(267d) Free Surface Electrospun Polyvinylidene Fluoride Membranes for Direct Contact Membrane Distillation

Direct Contact Membrane Distillation (DCMD) can be utilized as a desalination process similar to traditional distillation and reverse osmosis. In DCMD a porous, hydrophobic membrane is used to desalinate water by separating nonvolatile molecules such as salt, and other impurities from seawater/brackish water. However, the DCMD process employs a temperature gradient to create a vapor pressure gradient; driving the separations of chemical species. Here, free surface electrospinning was considered to produce membranes for the DCMD process in large quantities while maintaining high porosity and controllability over pore size. A solution of Polyvinylidene Fluoride (PVdF) in Dimethylacetamide (DMac) was electrospun over a range of high voltages and times to produces varying fiber morphologies and membrane thicknesses. The membrane’s morphology was examined by scanning electron microscopy. In order to investigate the mechanisms responsible for efficient productivity, a DCMD setup was assembled. Various temperature gradients and flow rates were investigated with the DCMD setup. It was determined that increased temperature gradients and flow rates led to an increase in productivity. These observations suggest that higher temperature gradients provide a higher driving force for transport. This study aims to find a membrane’s maximum productivity by varying operational parameters.