Radon exhalation from temperature treated loess

Pengfei Li; Qiang Sun; Jishi Geng; Xusheng Yan; Liyun Tang

doi:10.1016/j.scitotenv.2022.154925

Radon exhalation from temperature treated loess

Sci Total Environ. 2022 Aug 1:832:154925. doi: 10.1016/j.scitotenv.2022.154925. Epub 2022 Mar 30.

Authors

Pengfei Li¹, Qiang Sun², Jishi Geng³, Xusheng Yan⁴, Liyun Tang⁵

Affiliations

¹ College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, Shaanxi 710054, China. Electronic address: lipengfei@stu.xust.edu.cn.
² College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, Shaanxi 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, 710054, China; Key Laboratory of Coal Resources Exploration and Comprehensive Utilization, Ministry of Land and Resources, China. Electronic address: sunqiang04@cumt.edu.cn.
³ College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, Shaanxi 710054, China. Electronic address: gengjishi@cumt.edu.cn.
⁴ College of Geology and Environment, Xi'an University of Science and Technology, Xi'an, Shaanxi 710054, China. Electronic address: yxsheng187@stu.xust.edu.cn.
⁵ College of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an, Shaanxi 710054, China. Electronic address: tangly@xust.edu.cn.

PMID: 35367261
DOI: 10.1016/j.scitotenv.2022.154925

Abstract

Radon gas is a cancer risk and exists naturally in certain soils, such as loess, which is an important raw earth construction material in arid regions such as northwestern China and southern USA. Accordingly, the radon exhalationed from building materials is of increasing concern; however, there is little research on radon exhalation from loess. In this study, the pore structure and radon exhalation characteristics of heat-treated loess were investigated by nitrogen adsorption tests, swept surface electron microscopy, and radon measurements. The rate of radon exhalation increases linearly with temperature until 400 °C and then decreases exponentially. Changes in the internal pore structure (pore type, surface morphology, and specific surface area) of loess are strongly correlated with the radon exhalation rate. The volume of micropores (<2 nm diameter) is an important influence on radon exhalation ability, which is closely related to the fractal dimension of the micropore structure after heating. The results provide guidance for predicting the radiation risk posed by radon diffusing from loess.

Keywords: High temperature; Loess; Nitrogen adsorption; Pore structure; Radon exhalation; SEM.

MeSH terms

Air Pollutants, Radioactive* / analysis
Construction Materials
Exhalation
Radiation Monitoring*
Radon* / analysis
Temperature

Substances

Air Pollutants, Radioactive
Radon