the CO2/CH4 separation performance has greatly increased about 162% as the IL composition is increased. This initial study has proven that IL helps to enhance of CO2 permeation and improve selectivity.