Contributions of partition and adsorption to polycyclic aromatic hydrocarbons sorption by fractionated soil at different particle sizes. (August 2022)

• Record Type: Journal Article
• Authors: Tang, Lei; Gudda, Fredrick Owino; Wu, Chenxi; Ling, Wanting; El-Ramady, Hassan; Mosa, Ahmed; Wang, Jian
• Is Part Of: Chemosphere. Volume 301(2022)
• Publication Date: 2022-08
• Subjects: Phenanthrene -- Particle sizes -- Partition -- Adsorption -- Contributions; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.134715
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Partition and adsorption of polycyclic aromatic hydrocarbons (PAHs) are critical mechanisms determining their fate at the solid-liquid interface. The complexity of soil composition makes it difficult to distinguish between partition and adsorption, and bates the accuracy of the research results. This study found that the composition and structure of the soil particles (SAs) of varying particle sizes were significantly different. Partition contributed significantly to phenanthrene (Phe) sorption in SAs over 0.002 mm. However, PAHs had the highest sorption coefficient ( K d ) in SA less than 0.002 mm (SA-3), and the lower aqueous phase equilibrium concentration of Phe, the greater the adsorption effect. According to morphology and structural analysis, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), interactions of micropores, soil organic matter (SOM) and minerals enhanced the sorption of PAHs. Additionally, thermogravimetry and mass spectrometry (TG-MS) results proved that SOM could inhibit the release of PAHs adsorbed in SAs during heating process. We observed that the Log K oc of PAHs was the most important factor in determining the K d in SAs applying principal component analyses (PCA), and they have significant linear relationships ( R 2 = 0.79–0.93). These findings provide new understandings on interface reactivity of PAHs sorption to soils and the development of interface model. Graphical abstract: Image 1 Highlights: Partition was dominant in phenanthrene sorption by larger size particles. Adsorption contributed greatly to the phenanthrene sorption by smaller particles. Micropores enhanced the PAHs sorption in soil particles. The first application of TG-MS to characterize the PAHs sequestration in soil. Results provided possible insights into developing PAHs interface model.