Abstract An open experiment in environmental chemistry was introduced. In this experiment, dilute HCl, EDTA and CaCl2 were used as leaching reagents to remediate soils contaminated by heavy metals. Soil Pb and Cd contents was analyzed by inductively coupled plasma atomic emission spectroscopy before and after the leaching procedure. This experiment can help students to deepen their understanding of the knowledge of environmental chemistry including complexation/chelation, acid-base reaction, ion exchange reaction, properties of colloids, heavy metal speciation in soil, soil properties and composition. Students choose their own soil sample and the physi-chemical properties of different types of soils influence the efficiency of leaching, thus the uncertainty of the experiment can be increased. This experiment shows the frontier of the subject and is associated with real engineering practice, which encourages students to think and explore independently. Their ability of research and solving complicated problems can be enhanced.
MAO Ling-Chen, YAN Nan-Xia, LIU Li-Bo, LI Yong-Zheng. Open Experiment in Environmental Chemistry: Chemical Leaching of Heavy Metals from Contaminated Soils[J]. Chinese Journal of Chemical Education, 2020, 41(10): 71-75.
