Health & Environmental Research Online (HERO)


Print Feedback Export to File
6315690 
Journal Article 
Application of zero-valent iron coupled with biochar for removal of perfluoroalkyl carboxylic and sulfonic acids from water under ambient environmental conditions 
Liu, Y; Ptacek, CJ; Baldwin, RJ; Cooper, JM; Blowes, DW 
2020 
Yes 
Science of the Total Environment
ISSN: 0048-9697
EISSN: 1879-1026 
719 
137372 
English 
Advanced oxidation and reduction processes have been intensively investigated as potential methods to promote the decomposition of perfluoroalkyl substances (PFASs). However, extreme operational conditions such as highly acidic pH, high temperature, and high pressure are required to promote degradation reactions, which makes these technologies costly and less feasible for full-scale applications. The objective of this study was to evaluate the effectiveness of zero-valent iron (ZVI) alone and a mixture of ZVI and biochar (ZVI + BC) for removal of seven target PFASs from water under ambient environmental conditions. Target PFASs included three perfluoroalkyl carboxylic acids (PFCAs) [perfluorooctanoic acid (PFOA, C8-PFCA), perfluoroheptanoic acid (C7-PFCA), and perfluorohexanoic acid (C6-PFCA)] and four perfluoroalkyl sulfonic acids (PFSAs) [perfluorooctane sulfonic acid (PFOS, C8-PFSA), perfluoroheptane sulfonic acid (C7-PFSA), perfluorohexane sulfonic acid (C6-PFSA), and perfluorobutane sulfonic acid (C4-PFSA)]. Batch test results show that PFSAs (up to 94% removal) were more effectively removed than PFCAs (up to 60% removal) when utilizing either ZVI or (ZVI + BC). About 20-60% of input PFOA (~18,550 μg L-1) and 90-94% of input PFOS (~18,580 μg L-1) were removed by ZVI alone or the mixture of (ZVI + BC). The removal efficiencies of PFCAs and PFSAs by reactive media increased with increasing chain length, from 0 to 17% for short-chain PFCAs (C6-C7) and 20 to 70% for short-chain PFSAs (C4-C7). About 5-10% of input PFOA and PFOS was partially defluorinated by ZVI alone as indicated by F- release; however, the defluorination efficiency may be underestimated due to the sorption of F- by the reactive media. Overall, the reactive mixture (ZVI + BC) may be an effective and environmentally sustainable material for removing PFASs from water under ambient environmental conditions. 
Removal; Perfluoroalkyl carboxylic acids; Perfluoroalkyl sulfonic acids; Zero-valent iron; Biochar 
• PFBS
     LitSearch: May 2019 - May 2020
          WoS
          PubMed
• PFHxA
     LitSearch: May 2019 - May 2020
          PubMed
          WoS
• PFHxS
     LitSearch: May 2019 - May 2020
          PubMed
          WoS
• PFOA (335-67-1) and PFOS (1763-23-1)
     LitSearch: Feb 2019 - May 2020
          WoS
          PubMed
     Literature Search Update (Apr 2019 - Sep 2020)
          PubMed
          WOS