Key Laboratory of Original Agro -Environmental Pollution Prevention and Control, Ministry of Agriculture and Rural Affairs (MARA), Agro -Environmental Protection Institute, MARA, Tianjin 300191, China; Xinjiang Key Laboratory of Soil and Plant Ecological Processes, College of Grassland and Environment Sciences, Xinjiang Agricultural University, Urumqi 830052, China.
Key Laboratory of Original Agro -Environmental Pollution Prevention and Control, Ministry of Agriculture and Rural Affairs (MARA), Agro -Environmental Protection Institute, MARA, Tianjin 300191, China; Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety, Agro-Environmental Protection Institute, MARA, Tianjin 300191, China.
Environ Pollut. 2021 Feb 15;271:116308. doi: 10.1016/j.envpol.2020.116308. Epub 2020 Dec 16.
Biochar has been widely used in the mitigation of soil potentially toxic metals due to its high efficiency and low cost. Crayfish shell biochar (CSBC) was prepared at 300, 500, and 700 °C (referred to as CS300, CS500, and CS700, respectively) and the performance and mechanism of CSBC for mitigating Pb polluted water and soil was investigated. The results indicated that CSBC prepared at higher temperatures possessed higher pH value and ash content, more abundant pore structure, and higher stability. Pb adsorption onto CSBC fitted well with the pseudo second order and intraparticle diffusion models. The maximum adsorption capacity of Pb increased with the pyrolysis temperature, being 599.70, 1114.53, and 1166.44 mg·g for CS300, CS500 and CS700, respectively. Compared with the control soil samples, the content of available Pb after applying 0.05%-5% CSBC was reduced by 1.87%-16.48% in acidic soils and 1.00%-11.09% in alkaline soils. Moreover, the fractionation of exchangeable Pb was converted to stable organic matter bound, Fe-Mn oxide bound, and residue fractions. XRD, SEM-EDS, and FTIR analysis showed that ion exchange, complexation, precipitation, and C-π interaction are the dominant interaction mechanisms. Therefore, CSBC can employ as an effective immobilizing agent for the mitigation of Pb contaminated water and soil.
生物炭由于其高效和低成本而被广泛应用于土壤中潜在有毒金属的缓解。本文制备了 300、500 和 700°C（分别称为 CS300、CS500 和 CS700）的小龙虾壳生物炭，并研究了 CSBC 缓解 Pb 污染水和土壤的性能和机制。结果表明，高温下制备的 CSBC 具有更高的 pH 值和灰分含量、更丰富的孔隙结构和更高的稳定性。Pb 吸附到 CSBC 上符合准二级和内扩散模型。Pb 的最大吸附容量随热解温度的升高而增加，分别为 599.70、1114.53 和 1166.44mg·g。与对照土壤样品相比，在酸性土壤中添加 0.05%-5% CSBC 后，有效态 Pb 的含量降低了 1.87%-16.48%，在碱性土壤中降低了 1.00%-11.09%。此外，可交换态 Pb 的分馏转化为稳定的有机物质结合态、Fe-Mn 氧化物结合态和残渣态。XRD、SEM-EDS 和 FTIR 分析表明，离子交换、络合、沉淀和 C-π 相互作用是主要的相互作用机制。因此，CSBC 可以用作一种有效的固定剂，用于缓解 Pb 污染的水和土壤。
