Effect of heat-press conditions on electrospun membranes for desalination by direct contact membrane distillation

• Electrospun membranes show good potential for membrane distillation. • Heat-press treatment can improve the properties of electrospun membrane. • Heat-press conditions are comprehensively studied here. • Heat-press temperature and duration play more important roles in heat-press.

0.21 Porosity (%) Feed solution Feed velocity (m s−1) fluffy internal structure of electrospun membrane into reasonably dense and uniform ones (Fig. 12c), and hence improve the mechanical properties and LEP greatly, resulting in impressively high salt rejection for long-term MD test. It was also interesting to point out that in previous studies, relatively low concentration of polymer was applied to obtain membranes with small pore size. However, heat-press treatment could further decrease the pore size and make it lower than optimal range for MD, resulting in low permeate flux. In conclusion, the present result addresses the importance and potential of heat-press on electrospun membrane for improved MD performance.