Highly Permeable Mixed Matrix Hollow Fiber Membrane as a Latent Route for Hydrogen Purification from Hydrocarbons/Carbon Dioxide

Abstract

This work reported on the fabrication and investigation of a mixed matrix hollow fiber membrane (MMHFM) by incorporating commercially available alumina particles into a polyetherimide (PEI) polymer matrix. These MMHFMs were prepared by the dry-wet spinning technique. Accordingly, optimizing the spinning parameters, including the air gap distance and flow rate ratio, is key to determining the gas separation performance. However, there are few studies regarding the effect of the filler dimensions. Consequently, three sizes of alumina particles, 20 nm, 30 nm, and 1000 nm, were respectively added into the PEI phase to examine the influence of filler size on gas permeation property. Moreover, the permeation properties of lower hydrocarbons (i.e., ethane and propane) were also measured to evaluate potential for emerging applications. The results indicated the as-synthesized membrane exhibited a remarkable hydrogen permeance of 1065.24 GPU, and relatively high separation factors of 4.53, 5.77, and 5.39 for H2/CO2, H2/C2H6, and H2/C3H8, respectively. This resulted from good compatibility between the larger fillers and the PEI polymer, as well as a reduction in the finger-like voids. Overall, the MMHFM in this work was deemed to be a promising candidate to separate hydrogen from gas streams, based on the comparison of the separation performance against other reported studies.

Annealing and TMOS coating on PSF/ZTC mixed matrix membrane for enhanced CO 2 /CH 4 and H 2 /CH 4 separation

“…Different TMOS coating concentrations (0.01 and 0.05 mol) on annealed MMM exhibited low CO 2 /CH 4 selectivity, namely 1.00 and 0.93, respectively. The low selectivity (similar to CO 2 /CH 4 Knudsen selectivity of 0.6) indicates that the major gas diffusion contributor is Knudsen diffusion, in which the gas permeance is inversely related to the molecular weight of the penetrated species [64]. Furthermore, gas diffusion is influenced by the mean free path length, which is the average distance travelled by a gas molecule before colliding with another gas molecule [65].…”

Performance Comparison of Cross- and Forward-Flow Configurations for Multiple-Effect Vacuum Membrane Distillation

“…Another pioneering idea is using the heat pump system to preheat the feed stream by leveraging the heat rejected from the heat pump system through the condenser, as explained in [ 10 , 19 ]. Moreover, the development of the efficiency of fabricated membranes is one of the important factors that played a positive role in improving the distillation process, as reported in previous works [ 20 , 21 ].…”