[Speciation distribution characters of heavy metals in waste printed circuit boards].
The environmental availability of heavy metals from the waste printed circuit boards (PCBs) were studied through BCR's three-stage extraction procedures from EU and Tessier's five sequential extraction procedures. The results show that the heavy metal extraction rates with BCR's procedures are higher than that with Tessier's from waste PCBs. There are significant differences in fraction distributions of heavy metals in PCBs. The speciation of Ni in the PCBs exists mainly in residual forms and has little effect on the environment. The percentage of acidic extractable forms with BCR's method and the total amount of exchangeable and carbonate which bound for Tessier's procedure of Pb and Zn are high, in the South China, the two metals are more easily released by acid rain. Acidic extractable forms of Cu is the main speciation in PCBs with BCR's extraction procedures, while the percentage of Fe-Mn oxides- bound of Cu is the highest with Tessier's procedures, though the result is not agree consistent, due to the high content of Cu in PCBs, the harm of Cu from PCBs could not be neglected.
Zhao
Guo-hua
GH
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China. njughzhao@yahoo.com.cn
Luo
Xing-zhang
XZ
Huang
Zhuo-hui
ZH
Feng
Jing-wei
JW
Zheng
Zheng
Z
Gao
Shun-zhi
SZ
Nie
Er
E
Ni
Li-xiao
LX
D002681:China; D055615:Electrical Equipment and Supplies; D004581:Electronics; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D015386:Hazardous Substances / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis*; D012037:Refuse Disposal
D004785:Environmental Pollutants; D015386:Hazardous Substances; D019216:Metals, Heavy