Effect of non‐solvent on the synthesis of polyvinylidene fluoride membranes for vacuum membrane distillation desalination

Abstract

The need for freshwater boosted the research for alternative technologies with a cleaner and more efficient approach. Membrane distillation (MD) stands out due to its efficiency in purifying aqueous solutions and easy operation. Thus, this work aims at developing and characterizing polyvinylidene fluoride membranes using the non-solvent phase inversion (NIPS) methodology for the MD process. Distilled water and ethanol (at different proportions) were tested as non-solvent and N'N'dimethylformamide as solvent. The morphology, crystallinity, and porosity of each sample were determined. The utilization of ethanol as non-solvent produced more hydrophobic membranes with higher liquid entry pressure. Scanning electron microscope analysis showed that different proportions of water and ethanol changes the morphology of the resulting membrane, with clear influence on the formation of macrovoids. The samples crystallinity was over 54% and the porosity, over 55%. The sample with best results in the vacuum MD process prpesented an average of over 98% of salt retention during a period of 6 h. This work shows the beneficial influence ethanol as non-solvents for the preparation of PVDF membranes for the process of hydrophobic vacuum MD.

Synthesis and characterization of tubular ceramic ultrafiltration membrane from coal fly ash

“…Membrane separation is an advanced green and eco‐friendly technique gaining more attention in the recent years due to its unique advantages such as low energy consumption, high efficiency, cost‐effectiveness and scaleup to industries (Bazin et al., 2019; Fu et al., 2019; Mouiya et al., 2019). Polymeric, glass, ceramic, and metal membranes are the existing commercial membranes for various commercial and industrial applications (Bakhtiari et al., 2011; Emani et al., 2013; Hubadillah et al., 2016; Sachett et al., 2022). Nowadays, ceramic membranes are gaining the attention of many researchers and industrialists across the world due to their attractive properties such as high mechanical, chemical, and thermal stability, long life span, ease of cleaning, anti‐fouling property and durability.…”