Environmental Science, College of Engineering, China Pharmaceutical University, Nanjing 211198, China; Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
Environmental Science, College of Engineering, China Pharmaceutical University, Nanjing 211198, China.
J Environ Sci (China). 2021 Apr;102:216-225. doi: 10.1016/j.jes.2020.09.008. Epub 2020 Oct 7.
Black carbon (BC) is a promising sediment amendment, as proven by its considerable adsorption capacity for hydrophobic organic pollutants and accessibility, but its reliability when used for the removal of pollutants in natural sediments still needs to be evaluated. For example, the ageing process, resulting in changing of surface physicochemical properties of BC, will decrease the adsorption capacity and performance of BC when applied to sediment pollution control. In this study, how the ageing process and BC proportion affect the adsorption capacity of BC-sediment systems was modelled and quantitatively investigated to predict their adsorption capacity under different ageing times and BC additions. The results showed that the ageing process decreased the adsorption capacity of both BC-sediment systems, due to the blockage of the non-linear adsorption sites of BC. The adsorption capacity of rice straw black carbon (RC)-sediment systems was higher than that of fly ash black carbon (FC)-sediment systems, indicating that RC is more efficient than FC for nonylphenol (NP) pollution control in sediment. The newly established model for the prediction of adsorption capacity fits the experimental data appropriately and yields acceptable predictions, especially when based on parameters from the Freundlich model. However, to fully reflect the influence of the ageing process on BC-sediment systems and make more precise predictions, it is recommended that future work considering more factors and conditions, such as modelling of the correlation between the adsorption capacity and the pore volume or specific surface area of BC, be applied to build an accurate and sound model.
黑碳（BC）是一种很有前途的沉积物改良剂，这一点已被其对疏水性有机污染物的相当大的吸附能力和可及性所证明，但在用于去除天然沉积物中的污染物时，其可靠性仍需要评估。例如，老化过程会导致 BC 表面物理化学性质发生变化，从而降低 BC 在用于沉积物污染控制时的吸附能力和性能。在这项研究中，模拟和定量研究了老化过程和 BC 比例如何影响 BC-沉积物系统的吸附能力，以预测它们在不同老化时间和 BC 添加条件下的吸附能力。结果表明，老化过程降低了两种 BC-沉积物系统的吸附能力，这是由于 BC 的非线性吸附位点被阻塞。稻秸黑碳（RC）-沉积物系统的吸附能力高于飞灰黑碳（FC）-沉积物系统，表明 RC 比 FC 更有效地控制沉积物中的壬基酚（NP）污染。新建立的吸附能力预测模型适当地拟合了实验数据，并产生了可接受的预测结果，特别是基于 Freundlich 模型的参数。然而，为了充分反映老化过程对 BC-沉积物系统的影响并进行更精确的预测，建议未来的工作考虑更多的因素和条件，例如将吸附能力与 BC 的孔体积或比表面积之间的相关性进行建模，以建立一个准确和健全的模型。
