The polymeric upper bound for N2/NF3 separation and beyond; ZIF-8 containing mixed matrix membranes.

Global production for NF 3 is continuously increasing, especially due to its heavy consumption in the semiconductor industry. Even though the amount of its emission is relatively small compared to other greenhouse gases, particularly CO 2 , the relatively long atmospheric lifetime of NF 3 makes its emission cumulative, possibly contributing to the global climate change. Membrane-based separation techniques are very promising for the energy-efficient NF 3 recovery. It is, therefore, critically important to evaluate the N 2 /NF 3 separation performance by using commercial polymeric membranes. Here, for the first time, the empirical N 2 /NF 3 upper bound relationship is established by using a wide variety of commercial polymeric membranes including both glassy and rubbery polymers based on their single gas (i.e. N 2 and NF 3 ) permeation characterization. Among those tested, 6FDA–DAM:DABA (3:2), Teflon ® AF 2400 and PTMSP exhibited relatively high N 2 /NF 3 separation performance. The theoretical N 2 /NF 3 upper bound curve was also defined and found comparable with our empirical upper bound limit. In an effort to improve the N 2 /NF 3 separation performance, mixed matrix membranes were prepared by incorporating zeolitic imidazolate framework molecular sieves into Matrimid ® 5218. The effects of solvents, particle sizes, and ligands on the transport properties in mixed matrix membranes were investigated. [ABSTRACT FROM AUTHOR]