Affiliations: Institute of Applied Ecology, Chinese Academy of
Sciences, Shenyang 110016, China | Graduate School of the Chinese Academy of Sciences,
Beijing 100039, China | Shenyang Agriculture University, Shenyang 110161,
China
Abstract: This study reports the feasibility of remediation of a heavy metal
(HM) contaminated soil using tartaric acid, an environmentally-friendly
extractant. Batch experiments were performed to test the factors influencing
remediation of the HM contaminated soil. An empirical model was employed to
describe the kinetics of HM dissolution/desorption and to predict equilibrium
concentrations of HMs in soil leachate. The changes of HMs in different
fractions before and after tartaric acid treatment were also investigated.
Tartaric acid solution containing HMs was regenerated by chestnut shells.
Results show that utilization of tartaric acid was effective for removal of HMs
from the contaminated soil, attaining 50%–60% of Cd, 40%–50% of Pb,
40%–50% of Cu and 20%–30% of Zn in the pH range of 3.5–4.0
within 24 h. Mass transfer coefficients for cadmium (Cd) and lead (Pb) were
much higher than those for copper (Cu) and zinc (Zn). Sequential fractionations
of treated and untreated soil samples showed that tartaric acid was effective
in removing the exchangeable, carbonate fractions of Cd, Zn and Cu from the
contaminated soil. The contents of Pb and Cu in Fe-Mn oxide fraciton were also
significantly decreased by tartaric acid treatment. One hundred milliliters of
tartaric acid solution containing HMs could be regenerated by 10 g chestnut
shells in a batch reactor. Such a remediation procedure indicated that tartaric
acid is a promising agent for remediation of HM contaminated soils. However,
further research is needed before the method can be practically used for in
situ remediation of contaminated sites
Keywords: tartaric acid, soil remediation, heavy metals, soil contamination
