Functionalized Activated Carbon Fibers by Hydrogen Peroxide and Polydopamine for Efficient Trace Lead Removal from Drinking Water

Abstract

To achieve efficient and selective trace heavy metals removal from drinking water, a low-cost purification material polydopamine/activated carbon fibers (PDA/H-ACF) was successfully prepared by polymerizing dopamine on the surface of activated carbon fibers pretreated with hydrogen peroxide. The morphology, phase, surface functional groups, specific surface, and pore size distribution of the as-prepared sample were analyzed using FESEM, XPS, BET and pore size distribution test (PST), and FTIR, and orthogonal experiments were used to investigate the influences of concentration of H 2 O 2 , pretreatment time, and reflux temperature on trace lead removal. The results showed that the sample pretreated under optimized conditions could produce different pore structures, and the content of functional group −COOH obviously increased. After further modification by polydopamine, the contents of −NH−, −NH 2 , and −OH functional groups on the surface obviously enhanced, which were beneficial to increase adsorption site and promote trace lead removal. The effluent lead concentration decreased from initial 150 to 3.18 ppb within 5 min, meeting the requirement of NSF International Standard/American National Standard for Drinking Water Treatment Units (NSF/ANSI 53−2020) (5 ppb). The isothermal adsorption process and adsorption kinetics could be well-fitted by the Langmuir isotherm and pseudo-second-order kinetics model, indicating that the adsorption process of trace lead by PDA/H-ACF belonged to monolayer and chemical adsorption. Moreover, the as-prepared PDA/H-ACF also showed superior trace lead adsorption performance in the presence of high concentration competitive metal ions, in a wide pH range and in tap water, and therefore had good application prospect in the field of drinking water purification.

Polyhedral Oligomeric Silsesquioxane Encountering Tannic Acid: A Mild and Efficient Strategy for Interface Modification on Carbon Fiber Composites

“…The peak fitting of C 1s and N 1s regions’ deconvolution spectra is used to evaluate the detailed chemical bonds of the fiber surface (displayed in Figure b–e, Table S2 and Figure S2). For the C 1s spectra, the original three peaks are assigned to C–C (284.6 eV), C–N (285.7 eV), and C–O (286 eV) of the de-sized CF. ,,, After co-deposition of TA/POSS on the fiber surface, four new peaks are observed, which can be assigned to C–Si (284.2 eV), CN (287 eV), CO (288.1 eV), and O–CO (289 eV). ,,,, …”

Highly Efficient and Simultaneous Removal of Cr(VI) and Imidacloprid through a Ferrocene-Modified MIL-100(Fe) Composite from an Aqueous Solution

“…In particular, nanoporous materials, polymers, and green materials had been developed for adsorbing and removing pollutants in the environment . For example, Zuo et al studied hydrogen peroxide and polydopamine functions to activate carbon fiber to adsorb lead ions in water . Mondal et al studied the chitosan biopolymer as an adsorbent to remove Pb­(II) and Zn­(II) .…”

Improve the Interfacial Properties between Poly(arylene sulfide sulfone) and Carbon Fiber by Double Polymeric Grafted Layers Designed on a Carbon Fiber Surface

“…Because of its excellent adhesive property, convenience, wide application system, wonderful environmental protection, and no deterioration of properties of carbon fiber (Figure S1 in the Supporting Information), PDA has become the most popular and potential modification material in the interphase and nanomaterial modification. − Moreover, after self-polymerization of dopamine (DA) on CF surface (Figure ), the PDA can build reliable adhesion with carbon fiber by chemical and physical bonds, giving carbon fiber a lot of chemical reaction sites, such as hydroxyl, amino, carbonyl, which are beneficial to the next modification of carbon fiber. Nonetheless, just PDA, which has a bountiful cross-connected and fragrant design, is excessively inflexible to cause a pressure focus at the interphase .…”