YANG Xu1,2, FU Xuewu2, HE Tianrong1, WANG Xun2, YIN Deliang1
（1. Key Laboratory of Karst Environment and Geohazard Prevention, Ministry of Education , Guizhou University, Guiyang 550003, China；
2. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550180, China）
Abstract: Chemically treated activated carbons has good adsorption performance for heavy metals like mercury. This paper worked through a series of tests and acquired an optimum proposal of collection and pre-concentration of mercury by using iodine- and chloride- impregnated activated carbon. Mercury standard samples prepared in laboratory tests show that, although iodine- and chloride- impregnated activated carbons have good adsorption performance for mercury, the collection efficiency of activated carbon traps for Hg from water is influenced by the inner diameters (ID) of traps, the mass of activated carbon and the flow rate of water. The method resulted in acceptable yields (95%) on the condition including trap ID of 0.35 cm, filled with 600 mg iodine-impregnated activated carbon, and flow rate of the peristaltic pump of 10 r/min (7 mL/min)-25 r/min (17 mL/min). Notably, increasing flow rate, the trap inner diameters and decreasing mass of activated carbon would decrease the collection efficiency of activated carbon traps from water mercury. This paper further tested the collection efficiency of iodine- impregnated activated carbon for high concentrations of mercury (the percolating water from Wanshan Mine area , concentrations ranging 37.68 to 321.57 ng/L) and low concentrations of mercury (precipitation, Guiyang City, concentrations ranging 2.76 to 9.98 ng/L). The average collection efficiencies for high concentration and low concentration of Hg reached 96.74%(n=8) and 96.09%(n=8), respectively. In this research, we proposed a new method for the pre-concentration of mercury from natural water by using chemically treated activated carbon and with water mercury isotope test.
Keywords: activated carbon; pre-concentration; adsorption efficiency; mercury isotope
EARTH AND ENVIRONMENT Vol. 43, No.4, Tot No.306, 2015, Page 469-475
