High performance polybenzimidazole based asymmetric hollow fibre membranes for H2/CO2 separation

Synthesis, characterization and evaluation of porous polybenzimidazole materials for CO2 adsorption at high pressures

“…Figure 2 shows FTIR analysis of PBI materials crosslinked by two different cross-linking agents TMA and NTA represented as PBI-1 and PBI-2 respectively. FTIR spectra shows strong absorption in the benzimidazole ring region (1438-1631 cm -1 ) (Valtcheva et al 2014), which is the characteristic absorption of in-plane vibration and combined C=C, C=N ring vibration (Kumbharkar et al 2011). The broad peak absorption between 2809 and 3450 cm -1 is attributed to N-H asymmetric stretching (Bhadra et al 2010), absorption at 798 and 877 cm -1 could be assigned to C-H (Kang et al 2013) out of plane bending and peaks at 1282 cm -1 comes from breathing mode of benzimidazole (Suryani et al 2011).…”

“…The significant variation in morphology of the two polymers may be attributed to the solvents effect on the nucleation and agglomeration of the materials. Since PPA is more viscous than concentrated HCl, thus it may slow down the agglomeration and coagulation process during synthesis (Wang and Chung 2006;Kumbharkar et al 2011). Figure 6 shows nitrogen up take isotherms of PBI-2 and PBI-1 materials having type-III characteristics with a visible hysteresis suggesting macro-porosity and amorphous nature of these materials (Zhang et al 2014).…”

Influence of solvent exchange time on mixed matrix membrane separation performance for CO2/N2 and a kinetic sorption study

“…The water was replaced with ethanol followed by hexane to minimize the capillary forces inside of the pore [7] and to reduce the surface tension during the drying process. Consequently, the structure of the CA membrane did not collapse [8].…”

“…The water was replaced with ethanol followed by hexane to minimize the capillary forces inside of the pore [7] and to reduce the surface tension during the drying process. Consequently, the structure of the CA membrane did not collapse [8].Generally, the synthesized membrane must be dried before using for gas separation [7].Thus, one challenge encountered in this study was drying the newly synthesized MMMs without causing any structure rupture. In fact, the water contained within the CA membrane is difficult to remove because of its asymmetric structure [7].…”

Recent developments in membranes for efficient hydrogen purification

“…Therefore, a balance between permeability and selectivity is necessary in the light It should be noted that PBI is not well soluble in common organic solvents such as methanol, acetone, tetrahydrofuran and dimethylformamide at room temperature, which restricts the preparation of composite membranes on conventional polymeric supports via solution coating, thereby the fabrication cost of PBI composite membranes may be not economically attractive. To circumvent this problem, PBI-based asymmetric hollow fiber membranes were developed via traditional dry-jet wet spinning technique[148]. The resultant…”