Nutrition and Bromatology Group, Analytical and Food Chemistry Department, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain.
J Hazard Mater. 2010 Jun 15;178(1-3):273-81. doi: 10.1016/j.jhazmat.2010.01.073. Epub 2010 Jan 18.
Polycyclic aromatic hydrocarbons (PAHs) can be formed during the refinery processes of crude petroleum. Their removal is of great importance. The same happens with other organic solvents used for the extraction of PAHs (hexane, acetonitrile...), which can be polluted with PAHs. Kinetic and equilibrium batch sorption tests were used to investigate the effect of wood ashes wastes as compared to activated carbon on the sorption of three representative PAHs from n-hexane and acetonitrile. Mussel shell ashes were discarded for batch sorption experiments because they were the only ashes containing PAHs. The equilibrium time was reached at 16 h. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the PAHs removal process. Our investigation revealed that wood ashes obtained at lower temperature (300 degrees C) did not show any PAHs sorption, while ashes obtained at higher temperature (>500 degrees C) have adsorbent sites readily available for the PAH molecules. An increase in the molecular weight of PAHs has a strong effect on sorption wood ashes wastes. As low the wood ashes particle size as high the sorption of PAHs, as a result of differences in adsorbent sites. The performance of wood ash wastes vs. activated carbon to remove 10 PAHs from organic solvents is competitive in price, and a good way for waste disposal.
多环芳烃（PAHs）可以在原油的精炼过程中形成。去除它们非常重要。其他用于提取 PAHs 的有机溶剂（己烷、乙腈等）也会受到 PAHs 的污染，情况也是如此。动力学和平衡批量吸附试验用于研究与活性炭相比，木灰废物对正己烷和乙腈中三种代表性 PAHs 的吸附效果。贻贝壳灰因含有 PAHs 而被丢弃用于批量吸附实验。平衡时间在 16 小时达到。化合物的芳香性质引起的物理吸附是控制 PAHs 去除过程的主要机制。我们的研究表明，在较低温度（300 摄氏度）下获得的木灰没有显示出任何 PAHs 吸附，而在较高温度（>500 摄氏度）下获得的木灰具有可供 PAH 分子使用的吸附位。PAHs 分子量的增加对木灰废物的吸附有很强的影响。木灰颗粒越小，对 PAHs 的吸附越强，这是由于吸附位的差异。与活性炭相比，木灰废物从有机溶剂中去除 10 种 PAHs 的性能在价格上具有竞争力，是一种废物处理的好方法。
