Fabrication of ordered mesoporous carbon hollow fiber membranes via a confined soft templating approach

Abstract

Ordered mesoporous carbon (OMC) membranes have broad applications such as size exclusion separation of molecules. In this work, a new method to prepare OMC hollow fiber membranes through a confined soft templating route is developed. In this method, commercialized polymeric hollow fiber ultrafiltration membranes were immersed in an ethanol solution containing a phenolic resin and a Pluronic triblock copolymer. Upon solvent evaporation, the phenolic resin and the surfactant self-assembled into the confined voids of the ultrafiltration membrane. After drying and pyrolysis, OMC hollow fiber membranes were obtained. The OMC hollow fiber membranes possess continuous membrane walls with an average thickness of 113 μm. The membrane wall has a hierarchical pore structure: one coming from hexagonally ordered mesoporous carbon with a pore diameter of ∼4.3 nm and the other being disordered defect holes with a size of 8–50 nm randomly distributed inside the OMC matrix. The gas permeance results indicate that the OMC hollow fiber membranes exhibit Knudsen diffusion behavior confirming their good quality.