The Effects of Biochar Properties on Fomesafen Adsorption-Desorption Capacity of Biochar-Amended Soil
The Effects of Biochar Properties on Fomesafen Adsorption-Desorption Capacity of Biochar-Amended Soil
复制标题
生物炭性质对生物炭改良土壤氟磺胺草醚吸附-解吸能力的影响
DOI：
10.1007/s11270-017-3603-2
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发表时间：
2018-03-01
影响因子：
2.9
通讯作者：
Yu, Yunlong
中科院分区：
文献类型：
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作者：
Khorram, Mahdi Safaei;Sarmah, Ajit K.;Yu, Yunlong
热解产生的富含碳的生物质产品被认为是修复受污染土地的一种合适的选择。然而，生物炭的物理化学性质对吸附、解吸和浸出过程的影响还不完全清楚。本文研究了福美沙芬在6种生物炭改良土壤中的吸附、解吸和淋洗行为。当添加2%的阔叶木生物炭(B4)时，土壤对氟磺胺草醚的吸附系数最高(kfads=220.67)，这是因为其比表面积最高(331.70平方米/g)，而溶解有机碳(DOC)含量最低(0.43%)。相比之下，添加2%稻草生物炭(B1)的土壤吸附系数最低(kfads=116.64)，表面积最小(63.10 m~2/g)，DOC含量最高(3.67%)。然而，在解吸过程中，针叶木(B2)和核桃(B5)生物炭的土壤系数最低，其SSA高于B1，pH低于B1，这很可能是因为它们的微孔体积/总孔体积比(MPV/TPV)较低。此外，B2和B5改良剂对福美沙芬的吸附具有很强的可逆性。淋溶试验结果还表明，氟磺胺草醚从土柱中淋失的趋势与解吸的趋势一致。这些结果表明，尽管生物炭的吸附容量很可能受SSA和DOC的控制，但解吸和淋洗过程主要受MPV/TPV的影响。
Carbon-rich biomass products from thermal pyrolysis have been considered as an appropriate alternative for the remediation of contaminated lands. However, the impacts of the physico-chemical properties of biochar on adsorption, desorption, and leaching processes are not fully understood. In this study, adsorption, desorption, and leaching of fomesafen in a soil amended with six biochars were investigated. The highest fomesafen adsorption coefficient (kfads= 20.67) was observed when 2% of hardwood biochar (B4) was added onto the soil due to its highest specific surface area (SSA) (331.70 m2/g) and lowest dissolved organic carbon (DOC) content (0.43%) relative to the other tested biochars. By contrast, the lowest adsorption coefficient (kfads= 16.64) was observed in the soil amended with 2% rice straw biochar (B1) with the lowest SSA (63.10 m2/g) and highest DOC content (3.67%). Nevertheless, during desorption process, the lowest coefficients were observed in the soil amended with softwood (B2) and walnut (B5) biochars, which possessed higher SSA and lower pH than B1, most likely due to their lower micro-pore volume/total pore volume ratios (MPV/TPV). Moreover, fomesafen adsorption in the soils amended with B2 and B5 was highly reversible. The outcomes of the leaching experiment also showed that fomesafen leaching from the soil column followed the same trend as desorption. These results suggested that although the adsorption capacity of biochar is most likely controlled by SSA and DOC, desorption and leaching processes are mainly affected by MPV/TPV.