Uniformity control and ultra‐micropore development of tubular carbon membrane for light gas separation

Abstract

Tubular carbon molecular sieve (CMS) membranes have been recognized as a potential module for commercial application due to its high mechanical strength and large surface area. However, the carbon layer uniformity was restricted by substrate texture and dope fluidity when the dip-coating method was used. This study evaluated the influence of various parameters of dip-coating with an integrated vacuumassisted system, including solvent vaporization rates, vertical immersion/withdrawal velocity, vacuum degree, dope composition, coating cycles on the microstructure, and gas separation performance of CMS membranes. Using vacuum assistance and a low-vaporization solvent minimized the influence of viscosity and gravity on dope fluidity as a result of fast phase inversion. The as-prepared tubular CMS membranes showed enhanced perm-selectivity according to a H 2 /N 2 gas selectivity of 8.8, a CO 2 /N 2 gas selectivity of 6.7, a H 2 permeability of 464 barrer, and a CO 2 permeability of 356 barrer.

Advanced and sustainable manufacturing methods of polymer-based membranes for gas separation: a review

“…The method is effectively utilized in developing membranes for various gas separations like CO 2 /N 2 (Li et al, 2021), CO 2 /CH 4 (Suleman et al, 2018), H 2 (Farjoo and Kuznicki, 2016) and, O 2 /N 2 (Sazali et al, 2020). The optimum concentration of the casting solution and the temperature were identified as key factors in achieving a uniform membrane (Li et al, 2020). Research has demonstrated that parameters such as the concentration of the coating solution (Jamil et al, 2020), withdrawal speed, and the number of coatings applied (Shankar and Kandasamy, 2019) are vital in tuning the membrane's gas separation characteristics, highlighting the importance of process control in achieving the • High cost…”