Optimizing membrane degassing with Hyflon AD 40L modified polypropylene hollow fiber and pre-filling techniques

This paper conducts a comparative analysis of the anti-wetting properties and degassing performance of both homemade and commercial membranes. Additionally, it introduces a unique approach for hydrophobic modification of high-flux membranes. The study involved the utilization of Hyflon AD40L for multiple coatings on the surface of polypropylene (PP) hollow fiber membranes. Several variables, including modification solution concentration, temperature, coating duration, number of coating cycles, polymer type, and the choice and concentration of the pore-blocking agent, were systematically investigated to establish the optimal modification process. Characterization of the modified membrane and degassing experiments revealed significant improvements. Specifically, the contact angle increased from 95.5° to 113.1°, while the trans-membrane differential pressure surged from 10.7 kPa to 154.6 kPa, marking a remarkable 14.4-fold enhancement. This enhancement is attributed to the improved anti-wetting capabilities of the modified membrane. In the degassing experiments, the modified membrane-based module demonstrated an impressive 95.0% dissolved oxygen removal rate, with a corresponding mass transfer coefficient reaching 18.01×10–3m·h–1. These results underscore the substantial potential of the Hyflon AD40L/PP membrane for applications in membrane degassing.