Next Article in Journal
A Study of Ralex Membrane Morphology by SEM
Next Article in Special Issue
The Role of Humic Acid, PP Beads, and pH with Water Backwashing in a Hybrid Water Treatment of Multichannel Alumina Microfiltration and PP Beads
Previous Article in Journal / Special Issue
Effect of Carbonic Anhydrase on CO2 Separation Performance of Thin Poly(amidoamine) Dendrimer/Poly(ethylene glycol) Hybrid Membranes
Open AccessArticle

Oil Deposition on Polymer Brush-Coated NF Membranes

1
Ralph E Martin Department of Chemical Engineering, University of Arkansas, Fayetteville, AR 72701, USA
2
Department of Civil & Environmental Engineering, Technion—Israel Institute of Technology, Haifa 32000, Israel
3
Department of Biomedical Engineering, University of Arkansas, Fayetteville, AR 72701, USA
*
Author to whom correspondence should be addressed.
Equal contributions.
Membranes 2019, 9(12), 168; https://doi.org/10.3390/membranes9120168
Received: 25 October 2019 / Revised: 17 November 2019 / Accepted: 29 November 2019 / Published: 6 December 2019
Membrane-based processes are attractive for treating oily wastewaters. However, membrane fouling due to the deposition of oil droplets on the membrane surface compromises performance. Here, real-time observation of the deposition of oil droplets by direct confocal microscopy was conducted. Experiments were conducted in dead-end and crossflow modes. Base NF 270 nanofiltration membranes as well as membranes modified by grafting poly(N-isopropylacrylamide) chains from the membrane surface using atom transfer radical polymerization were investigated. By using feed streams containing low and high NaCl concentrations, the grafted polymer chains could be induced to switch conformation from a hydrated to a dehydrated state, as the lower critical solution temperature for the grafted polymer chains moved above and below the room temperature, respectively. For the modified membrane, it was shown that switching conformation of the grafted polymer chains led to the partial release of adsorbed oil. The results also indicate that, unlike particles such as polystyrene beads, adsorption of oil droplets can lead to coalescence of the adsorbed oil droplets on the membrane surface. The results provide further evidence of the importance of membrane properties, feed solution characteristics, and operating mode and conditions on membrane fouling. View Full-Text
Keywords: direct observation; emulsion; responsive membrane; thermo-responsive polymer; surface modification; wastewater direct observation; emulsion; responsive membrane; thermo-responsive polymer; surface modification; wastewater
Show Figures

Figure 1

MDPI and ACS Style

Vu, A.; Mark, N.S.; Ramon, G.Z.; Qian, X.; Sengupta, A.; Wickramasinghe, S.R. Oil Deposition on Polymer Brush-Coated NF Membranes. Membranes 2019, 9, 168.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop