Removal of aqueous perfluorooctanoic acid (PFOA) using starch-stabilized magnetite nanoparticles

Yanyan Gong; Lin Wang; Juncheng Liu; Jingchun Tang; Dongye Zhao

doi:10.1016/j.scitotenv.2016.03.100

Removal of aqueous perfluorooctanoic acid (PFOA) using starch-stabilized magnetite nanoparticles

Sci Total Environ. 2016 Aug 15:562:191-200. doi: 10.1016/j.scitotenv.2016.03.100. Epub 2016 Apr 18.

Authors

Yanyan Gong¹, Lin Wang², Juncheng Liu², Jingchun Tang³, Dongye Zhao⁴

Affiliations

¹ College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin 300350, China; Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China.
² College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
³ College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin 300350, China; Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, Tianjin 300350, China. Electronic address: tangjch@nankai.edu.cn.
⁴ Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA. Electronic address: zhaodon@auburn.edu.

PMID: 27100000
DOI: 10.1016/j.scitotenv.2016.03.100

Abstract

Fully stabilized magnetite (Fe3O4) nanoparticles were prepared with a water-soluble starch as a stabilizer and tested for removal of aqueous perfluorooctanoic acid (PFOA). The presence of starch at ≥0.2wt% can fully stabilize 0.1g/L as Fe of the Fe3O4 nanoparticles. The particle stabilization technique resulted in 2.4 times higher PFOA uptake. Fourier transform infrared spectra suggested that the main PFOA removal mechanism was inner-sphere complexation. Batch kinetic experiments revealed that the starch-stabilized nanoparticles facilitated a rapid PFOA uptake with a sorption equilibrium time of 30min, and the sorption process followed a pseudo-second-order kinetic model. The Langmuir model was able to well interpret the adsorption isotherm, with a maximum adsorption capacity of 62.5mg/g. Increasing pH from 4.7 to 9.6 led to a sharp increase (by 2.6 times) in PFOA uptake. The presence of 12mg/L humic acid inhibited PFOA uptake by 96%, while effect of ionic strength (CaCl2=0-2mmol/L) was negligible. The nanoparticles significantly reduced the biological toxicity of PFOA. The results demonstrated promise of starch-stabilized Fe3O4 nanoparticles as a "green" adsorbent for effective removal of PFOA in soil and groundwater.

Keywords: Adsorption; Emerging contaminants; Groundwater remediation; Magnetite nanoparticles; Perfluorooctanoic acid.

Publication types

Research Support, Non-U.S. Gov't