Bamboo Juice–Enhanced Desorption of Heavy Metals from Soil

Abstract

The performance of a novel natural agent, bamboo juice, in enhancing the desorption of heavy metals (Cd, Cu, and Pb) from contaminated soil was investigated in the present study. The bamboo juice was obtained from bamboo at elevated temperatures. The bamboo juice greatly enhanced the desorption of Cd and Cu and slightly enhanced the desorption of Pb from the soil. The maximum desorption efficiencies of Cd, Cu, and Pb reached 15.2, 25.7, and 5.9%, respectively, with the addition of 10.45% bamboo juice. The soil slurry pH dropped from 6.0 to 3.0 with the increase in bamboo juice concentration from 0 to 10.45%. The mechanism for the enhanced desorption was explained as the combined effect of pH drop and complexation. The desorbed fractions of Cd, Cu, and Pb with the addition of bamboo juice were exchangeable, followed by those bound to organic matters and Fe-Mn oxides. Although the performance of desorption enhancement by the addition of bamboo juice was lower than that of the addition of ethylenediamine tetraacetic disodium acid salt (EDTA), bamboo juice could be promising in enhancing the desorption of heavy metals from contaminated soils because of its low cost and environmental friendliness.