ZIF-8 Membranes via Interfacial Microfluidic Processing in Polymeric Hollow Fibers: Efficient Propylene Separation At Elevated Pressures
Propylene/propane (C3H6/C3H8) separations are performed on a large scale by energy-intensive distillation processes. Membranes based on metal-organic framework (MOF) molecular sieves, such as zeolitic imidazolate framework-8 (ZIF-8), offer the potential to perform these separations at considerably lower cost. However, the fabrication of scalable ZIF-8 membranes with high performance at elevated pressures and temperatures is challenging. We report the fabrication of high-quality ZIF-8 hollow fiber membranes in engineered polymeric hollow fibers via the interfacial microfluidic membrane processing (IMMP) technique. Control of fiber microstructure, as well as optimization of IMMP conditions, allow us to achieve a C3H6/C3H8 separation factor of 180 (at 1 bar and 25 °C), which remains high (60) at 120 °C. Furthermore, high-pressure operation of these membranes was investigated. Detailed permeation measurements indicate excellent suppression of defects at higher pressures up to 9.5 bar, allowing a C3H6/C3H8 separation factor of 90 at 9.5 bar. The membranes also display a 4-fold increase in flux at 9.5 bar as compared to operation at 1 bar. The long-term stability of the ZIF-8 hollow fiber membranes is demonstrated by continuous operation over a month without loss of C3H6 permeance or selectivity.
K. Eum et al., "ZIF-8 Membranes via Interfacial Microfluidic Processing in Polymeric Hollow Fibers: Efficient Propylene Separation At Elevated Pressures," ACS Applied Materials and Interfaces, vol. 8, no. 38, pp. 25337-25342, American Chemical Society (ACS), Sep 2016.
The definitive version is available at https://doi.org/10.1021/acsami.6b08801
Chemical and Biochemical Engineering
Phillips 66 Company
Keywords and Phrases
gas separation; hollow fiber; membrane; MOF; pressure; propylene
International Standard Serial Number (ISSN)
Article - Journal
© 2016 American Chemical Society (ACS), All rights reserved.