Background:The development of the nuclear industry caused uranium contamination to the environment.As an economical and environmental friendly technique to repair uranium contaminated soils

phytoremediation has attracted much attention in recent years

and the key to this technology is uranium bioavailability in soils.Purpose:The present work investigates the impact of several inorganic anions in soils on uranium desorption from the uranium contaminated soils.Methods:Leaching test and inductively coupled plasma-mass spectrometry(ICP-MS) was used in this study.Results:It was found that uranium desorption rate increased with CO32 concentration

and the equilibrium was obtained with resolution rate of 85% 90%.Uranium desorption rate could increase from 41% 53%when SO42 content was in the range of 5 40 g·L 1.While Cl had no effect on uranium desorption.Uranium desorption obtained equilibrium at a volume of 20 mL for strippant with 5-g uranium contaminated soil.In the former3 days

uranium desorption rate increased rapidly

and finally obtained equilibrium at 105-h with a desorption rate of90%.Conclusions:First

CO32 and SO42 have better effect on uranium desorption compared to other anions.Effect of CO32 was greater than SO42 due to a greater binding ability of CO32 to U(VI)

while Cl had little effect.Second

the solvent volume and leaching time also impact uranium leaching yield.This study would be helpful to increase the knowledge of improving uranium bioavailability in the soil

which also laid a theoretical foundation to improve the efficiency of phytoremediation.