Journal article
Synthesis, Optimization, and Performance Demonstration of Electrospun Carbon Nanofiber–Carbon Nanotube Composite Sorbents for Point-of-Use Water Treatment
ACS applied materials & interfaces, Vol.8(18), pp.11431-11440
05/11/2016
DOI: 10.1021/acsami.6b01253
PMID: 27093306
Abstract
We developed an electrospun carbon nanofiber–carbon nanotube (CNF–CNT) composite with optimal sorption capacity and material strength for point-of-use (POU) water treatment. Synthesis variables including integration of multiwalled carbon nanotubes (CNTs) and macroporosity (via sublimation of phthalic acid), relative humidity (20 and 40%), and stabilization temperature (250 and 280 °C) were used to control nanofiber diameter and surface area (from electron microscopy and BET isotherms, respectively), surface composition (from XPS), and strength (from AFM nanoindentation and tensile strength tests). Composites were then evaluated using kinetic, isotherm, and pH-edge sorption experiments with sulfamethoxazole (log K ow = 0.89) and atrazine (log K ow = 2.61), representative micropollutants chosen for their different polarities. Although CNFs alone were poor sorbents, integration of CNTs and macroporosity achieved uptake comparable to granular activated carbon. Through reactivity comparisons with CNT dispersions, we propose that increasing macroporosity exposes the embedded CNTs, thereby enabling their role as the primary sorbent in nanofiber composites. Because the highest capacity sorbents lacked sufficient strength, our optimal formulation (polyacrylonitrile 8 wt %, CNT 2 wt %, phthalic acid 2.4 wt %; 40% relative humidity; 280 °C stabilization) represents a compromise between strength and performance. This optimized sorbent was tested with a mixture of ten organic micropollutants at environmentally relevant concentrations in a gravity-fed, flow-through filtration system, where removal trends suggest that both hydrophobic and specific binding interactions contribute to micropollutant uptake. Collectively, this work highlights the promise of CNF–CNT filters (e.g., mechanical strength, ability to harness CNT sorption capacity), while also prioritizing areas for future research and development (e.g., improved removal of highly polar micropollutants, sensitivity to interfering cosolutes).
Details
- Title: Subtitle
- Synthesis, Optimization, and Performance Demonstration of Electrospun Carbon Nanofiber–Carbon Nanotube Composite Sorbents for Point-of-Use Water Treatment
- Creators
- Katherine T PeterJohn D VargoThilini P RupasingheAribet De JesusAlexei V TivanskiEdward A SanderNosang V MyungDavid M Cwiertny
- Resource Type
- Journal article
- Publication Details
- ACS applied materials & interfaces, Vol.8(18), pp.11431-11440
- DOI
- 10.1021/acsami.6b01253
- PMID
- 27093306
- NLM abbreviation
- ACS Appl Mater Interfaces
- ISSN
- 1944-8244
- eISSN
- 1944-8252
- Publisher
- American Chemical Society
- Grant note
- DOI: 10.13039/100000139, name: U.S. Environmental Protection Agency, award: R835177; DOI: 10.13039/100000001, name: National Science Foundation
- Language
- English
- Date published
- 05/11/2016
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Center for Health Effects of Environmental Contamination; Civil and Environmental Engineering; Occupational and Environmental Health; Orthopedics and Rehabilitation; Craniofacial Anomalies Research Center; Public Policy Center (Archive); Chemistry; Chemical and Biochemical Engineering
- Record Identifier
- 9983985837502771
Metrics
16 Record Views