Effect of sorbate planarity on environmental black carbon sorption.
Effect of sorbate planarity on environmental black carbon sorption.
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DOI：
10.1021/es049862g
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发表时间：
2004-07
影响因子：
11.4
通讯作者：
G. Cornelissen;Marie Elmquist;I. Groth;O. Gustafsson
中科院分区：
文献类型：
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作者：
G. Cornelissen;Marie Elmquist;I. Groth;O. Gustafsson
烟灰和木炭统称为“黑碳”或BC，可以对许多疏水性有机化合物表现出极强的吸附作用。为了将BC吸附纳入命运模型，了解BC纳米孔表面积非常重要。此外，了解 BC 吸附对于哪些化合物可能很重要也是有用的。通过在超低压下对通过 HF 处理和/或 375 摄氏度的化学热氧化而大量富集 BC 的沉积物进行氮吸附测量，我们发现环境 BC 在 PHE 中具有纳米孔隙度，约为 4-PCB >> 2,2'-PCB，跨度为 50-200，具体取决于浓度。非平面 2,2'-PCB 显示出比平面化合物 (nF = 0.54-0.70) 更高的线性 BC 吸附 (nF = 0.92)。这表明空间位阻强烈减弱了非平面 PCB 的 BC-山梨酸盐相互作用。因此，BC 对于平面化合物的环境吸附（> 50% 在纳克/升范围内被 BC 吸附）比非平面化合物 (<10-20%) 更重要。使用测量的BC纳米孔表面积，可以发现建模和测量的BC吸附数据之间非常一致。
Soot and charcoal, collectively termed "black carbon" or BC, can exhibit extremely strong sorption of many hydrophobic organic compounds. In order to include BC sorption in fate models, it is important to know BC nanopore surface areas. In addition, it is useful to know for which compounds BC sorption can be expected to be important. By nitrogen adsorption measurements at ultralow pressures on sediment that was strongly enriched in BC by HF treatment and/or chemothermal oxidation at 375 degrees C, we found that environmental BC has nanoporosity in the PHE approximately 4-PCB >> 2,2'-PCB and spanned a factor of 50-200, depending on concentration. Nonplanar 2,2'-PCB showed much more linear BC sorption (nF = 0.92) than the planar compounds (nF = 0.54-0.70). This shows that steric hindrance strongly attenuates BC-sorbate interactions for a nonplanar PCB. Thus, BC is more important for environmental sorption of planar compounds (>50% sorbed to BC in the nanogram per liter range) than for nonplanar ones (<10-20%). Using the measured BC nanopore surface area, a close agreement between modeled and measured BC sorption data could be found.