Effects of mineral species and petroleum components on thermal desorption behavior of petroleum-contaminated soil

Zhiying Xiao; Shuhai Guo; Fenglian Cheng; Sa Wang

doi:10.1016/j.chemosphere.2022.135548

Effects of mineral species and petroleum components on thermal desorption behavior of petroleum-contaminated soil

Chemosphere. 2022 Nov;307(Pt 1):135548. doi: 10.1016/j.chemosphere.2022.135548. Epub 2022 Jul 5.

Authors

Zhiying Xiao¹, Shuhai Guo², Fenglian Cheng³, Sa Wang⁴

Affiliations

¹ Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China; College of Chemistry and Materials Science, Inner Mongolia University for Nationalities, Tongliao, 028000, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: xiaozhiying19@mails.ucas.ac.cn.
² Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China. Electronic address: shuhaiguo@iae.ac.cn.
³ Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China. Electronic address: chengfl@iae.ac.cn.
⁴ Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China. Electronic address: ws2600043@163.com.

PMID: 35803372
DOI: 10.1016/j.chemosphere.2022.135548

Abstract

Thermal desorption (TD) behavior of high-concentration petroleum-contaminated soil (PCS) is affected by soil composition, especially inorganic minerals. In this study, the TD behavior of petroleum-contaminated quartz (original mineral) and kaoline (clay mineral) were compared with those of pure petroleum (Petro-free); their "saturate, aromatic, resin, and asphaltenes" (SARA) fractions were investigated using thermogravimetry and differential thermogravimetry (TG-DTG). The modelling of the petroleum removal kinetics was also analyzed to provide insights into the mechanism. The results revealed that the limiting factor controlling the desorption of petroleum from quartz (Petro-Qtz) and kaoline (Petro-Kln) is the minerals, which increased the effective TD temperature by 200 °C and decreased TD efficiency by 2%. Compared to Petro-Qtz, Petro-Kln showed a lower desorption efficiency of 5% and the process was accomplished at a higher temperature of 100 °C. The investigation on SARA fractions indicated that polar fractions (i.e., aromatics, resins, and asphaltenes) were strongly captured by the minerals. The increment of the TD temperature of petroleum (resins-160 °C > aromatics-20 °C > saturates-5 °C) increased with the polarity of petroleum components. These results could be validated by thermogravimetry-gas chromatography/mass spectroscopy (TG-GC/MS) through the delayed desorption of naphthalene and acenaphthene. Furthermore, the increment of the TD temperature of SARA fractions on kaoline was higher than those on quartz. This makes sense because the kaoline decreased the diffusion of hydrocarbons due to its porosity features and higher specific surface area (kaoline 5.3300 m² g^-1, quartz 0.1153 m² g^-1). In addition, the analysis of the desorption kinetic models showed that the observed hysteresis was related to the diffusion barrier caused by chemisorption (n＜1). In consequence, the Petro-Kln showed a lower desorption efficiency, a slower desorption, and as a result, a higher energy consumption (0.476 kW h) for thermal remediation than Petro-Qtz (0.238 kW h).

Keywords: Characteristic microstructure; Energy consumption; Kaoline; Quartz; Thermal desorption.

MeSH terms

Acenaphthenes
Clay
Hydrocarbons / chemistry
Minerals / chemistry
Petroleum* / analysis
Quartz
Soil / chemistry
Soil Pollutants* / analysis

Substances

Acenaphthenes
Hydrocarbons
Minerals
Petroleum
Soil
Soil Pollutants
Quartz
Clay