Nanodiamond immobilized membranes for enhanced desalination via membrane distillation

Recent years have witnessed the emergence of detonation nanodiamonds (DNDs) as a new member of the nanocarbon family. This paper reports the immobilization of DNDs within a hydrophobic membrane for desalination applications. A dispersion of DNDs in polyvinylidene fluoride polymer was injected through a hydrophobic membrane, which incorporated the DNDs within the membrane. Embedding only a minimal quantity of (approximately 2%) the nanocarbon favorably altered the water vapor-membrane interactions to enhance water vapor permeability while preventing liquid penetration into the membrane pores thereby enhancing water vapor flux. Overall, desalination was consistently better with DND immobilized membrane than with conventional polypropylene, with flux enhancement as high as 118% in the sweep gas membrane distillation mode.