title: Suppression of PCDD/Fs during thermal desorption of PCBs-contaminated soil.
abstract: Thermal treatment of polychlorinated biphenyls (PCBs) contaminated soil was shown in earlier work to generate new PCBs, as well as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). In this study, this thermal desorption was conducted with addition of three distinct inhibitors, including ammonium sulphate, urea and calcium oxide, to inhibit the formation of PCDDs and PCDFs when remediating PCBs-contaminated soil. Experiments were conducted for 40 min at 400 °C after adding 1 wt.% of inhibitor. Both the total PCDD/Fs and international toxic equivalent quantity (I-TEQ) reduced when inhibitors were introduced. Of the three compounds tested, CaO shows the highest inhibition efficiency, 92.2 % for total PCDD/Fs and 95.6 % for I-TEQ. The amount of CaO added also influences the suppression efficiency of PCDD/Fs. These results suggest that promoting desorption and destruction of precursors is probably the mechanism of suppression.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Mingjiang
authors.initials: M
authors.lastname: Ni
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China. lixd@zju.edu.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Alfons
authors.initials: A
authors.lastname: Buekens
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Yan
mesh_terms: D001572:Benzofurans / Q000032:analysis; D000072338:Dibenzofurans, Polychlorinated / Q000737:chemistry*; D004787:Environmental Pollution; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006358:Hot Temperature; D011078:Polychlorinated Biphenyls / Q000737:chemistry*; D000072317:Polychlorinated Dibenzodioxins / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D000072317:Polychlorinated Dibenzodioxins; D012987:Soil; D012989:Soil Pollutants; D011078:Polychlorinated Biphenyls
keywords: CaO; I-TEQ; Inhibition; PCDD/Fs; Thermal desorption