Characteristics of Modified Biochars and Their Immobilization Effect on Cu and Cd in Polluted Farmland Soil Around Smelter

被引：3

作者：

Wang X.-Y. ^{[1
,2
]}

Meng H.-B. ^{[1
,2
]}

Shen Y.-J. ^{[1
,2
]}

Wang J.-R. ^{[1
,2
]}

Zhang X. ^{[1
,2
]}

Ding J.-T. ^{[1
,2
]}

Zhou H.-B. ^{[1
,2
]}

Li C.-Y. ^{[1
,2
]}

Cheng Q.-Y. ^{[1
,2
]}

机构：

[1] Academy of Agricultural Planning and Engineering, Ministry of Agriculture and Rural Affairs, Beijing

[2] Key Laboratory of Technology and Model for Cyclic Utilization from Agricultural Resources, Ministry of Agriculture and Rural Affairs, Beijing

来源：

Huanjing Kexue/Environmental Science | 2021年 / 42卷 / 09期

关键词：

Availability; Form distribute; Heavy metals in farmland soil; Modified biochar; Structural characteristics;

D O I：

10.13227/j.hjkx.202101180

中图分类号：

学科分类号：

摘要：

Heavy metals in farmland soil are one of the most hazardous pollutants in the environment, owing to their universality and irreversibility. Modified biochar has been widely used in the adsorption and immobilization of heavy metals in soil, and its applicability is mainly determined by the types of heavy metals, pollution levels, and soil environmental conditions. Soil pollution is gradually becoming more complex and diversified, and heavy metal pollutants mostly occur in the form of compound pollution. However, most studies have focused on single heavy metal pollutant or the addition of heavy metal to soil. This study used rice straw as a raw material to prepare biochar, and modified it with K3PO4, KMnO4, and NaOH. The physicochemical and structural characteristics of the modified biochars were detected using a BET accelerated surface area and porosimetry system, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and the biochars were then analyzed for the availability and forms of Cd and Cu in soils contaminated with heavy metals in the mining area. The results showed that the surface roughness of the modified biochar increased to different degrees with increases in specific surface area and pore volume, with the NaOH modified biochar showing the most significant increases from 4.96 m2•g-1 to 60.79 m2•g-1, and from 0.02 cm3•g-1 to 0.12 cm3•g-1, respectively. The pore diameter changed in the opposite direction. The absorption peaks of the functional groups of the modified biochar were all changed, with K3PO4 modified biochar exhibiting the greatest degree of change. The addition of biochar significantly improved the soil pH value (P< 0.05), and the pH value of the soil treated with K3PO4 modified biochar exhibited the largest increase. With an application of 20.5% K3PO4 modified biochar, the availability of Cu and Cd in the soil was significantly reduced, by 75.44% and 67.70%, respectively. The immobilization efficiency of Cu was much higher than that of Cd. The best immobilization efficiency of Cu and Cd in soil was achieved with K3PO4 modified biochar. With an addition of 2% K3PO4 modified biochar, the immobilization efficiency of Cu and Cd was 61.06% and 4.12%, respectively. In summary, K3PO4 modified biochar had a better immobilization effect on both Cu and Cd in compound contaminated soil. © 2021, Science Press. All right reserved.

引用

页码：4441 / 4451

页数：10

共 59 条

[1] Ma J W, Wang F Y, Huang Z H, Et al., Simultaneous removal of 2, 4-dichlorophenol and Cd from soils by electrokinetic remediation combined with activated bamboo charcoal, Journal of Hazardous Materials, 176, 1-3, pp. 715-720, (2010)
[2] Xiao L L, Ding Y., Study on remediation of Cu and Cd in contaminated soil with the combination of biochar and maifanite, Environmental Science & Technology, 42, 2, pp. 145-150, (2019)
[3] Hamid Y, Tang L, Sohail M I, Et al., An explanation of soil amendments to reduce cadmium phytoavailability and transfer to food chain, Science of the Total Environment, 660, pp. 80-96, (2019)
[4] Lu H P, Li Z A, Gasco G, Et al., Use of magnetic biochars for the immobilization of heavy metals in a multi-contaminated soil, Science of the Total Environment, 622-623, pp. 892-899, (2018)
[5] Jing F, Chen C, Chen X M, Et al., Effects of wheat straw derived biochar on cadmium availability in a paddy soil and its accumulation in rice[J], Environmental Pollution, 257, (2020)
[6] Wang B, Gao B, Fang J E., Recent advances in engineered biochar productions and applications, Critical Reviews in Environmental Science and Technology, 47, 22, pp. 2158-2207, (2017)
[7] Liu L, Gao X H, Song G Y, Et al., Progress in the study of cadmium occurrence and transportation in soils, Energy Environmental Protection, 20, 2, pp. 6-9, (2006)
[8] Yang L, Li B, Wang C Q, Et al., Effect of modified biochars on soil cadmium stabilization in paddy soil suffered from original or exogenous contamination, Environmental Science, 37, 9, pp. 3562-3574, (2016)
[9] Sun C, Chen T, Huang Q, Et al., Enhanced adsorption for Pb(Ⅱ) and Cd(Ⅱ) of magnetic rice husk biochar by KMnO4 modification, Environmental Science and Pollution Research, 26, 9, pp. 8902-8913, (2019)
[10] Zhang J Y, Zhou H, Gu J F, Et al., Effects of nano-Fe3O4-modified biochar on iron plaque formation and Cd accumulation in rice (Oryza sativa L.)[J], Environmental Pollution, 260, (2020)

← 1 2 3 4 5 6 →