Effect of humic acid derived from leonardite on the redistribution of uranium fractions in soil

Abstract

Humic acids (HAs) are complex organic substances with abundant functional groups (e.g., carboxyl, phenolic-OH, etc.). They are commonly distributed in the soil environment and exert a double-edged sword effect in controlling the migration and transformation of uranium. However, the effects of HAs on dynamic processes associated with uranium transformation are still unclear. In this study, we used HAs derived from leonardite (L-HA) and commercial HA (C-HA) as exogenous organic matter and C-HA as the reference. UO2, UO3, and UO2(NO3)2 were used as the sources of U to explore the fractionations of uranium in the soil. We also studied the behavior of the HA. The incubation experiments were designed to investigate the effects of HA on the soil pH, uranium fraction transformation, dynamic behavior of exchangeable, weak acid, and labile uranium. The observations were made for one month. The results showed that soil pH decreased for L-HA but increased for C-HA. Under these conditions, uranium tended to transform into an inactive fraction. The dynamic behavior of exchangeable, weak acid, and labile uranium varied with the sources of HA and uranium. This study highlighted that HA could affect soil pH and the dynamic redistribution of U fractions. The results suggest that the sources of HA and U should be considered when using HA as the remediation material for uranium-contaminated soils.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 07, 2022
Source ID
10.7717/peerj.14162

Entities

People

  • Fande Meng
  • Fengxiang X. Han
  • Guodong Yuan
  • Liang Xiao
  • Qiuxiang Huang
  • Yongbing Cai

Organizations

  • Anhui Science and Technology University
  • Engineer Research and Development Center
  • Jackson State University
  • Natural Science Foundation of Anhui Province
  • Nuclear Regulatory Commission

Tags

Readers

  • Agricultural Chemistry/Soil Science
  • Aquatic Ecology
  • Educational Psychology