TY - JOUR
T1 - A SEM and X-ray study for investigation of solidified/stabilized arsenic-iron hydroxide sludge
AU - Phenrat, Tanapon
AU - Marhaba, Taha F.
AU - Rachakornkij, Manaskorn
N1 - Funding Information:
This research work was funded by the National Research Center for Environmental and Hazardous Waste Management, Chulalongkorn University, Bangkok, Thailand and the New Jersey Applied Water Research Center, New Jersey Institute of Technology, Newark, NJ, USA. The authors also would like to express gratitude to the Scientific and Technological Research Equipment Center of Chulalongkorn University, especially Mr. Boonlur who gave many helpful suggestions. The assistance of Dr. Khemarath Osathaphan is also gratefully acknowledged.
PY - 2005/2/14
Y1 - 2005/2/14
N2 - Despite the fact that the solidification/stabilization of arsenic containing wastes with Portland cement and lime has an extensively documented history of use, the physical and chemical phenomena as a result of the interaction between arsenic and cement components have not been fully characterized. The study investigates the behavior of synthesized arsenic-iron hydroxide sludge, the by-product of arsenic removal by coagulation with ferric chloride, in solidified/stabilized matrices as well as its binding mechanisms by exploring the cementitious matrices in the micro-scale by scanning electron microscopy equipped with energy dispersive X-ray spectrometer (SEM-EDS). It was revealed that arsenic can be chemically fixed into cementitious environment of the solidified/stabilized matrices by three important immobilization mechanisms; sorption onto CSH surface, replacing SO42- of ettringite, and reaction with cement components to form calcium-arsenic compounds, the solubility limiting phases.
AB - Despite the fact that the solidification/stabilization of arsenic containing wastes with Portland cement and lime has an extensively documented history of use, the physical and chemical phenomena as a result of the interaction between arsenic and cement components have not been fully characterized. The study investigates the behavior of synthesized arsenic-iron hydroxide sludge, the by-product of arsenic removal by coagulation with ferric chloride, in solidified/stabilized matrices as well as its binding mechanisms by exploring the cementitious matrices in the micro-scale by scanning electron microscopy equipped with energy dispersive X-ray spectrometer (SEM-EDS). It was revealed that arsenic can be chemically fixed into cementitious environment of the solidified/stabilized matrices by three important immobilization mechanisms; sorption onto CSH surface, replacing SO42- of ettringite, and reaction with cement components to form calcium-arsenic compounds, the solubility limiting phases.
KW - Arsenic-iron hydroxide sludge
KW - Immobilization mechanism
KW - Microstructure
KW - SEM-EDS
KW - Solidification/stabilization
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U2 - 10.1016/j.jhazmat.2004.10.019
DO - 10.1016/j.jhazmat.2004.10.019
M3 - Article
C2 - 15721543
AN - SCOPUS:13844307307
SN - 0304-3894
VL - 118
SP - 185
EP - 195
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
IS - 1-3
ER -