Abstract
Superhydrophobic poly(vinylidene fluoride) (PVDF) membrane incorporated with nanoparticles was applied in membrane distillation to recover water from phenolic rich solution containing surfactant. The membranes coated on woven support were fabricated using phase inversion with dual bath coagulation and post-modified using silane. The membranes incorporated with TiO2, SiO2, or a mixture of TiO2-SiO2 nanoparticles achieved the water contact angle higher than 160 degrees. The addition of TiO2-SiO2 mixture into PVDF matrix further enhanced the hierarchical roughness of membrane. Hence, PVDF/TiO2-SiO2 membrane achieved the highest permeation flux and rejected 99.9% of gallic acid in the feed (100 g/L). PVDF/TiO2-SiO2 membrane also maintained a relative flux (J/J(0)) higher than 0.9 after 8 h of operation. Even with the presence of surfactant in phenolic rich solution, PVDF/TiO2-SiO2 membrane was able to exhibit relative flux above 0.8. The significant changes on the hydrophobicity and chemical properties of PVDF/TiO2-SiO2 membrane due to fouling were not observed after 50 h of static adsorption test.