Agronomy College, Shenyang Agricultural University, Shenyang, Liaoning, 110866, China; Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong, 528000, China.
Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong, 528000, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, Zhejiang, 311300, China.
Environ Res. 2021 Feb;193:110594. doi: 10.1016/j.envres.2020.110594. Epub 2020 Dec 8.
Potentially toxic elements (PTEs) and phthalic acid esters (PAEs) often coexist in contaminated soils. Their co-existence may affect the mutual sorption behavior, and thereby influence their bioavailability and fate in soils. To our best knowledge, the impacts of plant-and animal-derived biochar on the competitive sorption-desorption of PTEs and PAEs in soils with different organic carbon content have not been studied up to date. Therefore, in this study, batch sorption-desorption experiments were conducted to investigate the influence of biochars derived from pig carcass and Platanus orientalis branches on the mono- and competitive sorption of cadmium (Cd) and diethyl phthalate (DEP) in soils with high (HS) and low (LS) organic carbon content. The DEP sorption was well described by Freundlich isotherm model, while Cd sorption fitted better with the Langmuir isotherm model. Application of both biochars enhanced soil sorption of DEP, which increased as the application doses increased. The HS showed a stronger affinity to both DEP and Cd than the LS. In the LS, the pig carcass biochar (PB) addition was more effective to increase the sorption capacity of Cd and DEP and to reduce their desorption than woody biochar (WB) treatments. Moreover, the co-existing of Cd could reduce the sorption of DEP, especially in the LS. The presence of DEP enhanced Cd sorption in LS treated by both biochars, but the sorption of Cd was suppressed with DEP addition in the PB-amended HS. In conclusion, the soil sorption capacity of DEP and Cd was affected by biochar type, application dose and soil organic carbon content. The reciprocal effect between DEP and Cd was also a crucial factor influencing their sorption/desorption by biochar. Therefore, PB and WB, especially PB, can be used for metal/DEP immobilization due to enhanced sorption. This approach is applicable for future remediation of soils contaminated by PTEs and PAEs.
潜在有毒元素（PTEs）和邻苯二甲酸酯（PAEs）通常共存于污染土壤中。它们的共存可能会影响相互吸附行为，从而影响它们在土壤中的生物有效性和归宿。据我们所知，目前尚未研究过植物和动物源生物炭对不同有机碳含量土壤中 PTEs 和 PAEs 竞争吸附-解吸的影响。因此，本研究采用批量吸附-解吸实验，研究了猪尸和悬铃木枝生物炭对高（HS）和低（LS）有机碳含量土壤中镉（Cd）和邻苯二甲酸二乙酯（DEP）单组分及竞争吸附的影响。DEP 的吸附较好地符合 Freundlich 等温模型，而 Cd 的吸附则更符合 Langmuir 等温模型。两种生物炭的应用均增强了土壤对 DEP 的吸附，随着施用量的增加而增加。HS 对 DEP 和 Cd 的亲和力均强于 LS。在 LS 中，添加猪尸生物炭（PB）比木质生物炭（WB）处理更能有效提高 Cd 和 DEP 的吸附能力，并减少它们的解吸。此外，Cd 的共存会降低 DEP 的吸附，尤其是在 LS 中。在 LS 中，两种生物炭处理都增强了 DEP 对 Cd 的吸附，但在 PB 改良 HS 中，添加 DEP 会抑制 Cd 的吸附。综上所述，生物炭类型、施用量和土壤有机碳含量影响 DEP 和 Cd 的土壤吸附能力。DEP 和 Cd 之间的相互作用也是影响它们被生物炭吸附/解吸的关键因素。因此，PB 和 WB，特别是 PB，由于增强了吸附能力，可用于金属/DEP 固定。这种方法适用于未来修复受 PTEs 和 PAEs 污染的土壤。
