Janus Distillation Membrane via Mussel-Inspired Inkjet Printing Modification for Anti-Oil Fouling Membrane Distillation

In this work, inkjet printing technology was used to print a thin layer of a hydrophilic solution containing polydopamine as a binder and polyethyleneimine as a strong hydrophilic agent on a commercial hydrophobic membrane to produce a Janus membrane for membrane distillation. The pristine and modified membranes were tested in a direct-contact membrane distillation system with mineral oil-containing feedwater. The results revealed that an integrated and homogenous hydrophilic layer was printed on the membrane with small intrusions in the pores. The membrane, which contained three layers of inkjet-printed hydrophilic layers, showed a high underwater oil contact angle and a low in-air water contact angle. One-layer inkjet printing was not robust enough, but the triple-layer coated modified membrane maintained its anti-oil fouling performance even for a feed solution containing 70 g/L NaCl and 0.01 v/v% mineral oil concentration with a flux of around 20 L/m(2)h. This study implies the high potential of the inkjet printing technique as a facile surface modification strategy to improve membrane performance.

Automated summary

In this study, inkjet printing technology was used to print a hydrophilic solution on a commercial hydrophobic membrane for membrane distillation. The printed membrane showed a uniform hydrophilic layer with small intrusions in the pores. A triple-layer coated modified membrane exhibited excellent anti-oil fouling performance, even for a feed solution with high salt and mineral oil concentration. This research demonstrates the high potential of inkjet printing as a facile surface modification method to enhance membrane performance.