Immobilization of Pb and Cu in polluted soil by superphosphate, multi-walled carbon nanotube, rice straw and its derived biochar.
Lead (Pb) and copper (Cu) contamination in croplands pose severe health hazards and environmental concerns throughout soil-food chain transfer. In the present study, BCR, TCLP, CaCl2, and SBET techniques were employed to evaluate the simultaneous effectiveness of rice straw (RS) and its derived biochar (BC), multiwall carbon nanotube (MWCNT), and single superphosphate (SSP) to immobilize the Pb and Cu in co-contaminated soil. The BCR sequential extraction results suggested that with increasing BC and SSP amount, the acid-soluble fractions decreased while oxidizable and residual proportions of Pb and Cu were increased significantly. Compared to SSP, the application of BC amendment substantially modified partitioning of Cu from easily exchangeable phase to less bioavailable residual bound fraction. The immobilized Pb and Cu were mainly transformed to reducible forms. The TCLP and CaCl2-extracted Pb and Cu were reduced significantly by the addition of BC compared to RS and MWCNT, whereas the bio-accessibility of Pb significantly reduced with RS addition. SSP showed better results for Pb immobilization while marginal for Cu in co-contaminated soil. Overall, the addition of BC offered the best results and could be effective in both Pb and Cu immobilization thereby reducing their mobility and bioavailability in the co-contaminated soil.
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Muhammad Shahid
MS
Rizwan
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Muhammad
M
Imtiaz
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Guoyong
G
Huang
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Muhammad Afzal
MA
Chhajro
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Yonghong
Y
Liu
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Qingling
Q
Fu
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Jun
J
Zhu
University College of Agriculture, University of Sargodha, University road, Sargodha, Punjab, 40100, Pakistan.
Muhammad
M
Ashraf
Soil & Water Chemistry Lab. Department of Soil Science, Federal University of Santa Maria, 91105-900, Rio Grande do Sul, Brazil.
Mohsin
M
Zafar
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China.
Saqib
S
Bashir
Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei, 430070, P. R. China. hqhu@mail.hzau.edu.cn.
Hongqing
H
Hu
D001682:Biological Availability; D002606:Charcoal / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D011756:Diphosphates / Q000737:chemistry*; D004787:Environmental Pollution; D052918:Environmental Restoration and Remediation / Q000295:instrumentation / Q000379:methods*; D007854:Lead / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012275:Oryza / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000737:chemistry*
D011756:Diphosphates; D037742:Nanotubes, Carbon; D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal; D007854:Lead; D003300:Copper; C033414:superphosphate
Bio-accessibility; Biochar; Heavy metals; Immobilization; Multiwall carbon nanotube; Superphosphate