A simple one-step drop-coating approach on fabrication of supported carbon molecular sieve membranes with high gas separation performance

摘要

Supported carbon molecular sieve membranes (CMSMs) were fabricated from polyimide, via coating, drying, and pyrolysis. Thermogravimetric analysis, X-ray diffraction, and scanning electron microscope were used to characterize the thermal stability of precursor, microstructure, and morphology of CMSMs, respectively. The influences of coating droplets, pyrolysis temperature, permeation temperature, and pressure on the gas permeation of CMSMs were investigated. Results show that high-performance CMSMs can be easily obtained by one-step drop-coating. Coating with more droplets brings about more amorphous microstructure and higher gas permeability of CMSMs. The gas permeability of CMSMs increases with elevating permeation temperature or reducing pyrolysis temperature. The as-prepared CMSMs can enrich the molar composition of oxygen to 66% from the compressed air by single one time.