New PEEK-WC and PLA membranes for H2 separation

The potentialities of PEEK-WC (thermally treated at 120 degrees C) and PLA polymers have been studied in the field of membrane technology applied to H-2 separation/purification. In particular, for low/medium temperature operation (80 degrees C), PEEK-WC membranes (66 mu m thick) showed good results in terms of H-2/CH4 separation, showing an ideal selectivity value higher than 40. Meanwhile, we observed interesting selectivity also for H-2/N-2 and H-2/ CO2 separation, reaching values of 24 and 20, respectively. As expected, for PEEK-WC thermally treated membranes, the H-2 permeating flux increased from 25 to 80 degrees C and by increasing the transmembrane pressure. Furthermore, H-2 permeability at 80 degrees C was around 20 barrer. Concerning PLA membranes (26 mu m thick), it is worth of noting that this polymer was pioneeristically used in this work as membrane application, showing great results in terms of H-2/CO2 separation. Indeed, we overcame the Robeson's upper-bound (2008), achieving an ideal selectivity H-2/CO2 around 25 with an H-2 permeability of 25 barrer. Further advantage due to the utilization of PLA membranes was related to the temperature operations set at ambient conditions, constituting a valuable and cost-effective solution for H-2/CO2 separation processes via polymeric membrane technology. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.