Speciation of heavy metals in sludge from electroplating industry / Noorhazlina Binti Abu Bakar
Application of sequential extraction method to environmental samples provides relevant information about possible toxicity, mobility, and bioavailability of heavy metals when they are discharged into the environment. The concentration of heavy metals in three electroplating sludge samples (two sa...
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| Format: | Thesis |
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2013
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| Online Access: | http://studentsrepo.um.edu.my/6419/ http://studentsrepo.um.edu.my/6419/1/ABSTRACT.pdf http://studentsrepo.um.edu.my/6419/2/APPENDIX_A%2DC.pdf http://studentsrepo.um.edu.my/6419/3/APPENDIX_D.pdf http://studentsrepo.um.edu.my/6419/4/CHAPTER.pdf http://studentsrepo.um.edu.my/6419/5/PREFACE_HASIL_KERJA.pdf http://studentsrepo.um.edu.my/6419/6/TABLE_OF_CONTENTS.pdf |
| Summary: | Application of sequential extraction method to environmental samples provides relevant
information about possible toxicity, mobility, and bioavailability of heavy metals when
they are discharged into the environment. The concentration of heavy metals in three
electroplating sludge samples (two samples from Zn electroplating industries and one
sample from Ni electroplating industry) and potential of mobility based on its association
form were studied. BCR sequential extraction method was used to fractionate the metal
content into acid soluble/exchangeable, reducible and oxidizable fractions. Residual and
total metal content were determined in aqua regia digest. The extract were analysed for
metals using inductively coupled plasma mass spectrometry (ICP-MS). Zn concentration
was found to be the highest in the samples collected from zinc electroplating industries
(145.9 and 187.7 g kg-1) as compared to that of nickel electroplating industry (0.6 g kg-1).
The descending order of the average total metal contents for these three samples were
Zn>Ni>Fe>Cr>Pb>Cd. From the sequential extraction, Cd, Zn and Ni were found more
frequently in acid soluble/exchangeable fraction, showed its susceptibility to be leached
easily. The oxidizable form is dominant for all the three samples studied. Also, Fe and Pb
extracted were higher in residual fraction. Due to the higher total Zn and Ni concentrations
and its high mobility, the investigated sludges should be disposed off into landfill after
stabilization to prevent the leaching of metals to the surrounding area. |
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