Novel Perfluorooctanesulfonate-Imprinted Polymer Immobilized on Spent Coffee Grounds Biochar for Selective Removal of Perfluoroalkyl Acids in Synthetic Wastewater

Abstract

Wastewater is an important source of perfluoroalkyl acids (PFAAs) to environmental waters. PFAAs are poorly removed during conventional wastewater treatment and only moderately removed by nonselective adsorbents [e.g., activated carbon (AC)]. Molecularly imprinted polymers (MIPs) enable selective adsorption of trace organics (e.g., PFAAs) by templating polymerization with a target compound; however, MIP morphology limits use for wastewater treatment. To overcome this obstacle, a perfluorooctanesulfonate (PFOS)-templated MIP was immobilized on spent coffee grounds biochar�an eco-friendly AC alternative�via radical initiated polymerization. Vinylbenzyl trimethylammonium chloride (VBTAC) and/or 2-(trifluoromethyl)acrylic acid served as functional monomers for MIP synthesis. First, biochar surfaces were functionalized with −NH MIP attachment points via (i) electrophilic aromatic substitution followed by reduction or (ii) heat-catalyzed addition of melamine. Melamine-modified biochar functionalized with VBTAC-MIP

Simultaneous Oxidation of Trace Organics and Sorption of Trace Metals by Ferrate (Fe(VI))-Coated Sand in Synthetic Wastewater Effluent

“…Batch kinetics experiments were also conducted under synthetic wastewater (SWW) effluent conditions to characterize the effects of the wastewater effluent matrix on the Fe(VI)-coated sand treatment capacity for the select trace contaminants. The matrix was prepared based on wastewater effluent (real and synthetic) compositions reported in the literature. ,− The SWW composition included the following: NaHCO 3 (96 mg/L), NaCl (83 mg/L), MgCl 2 ·6H 2 O (19 mg/L), Mg(NO 3 ) 2 ·6H 2 O (10 mg/L), CaCl 2 ·2H 2 O (89 mg/L), Ca(NO 3 ) 2 ·4H 2 O (10 mg/L), and Na 2 HPO 4 (1 mg/L). The detailed composition of the synthetic matrix is included in Table S4.…”

A Critical Review on PFAS Removal from Water: Removal Mechanism and Future Challenges

“…To improve the adsorbent's selectivity for PFAS, a layer of molecularly imprinted polymers (MIP) was added onto the surface of the nitrogen-modified biochar using thermally stimulated radical-initiated polymerization. The BC-M-MIP exhibited higher Kselectivity for PFBS (4.52) and PFOA (3.76) compared to unmodified biochar at 0.043 and 0.039 mg PFAA/g*g/m 2 , respectively [66]. In another experiment, tree bark and eucalyptus biochar were used for the removal of different chain lengths of PFAS (4 to 11 fluorinated carbons).…”

An Overview on Recent Advances in Biomimetic Sensors for the Detection of Perfluoroalkyl Substances

“…In addition, it enhances both the availability of the target to the binding regions as well as the corresponding kinetics [ 118 ]. Polystyrene microspheres, silica nanoparticles, carbonaceous nanomaterials, and magnetic nanoparticles are examples of frequently employed carriers [ 119 , 120 , 121 , 122 ]. The surfaces of imprinted substances are controllable, and the recognition regions with high density are easily accessible by the targets, improving the adsorption capacity and effectiveness [ 118 , 123 , 124 ].…”