Open AccessEffect of amendments (lime–zeolite–biochar) on the immobilization of Cd and Pb in a contaminated acidic soil
Author(s) -
Di Zhang,
Ting Li,
Xiaohu Wu,
Yuting Wang
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/742/1/012016
Subject(s) - biochar , lime , amendment , zeolite , environmental remediation , chemistry , environmental chemistry , soil ph , bioavailability , cadmium , soil contamination , soil conditioner , contamination , soil water , environmental science , soil science , metallurgy , materials science , catalysis , organic chemistry , ecology , pyrolysis , biology , bioinformatics , political science , law
An incubation experiment was carried out to study the remediation effect of lime, zeolite and biochar under different ratios on cadmium (Cd) and lead (Pb) contaminated soil. Soil pH, organic carbon (SOC), bioavailability and mobility of Cd and Pb were investigated. The results indicated that combined application of lime, zeolite and biochar can significantly increase soil pH, the increment was from 0.15 to 0.76. Compared to the control treatment, the concentrations of CaCl 2 -, TCLP-Cd and Pb significantly decreased in all amended treatments. Considering the soil environmental quality and immobilization efficiency, the ratio of lime, zeolite and biochar was determined to be 1:2:2. The application rate of combined amendment (lime:zeolite:biochar=1:2:2) had obvious effect on soil pH, SOC and removal efficiency of Cd and Pb, promoting the acid soluble fractions of Cd and Pb to residual fractions, especially in higher application rate (5.0% and 10.0%). However, there was no significant difference when the application rate exceeded 5.0%. Therefore, it was suggested that the application rate of combined amendment (lime:zeolite:biochar=1:2:2) could be 5.0% in short-term soil remediation.