@article {84,
	title = {Sono-chemical treatment of per- and poly-fluoroalkyl compounds in aqueous film-forming foams by use of a large-scale multi-transducer dual-frequency based acoustic reactor.},
	journal = {Ultrason Sonochem},
	volume = {45},
	year = {2018},
	month = {2018 Jul},
	pages = {213-222},
	abstract = {<p>Aqueous film-forming foams (AFFFs) contain a mixture of organic chemicals, including per- and poly-fluorinated, alkyl sulfonate substances (PFAS) (1-5\%, w/w). Some longer-chain PFAS can be toxic, moderately bioaccumulative and persistent in the environment. In the present work, decomposition of PFAS present in two commercially available AFFFs (ANSUL- and 3M-) was investigated using a sono-chemical reactor of volume 91 L. The reactor consists of 12 transducers with operating frequencies of 1 MHz or 500 kHz and total input power of 12 kW. Degradation of PFASs performed using various dilutions of AFFF revealed that release of F and SO ions was inversely proportional to initial pH of up to 4. Defluorination of ANSUL-AFFF resulted in an increase in the concentration of F released from 55.6 {\textpm} 0.3 {\textmu}M (500{\texttimes} dilution) to 58.6 {\textpm} 0.6 (25{\texttimes} dilution), while for 3M AFFF it increased from 19.9 {\textpm} 0.7 {\textmu}M (500{\texttimes} dilution) to 217.1 {\textpm} 2.4 {\textmu}M (25{\texttimes} dilution). Though amounts of F released were less for ANSUL-AFFF than for 3M-AFFF, there was a considerable increase in removal of TOC and release of SO present in ANSUL-AFFF. Approximately 90.5\% and 26.6\% reduction of perfluoroalkyl sulfonates (PFSA) and perfluoroalkyl carboxylates (PFCA) in 3M, respectively, and 38.4\% reduction of fluorotelomer sulfonates in ANSUL-AFFF were achieved in 13 h. Estimated costs of energy for the treatment of ANSUL-AFFF and 3M-AFFF at a 500{\texttimes} dilution were $0.015 {\textpm} 0.0001/L and $0.019 {\textpm} 0.0002/L, respectively.</p>},
	issn = {1873-2828},
	doi = {10.1016/j.ultsonch.2018.02.014},
	author = {Gole, Vitthal L and Sierra-Alvarez, Reyes and Peng, Hui and Giesy, John P and Deymier, Pierre and Keswani, Manish}
}
@article {96,
	title = {Sonochemical degradation of perfluorinated chemicals in aqueous film-forming foams.},
	journal = {J Hazard Mater},
	volume = {317},
	year = {2016},
	month = {2016 Nov 05},
	pages = {275-283},
	abstract = {<p>Aqueous film-forming foams (AFFFs) are complex mixtures containing 1-5\% w/w fluorocarbons (FCs). Here, we have investigated degradation of two commercial AFFF formulations, 3M and Ansul, using sound field at 500kHz and 1MHz, with varying initial concentrations ranging from 200 to 930{\texttimes} dilution. The foams were readily degraded by 1MHz, with percentage of defluorination ranging from 11.1{\textpm}1.4\% (200{\texttimes} dilution of 3M) to 47.1{\textpm}5.8\% (500{\texttimes} dilution of Ansul). Removal of total organic carbon (TOC) ranged from 16.0{\textpm}1.4\% (200{\texttimes} dilution Ansul) to 39.0{\textpm}7.2\% (500{\texttimes} dilution Ansul). Degradation of AFFF was affected by sound frequency with rates of defluorination 10-fold greater when the frequency was 1MHz than when it was 500kHz. Mineralization of TOC was 1.5- to 3.0-fold greater under 1MHz than 500kHz. Rate of fluoride release was 60\% greater for the greatest initial concentration of FC in Ansul compared to the least initial concentration. While the rate of mineralization of AFFF was directly proportional to the initial concentration of Ansul, that was not the case for 3M, where the rates of mineralization were approximately the same for all three initial concentrations. Results of the study demonstrate that sonolysis is a promising technology to effectively treat AFFFs.</p>},
	issn = {1873-3336},
	doi = {10.1016/j.jhazmat.2016.05.078},
	author = {Rodriguez-Freire, Lucia and Abad-Fern{\'a}ndez, Nerea and Sierra-Alvarez, Reyes and Hoppe-Jones, Christiane and Peng, Hui and Giesy, John P and Snyder, Shane and Keswani, Manish}
}
