Science and Engineering Faculty, Queensland University of Technology, G.P.O. Box 2434, Brisbane, QLD 4001, Australia.
Environ Pollut. 2014 Jan;184:44-53. doi: 10.1016/j.envpol.2013.08.010. Epub 2013 Sep 7.
Despite common knowledge that the metal content adsorbed by fine particles is relatively higher compared to coarser particles, the reasons for this phenomenon have gained little research attention. The research study discussed in the paper investigated the variations in metal content for different particle sizes of solids associated with pollutant build-up on urban road surfaces. Data analysis confirmed that parameters favourable for metal adsorption to solids such as specific surface area, organic carbon content, effective cation exchange capacity and clay forming minerals content decrease with the increase in particle size. Furthermore, the mineralogical composition of solids was found to be the governing factor influencing the specific surface area and effective cation exchange capacity. There is high quartz content in particles >150 μm compared to particles <150 μm. As particle size reduces below 150 μm, the clay forming minerals content increases, providing favourable physical and chemical properties that influence adsorption.
尽管人们普遍认为细颗粒吸附的金属含量相对较高，而粗颗粒的金属含量则较低，但这一现象的原因却很少受到关注。本文研究了城市路面污染物积累过程中不同固体颗粒大小的金属含量变化。数据分析证实，有利于金属吸附到固体上的参数，如比表面积、有机碳含量、有效阳离子交换容量和粘土形成矿物含量，随着颗粒尺寸的增大而减小。此外，还发现固体的矿物组成是影响比表面积和有效阳离子交换容量的控制因素。>150μm 的颗粒中石英含量高于<150μm 的颗粒。当颗粒尺寸减小到<150μm 以下时，粘土形成矿物的含量增加，提供了有利于吸附的物理和化学性质。
