Effect of humidity and flue gas impurities on CO2 permeation of a polymer of intrinsic microporosity for post-combustion capture

Abstract

The impact of humidity and flue gas impurities on PIM-1 membrane performance for post combustion capture, i.e. CO2 permeability and CO2/N2 selectivity, is investigated in this study. The presence of humidity in the feed stream induces a decrease in the permeability coefficients of both CO2 and N2, from 7010 Barrer (dry state) to 4135 Barrer (%RH=50%) and 360 Barrer (dry state) to 250 Barrer (%RH=50%) respectively. PIM-1 shows also a high water permeability (58800 Barrer) which increases with the relative humidity of the feed. The interaction with flue gas contaminants (NOx, SOx, Water) leads to a dramatic decrease of the membrane performance even after short exposure and FTIR analysis confirmed modifications of the chemical structure of PIM-1 caused by the acid environment. These results indicate that test with flue gases have to be considered for all novel materials proposed for carbon capture applications since the decrease in membrane permeability in presence of water and other impurities has to be taken into account during the design of the separation process.

Effect of relative humidity on the gas transport properties of zeolite A/PTMSP mixed matrix membranes

“…Regarding the water effect, the gas permeability through PTMSP membranes generally decreased with increasing water activity for all gases investigated, in agreement with other polyimide membranes made of PIM-1 21,32 or Matrimid, 29 due to the reduction in diffusivity when water molecules occupy part of the free volume of the polymer. The gas permeability through the zeolite A/PTMSP MMM also decreased for N 2 and CH 4 with increasing water activity, while the CO 2 permeability showed a slight increase to about 50% RH, followed by a slight decrease.…”

Advanced Membranes and Learning Scale Required for Cost-Effective Post-combustion Carbon Capture

“…In addition, the presence of humidity and minor air pollutants in flue gas likely affect the gas transport properties. In general, the competitive sorption of water, sulfur oxides, and nitrogen oxides decreases both the CO 2 permeability and selectivity for glassy polymers when compared with the pure gas case, whereas the gas permeability increases strongly with water vapor activity for rubbery polymers due to the membrane swelling by water ( Lasseuguette et al., 2016 , Kanehashi et al., 2015 ). Large-scale pilot and demonstration projects are needed to rigorously examine the performance of advanced membranes under harsh conditions.…”

Top-Down Polyelectrolytes for Membrane-Based Post-Combustion CO2 Capture

“…Versatile chemical structures of these polymers provides increased CO 2 solubility in the polymer matrix, and tailored chain packing density ensures faster diffusion rates through the selective layer [14,15]. Many alternative membrane concepts emerged based on polymers of intrinsic micro-porosity [16][17][18], thermally-rearranged polymers [19][20][21][22], organic/inorganic hybrid materials (mixed matrix membranes) [23][24][25][26], or facilitated transport materials [27][28][29][30]. Their advantages and disadvantages in membrane-based CO 2 capture are summarised in Table 1.…”