Hyperbranched Polyethyleneimine Induced Cross-Linking of Polyamide−imide Nanofiltration Hollow Fiber Membranes for Effective Removal of Ciprofloxacin

Abstract

This study aims to develop a positively charged nanofiltration (NF) hollow fiber membrane for effective removal of ciprofloxacin from water. A novel NF membrane was fabricated by hyperbranched polyethyleneimine (PEI) induced cross-linking on a polyamide-imide hollow fiber support. The spongy-like, fully porous membrane support provides minimal transport resistance and sufficient mechanical strengths for water permeation under high pressures. It is found that the PEI modification significantly influences NF performance through the mechanisms of size exclusion, charge repulsion, and solute-membrane affinity. Specifically, after PEI induced cross-linking, the membrane pore size is significantly reduced. The membrane surface becomes more hydrophilic and positively charged. As a result of these synergic effects, the rejection of ciprofloxacin is substantially enhanced. Furthermore, experimental results show that the molecular weight of PEI has tremendous effect on NF performance of the as-modified membrane. The NF membrane modified by a high molecular weight PEI_60K exhibits the highest rejection, the lowest fouling tendency, and keeps a constant flux over the whole pH range. This study may have great potential for developing high-performance antifouling NF hollow fiber membranes for various industrial applications.

Investigation of ciprofloxacin removal from aqueous solution by nanofiltration process

“…In addition, solutes can be rejected on NF membrane by one or a combination of three basic mechanisms including size exclusion (sieve steric effect), charge exclusion (electrical, Donnan), and physico-chemical interactions between solute, solvent and membrane (Yoon et al, 2006;Acero et al, 2010;Dolar et al, 2011;Sun et al, 2011;Vergili, 2013). Moreover it is also reported in the literature that size exclusion in tight membranes and charge exclusion and physicochemical interaction in the other membranes were more effective mechanisms in membrane filtration (Dolar et al, 2011).…”

“…CIPRO was found in wastewater treatment plant effluents at concentrations of 313-568 ng l -1 and up to 124.5 µg l -1 in hospital sewage water (De Witte et al, 2009). Although, the presence of trace levels (ng l -1 ) of CIPRO in wastewater effluents, receiving waters and drinking water sources led to negative impacts on ecological and human health (Comerton et al, 2008;Vasconcelos et al, 2009;Wu et al, 2013), effective removal of this compound from discharge streams to the environment becomes an important issue (Sun et al, 2011).…”

“…A number of promising wastewater treatment technologies have been used for removing CIPRO from wastewater, such as sorption and adsorption (Wu et al, 2010;Jiang et al, 2013a;Rakshit et al, 2013;Genç et al, 2013;Wu et al, 2013), membrane separation (Sun et al, 2011;Zaviska et al, 2013;Urtiaga et al, 2013), ozonation, oxidation and other photocatalytic degradation processes (De Witte et al, 2009;Vasconcelos et al, 2009;De Witte et al, 2010;Jiang et al, 2012;Jiang et al, 2013b;Zhou and Jiang, 2015). Notwithstanding the differences between degradation mechanisms of these oxidation processes, the byproducts formed may be the same, or at least, similar to each other (Vasconcelos et al, 2009).…”

Green modification of outer selective P84 nanofiltration (NF) hollow fiber membranes for cadmium removal

“…Hyperbranched PEI (MW: 60K gmol -1 ) was employed to enhance the rejection and bring in more amine groups onto the surface of the P84 substrate [43,44]. Small molecules such as TMC, glutaraldehyde (GA) and epichlorohydrin (ECH), with molecular structures shown in Figure 1, were used to further cross-link the unreacted amine groups on the membrane surface after the PEI cross-linking.…”

Response surface methodological approach for optimizing removal of ciprofloxacin from aqueous solution using thermally activated persulfate/aeration systems

“…Ciprofloxacin carried into the environment via disposals of sewage treatment plants, leaching from landfills, pharmaceutical industries, livestock activities and application of sewage sludge (Topp et al, 2008;Bobu et al, 2008). A number of promising waste water treatment methods have been used to remove CIP from aqueous solution, such as membrane separation (Avella et al, 2010), Ozonation (De Witte et al, 2010), Naofiltration (Sun et al, 2011), Photocatalytic Degradation (Van Doorslaer et al, 2011), Adsorption (Carabineiro et al, 2012) and Advanced Oxidation Process (Ji et al, 2014). Among these, Advanced Oxidation Processes (AOPs) are considered as an effective method to remove non-biodegradable organic pollutants such as CIP from aqueous solution (Bobu et al, 2008).…”