Study of the presence of PCDDs/PCDFs on zero-valent iron nanoparticles. (February 2017)

• Record Type: Journal Article
• Authors: Calderon, Blanca; Lundin, Lisa; Aracil, Ignacio; Fullana, Andres
• Is Part Of: Chemosphere. Volume 169(2017)
• Page Start: 361
• Page End: 368
• Publication Date: 2017-02
• Subjects: Toxicity -- PCDD/F -- Nanoparticles -- nZVI -- Iron chloride; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2016.11.074
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Studies show that nanoscale zero-valent iron (nZVI) particles enhance the formation of chlorinated compounds such as polychlorinated dioxins and furans (PCDD/Fs) during thermal processes. However, it is unclear whether nZVI acts as a catalyst for the formation of these compounds or contains impurities, such as PCDD/Fs, within its structure. We analyzed the presence of PCDD/Fs in nZVI particles synthesized through various production methods to elucidate this uncertainty. None of the 2, 3, 7, 8-substituted congeners were found in the commercially-produced nZVI, but they were present in the laboratory-synthesized nZVI produced through the borohydride method, particularly in particles synthesized from iron (III) chloride rather than from iron sulfate. Total PCDD/F WHO-TEQ concentrations of up to 35 pg/g were observed in nZVI particles, with hepta- and octa-chlorinated congeners being the most abundant. The reagents used in the borohydride method were also analyzed, and our findings suggest that FeCl3 effectively contains PCDD/Fs at concentrations that could explain the concentrations observed in the nZVI product. Both FeCl3 and nZVI showed a similar PCDD/F patterns with slight differences. These results suggest that PCDD/Fs might transfer from FeCl3 to nZVI during the production method, and thus, care should be taken when employing certain nZVI for environmental remediation. Graphical abstract: Highlights: This study analyzes the PCDD/Fs content in commercial and lab-synthesized-nZVI. PCDD/Fs are found in nZVI synthesized by the wet chemical reduction route. The origin of PCDD/Fs is ascribed to the iron chloride used for nZVI synthesis. Transport of PCDD/Fs from iron chloride to nZVI during synthesis is demonstrated.