TY - JOUR
T1 - Leaching of Arsenic from coal fly ashes 2. Arsenic Pre-leaching with sodium gluconate solution
AU - Xu, Yan‐Hua
AU - Nakajima, Tsunenori
AU - Ohki, Akira
PY - 2001/5
Y1 - 2001/5
N2 - The present study deals with the development of an efficient and reliable process for safe disposal of coal fly ash to remove arsenic that has been found to be the most easily leachable and hazardous heavy metal in coal fly ash. Pre-leaching of fly ash prior to disposal by a natural chelating agent, sodium gluconate (SG), was proposed and studied. Several operational factors influencing arsenic leachability, such as concentration of SG solution, liquid to solid ratio, pH, length of leaching time and leaching temperature were examined. Arsenic was found to leach out substantially with SG, but almost no further release was observed from the ash pre-leached by SG. After the pre-leaching treatment, the desirable high buffering capacity of the ash was well sustained. SG solution was effectively regenerated by activated alumina adsorption so that it could be successfully reused for multiple leaching/adsorption cycles.
AB - The present study deals with the development of an efficient and reliable process for safe disposal of coal fly ash to remove arsenic that has been found to be the most easily leachable and hazardous heavy metal in coal fly ash. Pre-leaching of fly ash prior to disposal by a natural chelating agent, sodium gluconate (SG), was proposed and studied. Several operational factors influencing arsenic leachability, such as concentration of SG solution, liquid to solid ratio, pH, length of leaching time and leaching temperature were examined. Arsenic was found to leach out substantially with SG, but almost no further release was observed from the ash pre-leached by SG. After the pre-leaching treatment, the desirable high buffering capacity of the ash was well sustained. SG solution was effectively regenerated by activated alumina adsorption so that it could be successfully reused for multiple leaching/adsorption cycles.
KW - Arsenic
KW - Chelating agent
KW - Coal fly ash
KW - Leaching
KW - Sodium gluconate solution
UR - http://www.scopus.com/inward/record.url?scp=0035701251&partnerID=8YFLogxK
U2 - 10.1080/02772240109359020
DO - 10.1080/02772240109359020
M3 - 文章
AN - SCOPUS:0035701251
SN - 0277-2248
VL - 81
SP - 69
EP - 80
JO - Toxicological and Environmental Chemistry
JF - Toxicological and Environmental Chemistry
IS - 1-2
ER -