MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
Chemosphere. 2011 Nov;85(8):1306-11. doi: 10.1016/j.chemosphere.2011.07.042. Epub 2011 Aug 6.
Sorption of pyrene on black carbons (BCs) obtained by heating sawdust at two temperatures (400 and 700°C, denoted as 400BC and 700BC, respectively), as well as on modified BCs (via oxidation, oximation, and hydrolysis) was studied to investigate the role of BC structural characteristics in sorption of hydrophobic organic compounds. Pyrene was bound strongly by 700BC and 400BC, with organic carbon normalized distribution coefficients (K(oc)) of 10(5.04)-10(5.86) and 10(4.65)-10(5.16), respectively, at equilibrium pyrene concentrations of 10-100 μg L(-1). Both chemical composition and pore distribution of the two BCs changed after modifications, which led to changes in their sorption characteristics for pyrene. After modifications, the linearity of pyrene sorption isotherm increased for 700BC but decreased for 400BC. For 700BC, both oxidation and oximation reduced pyrene sorption, with K(oc) decreasing by 69.1-73.7% and 18.7-33.9%, respectively, whereas hydrolysis did not exert a significant influence. For 400BC, oxidation and hydrolysis reduced K(oc) by 2.28-25.9% and 29.2-33.9%, respectively, while oximation increased K(oc). In most cases, the change in sorption capacity could be explained by the changes in C content and type, polarity, surface area, and micropore volume of the BCs; however, the role of conformation (the accessibility to sorption sites) could not be ignored.
研究了在两种温度（400 和 700°C，分别表示为 400BC 和 700BC）下加热木屑得到的黑碳（BC）以及经过氧化、肟化和水解改性的 BC 对芘的吸附，以研究 BC 结构特征在吸附疏水性有机化合物中的作用。芘与 700BC 和 400BC 结合紧密，在平衡芘浓度为 10-100μg/L-1 时，有机碳归一化分配系数（Koc）分别为 10(5.04)-10(5.86)和 10(4.65)-10(5.16)。两种 BC 的化学成分和孔分布在改性后发生了变化，导致它们对芘的吸附特性发生了变化。改性后，700BC 上芘吸附等温线的线性度增加，而 400BC 上的线性度降低。对于 700BC，氧化和肟化均降低了芘的吸附，Koc 分别降低了 69.1-73.7%和 18.7-33.9%，而水解没有显著影响。对于 400BC，氧化和水解分别降低了 Koc 2.28-25.9%和 29.2-33.9%，而肟化增加了 Koc。在大多数情况下，吸附容量的变化可以用 BC 的 C 含量和类型、极性、表面积和微孔体积的变化来解释；然而，构象（吸附位点的可及性）的作用不容忽视。
