典型电子废物中多溴联苯醚的模拟浸出释放特征

选取废旧打印机外壳为典型电子废物,以商用腐殖酸溶液为浸提剂,采用浸出试验,模拟研究了废旧打印机外壳中PBDEs(多溴联苯醚)在简易填埋或与生活垃圾共处置场景下,在不同废物粒径、浸提剂DOC浓度、pH、浸提时间和液固比下的浸出特征. 分别用索氏提取法和液液萃取法提取废旧打印机外壳及其浸出液中的PBDEs,采用气相色谱-质谱法(GC-MS)对11种PBDEs同系物的浓度进行定性、定量检测. 结果表明,废旧打印机外壳中BDE28、BDE47、BDE66、BDE85、BDE99、BDE100、BDE153、BDE154被检出,而在浸出液中仅有BDE28、BDE47、BDE66、BDE85、BDE99、BDE153被检出,∑₆PBDEs的浸出率仅为0.04%~0.44%；垃圾渗滤液和土壤溶液中DOM可以促进废旧打印机外壳中PBDEs的浸出,随着浸提剂ρ(DOC)的增大,PBDEs的浸出量增加；在酸性条件下PBDEs的浸出量低于在中性条件下的浸出量；随着浸出时间的延长,PBDEs的浸出量不断增加,但在试验设定的480h内,没有得到一个液固体系的平衡时间,可见废旧打印机外壳中PBDEs的浸出是一个缓慢释放的过程. 

Simulation Study on Leaching Release Characteristics of Polybrominated Diphenyl Ethers from the Typical Electronic Waste

The waste printer outer covering was taken as a typical e-waste, and commercial humic acid was used as the extractant. Leaching tests were adopted to study the leaching characteristics of polybrominated diphenyl ethers (PBDEs) in waste printer outer parts on their different waste particle sizes, DOC concentration of extractant, pH, extraction time and liquid to solid ratio, which related with two disposal ways, simply landfill or disposed of with household waste. Soxhlet extraction and liquid-liquid extraction were applied to exact the PBDEs in the waste printer outer covering, and subsequently GC-MS was used to measure the eleven PBDEs for both qualitative and quantitative detection. The result showed that BDE28, BDE47, BDE66, BDE85, BDE99, BDE100, BDE153and BDE154were detected in the waste printer outer covering, while for leachate, only BDE28, BDE47, BDE66, BDE85, BDE99, BDE153were detected, with the leaching rates of ∑₆PBDEs from 0.04% to 0.44%. The result indicated that DOM from leachate of landfill and soil solution can enhanced the leachate of PBDEs from the waste printer outer covering. With the increasing of DOC concentrations, the leaching amounts of PBDEs increased. It further suggested that leachate of PBDEs under acid conditions were lower than that under the neutral condition, and the leaching of PBDEs gradually increased with the leaching time prolonged, however, none of a liquid-solid system equilibration time had been obtained during the 480h set in experiment. The results presented that the leachate of PBDES was a slow releasing process.