Preparation and characterization of PSF/PEI/CaCO3 nanocomposite membranes for oil/water separation

Abstract

Ultrafiltration (UF) is one of the significant advanced processes for oily wastewater treatment due to its clear advantages, for instance, ease in operation and efficient separation. The main drawback of these processes is the fouling problem and many researchers' effort on fabrication of high-performance membranes with higher hydrophilicity and antifouling properties. In this study, flat-sheet polysulfone (PSF)/polyethylenimine (PEI)/CaCO nanocomposite membranes were prepared by phase inversion method for oil/water emulsion separation. Structural properties of membranes were characterized by SEM, FT-IR, contact angle, tensile strength, and atomic force microscopy analysis. Increasing the CaCO nanoparticle loading exhibited the increased the water flux and BSA rejection. PSF/PEI/10 wt% CaCO nanocomposite membranes have 145 L/m h water flux at 2 bar with a contact angle of 84° and with 92% BSA rejection. All prepared CaCO nanocomposite membranes reached similar oil rejections at above 90%. Besides the higher water flux and oil removal efficiencies, 10 wt% of CaCO nanoparticle-blended PSF membranes has notable antifouling capacity with the highest flux recovery ratio (FRR) and lowest flux decay ratio (DR) values. The results showed that there is a great potential to use PSF/PEI/CaCO nanocomposite membranes for the treatment of oil water emulsions with higher permeability and antifouling capacity.

Investigation of characteristic and performance of polyvinyl chloride ultrafiltration membranes modified with silica‐oriented multi walled carbon nanotubes

“…[38] The changes in the membranes surface pore size and porosity might be attributed to the stronger hydrophilic nature of Si-MWCNT nanoparticles and the high casting solution viscosity, which accelerated the exchange rate between solvent and nonsolvent during the phase inversion which, in turn, led to a higher membrane porosity and a larger porous structure. [39,40] These results are also in accordance with the porosity and pore size data listed in Table 2. However, excessive viscosity caused the pores of the blend membranes became irregular and the connections among layers became poor when further Si-MWCNT nanoparticles were added.…”

Investigation of the applicability of TiO2, BiVO4, and WO3 nanomaterials for advanced photocatalytic membranes used for oil‐in‐water emulsion separation

“…Therefore, the development of effective treatment methods of oily wastewaters is of great interest 15,16 . To comply with the stringent emission limits, conventional techniques—such as skimming, 17 sand filtration, 18 centrifugation, 19 flotation, 20 adsorption, 5 or chemical destabilization 21,22 —must be augmented with advanced method(s) such as membrane filtration, which can eliminate the usually remaining microsized and nanosized oil droplets 23–26 …”

Intensification of the ultrafiltration of real oil-contaminated (produced) water with pre-ozonation and/or with TiO2, TiO2/CNT nanomaterial-coated membrane surfaces

“…Zeta potential (mV) -19.1 ± 0.5 -26.3 ± 0.2 . Saki et al also published much lower achievable fluxes (in the case of a heavily oil-contaminated water) by using their PSF/PEI/CaCO 3 nanocomposite UF membranes: fluxes were 28, 26, 32, and 98 L m −2 h −1 for the membranes with 1, 2, 5, and 10 wt% CaCO 3 nanoparticle loadings, respectively, at 2 bar pressure (Saki and Uzal 2018). Our results confirm the significant advantages of the used highly hydrophilic nanomaterial coating in the case of real oily wastewaters (produced waters), as it inhibited the adherence of the oil droplets to the surface, preventing the formation of a hydrophobic water barrier layer and the fouling of the pores.…”

“…This enables the effective elimination of not just the floating and dispersed oil but the emulsified micro-and nano-sized oil droplets as well. As membrane filtration, microfiltration (Abadi et al 2011;Hu et al 2015;Masoudnia et al 2014;Salahi et al 2010;Shokrkar et al 2012;Zhang et al 2018), ultrafiltration (Masoudnia et al 2014;Saki and Uzal 2018;Salahi et al 2010;Yi et al 2011), nanofiltration (Golpour and Pakizeh 2017;Zhao et al 2019), or even reverse osmosis (Kasemset et al 2013) can be used, resulting in increasing purification efficiency in this order.…”

“…Membrane surface modificationvia the improvement of the hydrophilicityis another very effective method to reduce membrane fouling in the case of hydrophobic oily contaminants. There are various methods to improve the hydrophilicity of membranes (Miller et al 2017;Van der Bruggen 2009) including sulfonation (Baroña et al 2007), carboxylation (Sajitha et al 2002), polymer blending (Fang et al 2017), plasma-or UV-induced grafting (Susanto et al 2007;Wavhal and Fisher 2002;Wu et al 2018), and nanoparticlebased surface modifications (Hu et al 2015;Islam et al 2017;Saki and Uzal 2018;Yi et al 2011;Yin and Zhou 2015;Zhou et al 2010). Among the various nanomaterials, the ones with photocatalytic properties can provideapart from the increased hydrophilicitythe possibility to degrade organic fouling contaminants by simple UVor solar irradiation, which proved to be efficient to decompose oily contaminants from membrane surfaces (Chang et al 2014;Gondal et al 2014;Moslehyani et al 2015;Pan et al 2012;Shi et al 2016;Tan et al 2015).…”