Novel Triple-Layer HIPS/SBR/PP Nanofibrous Membranes for Robust DCMD Desalination

In this work, a novel method for the fabrication of robust triple-layer membranes composed of nanofibrous high-impact polystyrene (HIPS) as the top layer, commercial fibrous polypropylene (C-PP) as a support layer, and styrene-butadiene rubber (SBR) fibers as a practical binder is proposed. After introducing the nanofibrous HIPS layer on the PP support layer, surface hydrophobicity was noticeably enhanced and the water contact angle was increased from 145.7 to 154.4 degrees. Also, the liquid entry pressure (LEP) and tensile strength were enhanced by 56.9 and 27.3%, respectively, compared to those of the C-PP membrane. The peeling test result confirmed sufficient adhesion between the layers of the fabricated membrane (5.4 +/- 0.6 N). Direct contact membrane distillation (DCMD) performance was assessed using two salty (35 and 100 g/L NaCl) feed solutions. A permeate flux of 18.33 kg/(m(2)h) was obtained for the triple-layer membrane for 100 g/L feed concentration, which is a good result for this membrane. The fabricated membrane demonstrated excellent salt rejection owing to its high LEP value and surface superhydrophobicity. Considering these achievements, HIPS/SBR/PP fibrous membranes could be a decent alternative for the DCMD desalination process.

Automated summary

A novel method for fabricating triple-layer membranes has been proposed, showing enhanced surface hydrophobicity, improved liquid entry pressure and tensile strength. The membranes exhibited excellent salt rejection and permeate flux, making them a promising option for desalination processes using direct contact membrane distillation (DCMD).