18 mω barnstead smart2pure system

Methanol, vinyl imidazole, allyl bromide, Poly N-(3-sulfopropyl)-N-(methacryloxyethyl)-N,N-dimethylammonium betaine (SAMB), potassium permanganate (KMnO₄), and sodium hydroxide (NaOH) were purchased from Sigma Aldrich (St. Louis, MO, USA). Benzophenone was purchased from (Acros Organics, Morris, NJ, USA) while ethyl acetate was purchased from Alfa-Aesar (Ward Hill, MA, USA). Nitric acid (HNO₃) was procured from VWR (Radnor, PA, USA). Deionized (DI) water was obtained from a Thermo Fisher 18 MΩ (Barnstead Smart2Pure system, Schwerte, Germany). Polyvinylidene fluoride (PVDF) membranes were provided by Millipore Sigma (Billerica, MA, USA).

All reagents were ACS grade or higher, unless specified. Methanol, glycerol and acetonitrile were purchased from MilliporeSigma (Billerica, MA, USA). Triethylamine (TEA); 4-dimethylaminopyridine (DMAP); N,N,N′,N″,N″-pentamethyl diethylenetriamine (PMDETA, 99%); sodium phosphate monobasic (99%); sodium phosphate dibasic (99%) copper (I) chloride; copper (II) chloride and copper(I) bromide (CuCl, CuCl₂ and CuBr 99.999% trace metal basis) were purchased from Sigma-Aldrich (Munich, Germany). α-Bromoisobutyryl bromide (BIB, 98%) was purchased from Alfa-Aesar (Ward Hill, MA, USA). 1,2-epoxy-5-hexene and 2-hydroxyethylmethacrylate (HEMA, >97%, stabilized) was purchased from Acros Organic (98%, Pittsburgh, PA, USA). Bovine serum albumin (BSA, biotechnology grade) and L-(+)-ascorbic acid (AA) were purchased from Amresco (Solon, OH, USA). 2,2′-Bipyridine (Bpy) was purchased from BeanTown Chemical (Hudson, NH, USA). Iron oxide superparamagnetic nanoparticles with a 15-nm core diameter and a 5-nm coating layer functionalized with amine groups were purchased from Ocean Nanotech (San Diego, CA, USA). All water used in this work was obtained from a Thermo Fisher 18 MΩ Barnstead Smart2Pure System (Schwerte, Germany). Commercially available regenerated cellulose membranes with a nominal molecular weight cutoff of 100 kDa were purchased from MilliporeSigma (product codes: PLCHK and PCLMK).

ECTFE base membrane with 0.1 μm nominal pore size, 0.69 porosity and 91 μm thickness; was procured from MilliporeSigma (Billerica, MA, USA). Potassium permanganate (KMnO₄) and nitric acid (HNO₃) were procured from VWR, Radnor, PA, USA. Deionized water was used throughout the investigation was collected from Thermo Fisher 18 MΩ Barnstead Smart2Pure system, Schwerte, Germany. The produced water (PW) was collected from Southwestern Energy sites, Virginia after hydraulic fracturing and prefiltration. This collected PW was used throughout the investigation without any further pretreatment. Table 1 summarizes the characterization of PW.