Novel Polydimethylsiloxane membranes impregnated with SAPO-34 zeolite particles for gas separation
9
Citation
70
Reference
10
Related Paper
Citation Trend
Keywords:
Polydimethylsiloxane
Two tailor-made microporous metal–organic framework (MOF) membranes were successfully fabricated on nickel screens by secondary growth. The effect of pore structures on gas separation was examined by means of single and binary gas permeation tests. The MOF JUC-150 membrane with its ultra-micropores showed marked preferential permeance to H2 relative to other gas molecules. The selectivity factors of this membrane were 26.3, 17.1 and 38.7 for H2/CH4, H2/N2 and H2/CO2, respectively, at room temperature. To the best of our knowledge, these values represent unprecedentedly high separation selectivity among those for all MOF membranes reported to date. The JUC-150 membrane also shows high thermal stability and outstanding separation performance at a high temperature of 200 °C. The separation performance of these membranes persists even after more than 1 year exposure to air. The superiority of the tailored pore size, high selectivity for H2 over other gases, significant stability and recyclability make these materials potential candidates for industrial H2 recycling applications.
Permeance
Thermal Stability
Membrane Technology
Cite
Citations (140)
Abstract Continuous microporous membranes are widely studied for gas separation, due to their low energy premium and strong molecular specificity. Porous aromatic frameworks (PAFs) with their exceptional stability and structural flexibility are suited to a wide range of separations. Main‐stream PAF‐based membranes are usually prepared with polymeric matrices, but their discrete entities and boundary defects weaken their selectivity and permeability. The synthesis of continuous PAF membranes is still a major challenge because PAFs are insoluble. Herein, we successfully synthesized a continuous PAF membrane for gas separation. Both pore size and chemistry of the PAF membrane were modified by ion‐exchange, resulting in good selectivity and permeance for the gas mixtures H 2 /N 2 and CO 2 /N 2 . The membrane with Br − as a counter ion in the framework exhibited a H 2 /N 2 selectivity of 72.7 with a H 2 permeance of 51844 gas permeation units (GPU). When the counter ions were replaced by BF 4 − , the membrane showed a CO 2 permeance of 23058 GPU, and an optimized CO 2 /N 2 selectivity of 60.0. Our results show that continuous PAF membranes with modifiable pores are promising for various gas separation situations.
Permeance
Facilitated Diffusion
Cite
Citations (2)
Polydimethylsiloxane
Cite
Citations (106)
Surface Modification
Cite
Citations (15)
Continuous microporous membranes are widely studied for gas separation, due to their low energy premium and strong molecular specificity. Porous aromatic frameworks (PAFs) with their exceptional stability and structural flexibility are suited to a wide range of separations. Main-stream PAF-based membranes are usually prepared with polymeric matrices, but their discrete entities and boundary defects weaken their selectivity and permeability. The synthesis of continuous PAF membranes is still a major challenge because PAFs are insoluble. Herein, we successfully synthesized a continuous PAF membrane for gas separation. Both pore size and chemistry of the PAF membrane were modified by ion-exchange, resulting in good selectivity and permeance for the gas mixtures H2 /N2 and CO2 /N2 . The membrane with Br- as a counter ion in the framework exhibited a H2 /N2 selectivity of 72.7 with a H2 permeance of 51844 gas permeation units (GPU). When the counter ions were replaced by BF4- , the membrane showed a CO2 permeance of 23058 GPU, and an optimized CO2 /N2 selectivity of 60.0. Our results show that continuous PAF membranes with modifiable pores are promising for various gas separation situations.
Permeance
Facilitated Diffusion
Cite
Citations (50)
Selectivity and permeability are two significant parameters in the gas separation process. Hence, nowadays, modification of membrane to improve the parameters mentioned above, have highly gained attention. In this study, to increase the performance of the polymeric membrane, bare ZIF-8 nanoparticle (NP), as well as annealed and NH2 -functionalized ones (Medium-sized particles less than 100 nm), were introduced into the structure of polydimethylsiloxane (PDMS) top layer at different concentrations. The high porosity and gas adsorption characteristics of the ZIF-8 made it a proper nanofiller to modify and improve the efficiency of polymeric membranes. The CO2 /N2 and O2 /N2 selectivity of the membranes improved regarding the loading ZIF-8. In addition, NH2 -functionalized and thermal annealed ZIF-8s employed to compare the result of the treated NPs on the efficiency of the fabricated MMMs. Consequently, the selectivity of both mentioned pair gases improved. At 2 wt% of annealed ZIF-8s, the mixed matrix membrane (MMM) presents a desired separation selectivity over 5.5 and 22.37 for O2 /N2 and CO2 /N2 , respectively.
Polydimethylsiloxane
Cite
Citations (5)
Pervaporation
Polydimethylsiloxane
Cite
Citations (233)
The beta zeolite membranes were prepared on seeded α-Al2O3 substrate tubes with a mean pore size of 3-5 μm by the method of secondary hydrothermal growth using TEAOH as templates.The prepared membranes were characterized with XRD,SEM and nitrogen permeance.XRD patterns show that the prepared membranes possess typical beta zeolite structure.SEM images indicated that a continuous and dense zeolite membrane with around 10 μm in thickness is formed on the seeded supports.Nitrogen permeation experiments proved that the permeation governed by surface diffusion.Thus the prepared membranes have no large defects.
Permeance
Hydrothermal Synthesis
Cite
Citations (0)
Pervaporation
Cite
Citations (83)
In this study, preparation and simulation of polydimethylsiloxane (PDMS) membranes for gas separation is carried out. The membranes are synthesized by solution‐casting method via silicon oil as precursor. Gas permeation experiments for single gases of CH 4 and N 2 were conducted at different feed pressures (2–10 bars). PDMS membrane as a rubbery polymer showed that are more permeable toward more condensable gases, i.e., CH 4 compared to N 2 . It was indicated that increasing feed pressure enhances permeability of CH 4 through the membrane slightly, but the permeability of nitrogen was almost constant over enhancement of feed pressure. Moreover, a mathematical model was developed to predict the permeation of gases across PDMS membrane. The model is based on solving conservation equations for gases in the membrane phase. Finite element analysis was utilized for numerical simulation of the governing equations. The simulation results were used to predict the concentration of gases inside the membrane. POLYM. ENG. SCI., 55:54–59, 2015. © 2014 Society of Plastics Engineers
Polydimethylsiloxane
Cite
Citations (3)