Preparation of High Performance Hollow Fiber Membranes for CO2 Capture

Abstract

Preparation of polybezoxazole (PBO) asymmetric membranes and PBO hollow fiber membranes were studied by introducing additives into the solutions. The additives were used to include ethylene glycol, a mixture of ethylene glycol/tetrahydofuran (THF), and LiCl as an inorganic salt. N-methyl-2-pyrrolidone (NMP) was used as a solvent. PBO hollow fiber membranes were spun using water as an external coagulant and an internal coagulant. The solution composition with various ratio of additives, effect of air gap, and thermal rearrangement conditions on membrane morphology and separation properties were investigated. The amount and type of additives, air gap distance, and thermal rearrange condition affect the hollow fiber membrane morphology and separation properties. PBO hollow fiber membranes with high CO2 permeability can be prepared using various factors such as the solution composition, the length of the air gap, and thermal rearrangement conditions.